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Unmanned Spaceflight.com _ LRO & LCROSS _ LCROSS Lunar Impact

Posted by: nprev Oct 9 2009, 02:19 AM

T minus 9 hrs. 10 min till impact. NASA TV coverage begins @ 1015 GMT (0315 PDT). Link to coverage http://www.nasa.gov/mission_pages/LCROSS/main/index.html.

Posted by: Astro0 Oct 9 2009, 03:06 AM

Separation image (inset) and interpretation (using Celestia add-on).


Posted by: Hungry4info Oct 9 2009, 03:11 AM

You've had much better luck with simulating it in Celestia with that add-on than I. In Celestia, I had the moon behind the Centaur as seen from LCROSS, and there doesn't seem to be the moon in the live feed.

Posted by: Shaka Oct 9 2009, 03:19 AM

smile.gif O.K. Bend over please.
This may sting a little.

Posted by: nprev Oct 9 2009, 04:15 AM

(Ouch!!!!!!) tongue.gif

Astro0, what's the FOV of that Celestia view? Reason I ask is that the Moon wasn't visible in the post-separation raw images as far as I could see; just curious. (Great composition, BTW, as per your usual!)

(EDIT: I see that Hungry already mentioned that.)

Posted by: Stu Oct 9 2009, 05:51 AM

Humph.

Stupid Moon.

Have to go to work, so I'll miss the whole thing.

(scuffs toes on ground)

Not fair.

mad.gif


Have fun everyone! Looking forward to hearing all about it when I get back.

Posted by: Astro0 Oct 9 2009, 06:26 AM

nprev... I've got no idea of the FOV for that image...I just thought it looked nice and helped orient me to the 'real' image...not even sure if it's right! Remember me cool.gif I'm the 'artist' not the scientist laugh.gif

Posted by: Hungry4info Oct 9 2009, 07:12 AM

QUOTE (nprev @ Oct 8 2009, 11:15 PM) *
...Reason I ask is that the Moon wasn't visible in the post-separation raw images as far as I could see; just curious.


Is this the terminator of the moon in the lower-left corner of the IR image? If so, it may suggest either a very narrow FOV, or simply that the moon is quite off-centre from the image.

http://www.nasa.gov/externalflash/lcross-centaur-separation/centaur-separation2.jpg

Posted by: ustrax Oct 9 2009, 07:16 AM

http://www.facebook.com/photo.php?pid=698608&l=95856614f8&id=1311707986, ignorant mode here, where's the impact site in this photo? tongue.gif

Posted by: Hungry4info Oct 9 2009, 07:22 AM

Haha, it's the very southern point in that image. I don't suspect your image is detailed enough to resolve Cabeus crater.

Posted by: ElkGroveDan Oct 9 2009, 07:25 AM

QUOTE (ustrax @ Oct 9 2009, 12:16 AM) *
http://www.facebook.com/photo.php?pid=698608&l=95856614f8&id=1311707986, ignorant mode here, where's the impact site in this photo? tongue.gif


It's at the left tip of the lighted side in that image Rui/

Posted by: ustrax Oct 9 2009, 08:43 AM

Thanks guys! smile.gif

Posted by: Decepticon Oct 9 2009, 08:53 AM

Tee Hee laugh.gif


 

Posted by: Decepticon Oct 9 2009, 09:34 AM

Every time I see the impact story on the news, the media tends to over play the impact.

Posted by: Zvezdichko Oct 9 2009, 09:38 AM

I can already see that. Bombing the Moon, that's it. Fortunately or not, we're living in a sci-fi shaped world. And there are people who are afraid of the impact. But there's no danger. Impacts occur very often.

Posted by: MahFL Oct 9 2009, 10:04 AM

Good morning all.

Posted by: Zvezdichko Oct 9 2009, 10:14 AM

Broadcast starts in a minute:

http://www.nasa.gov/multimedia/nasatv/index.html

Posted by: MahFL Oct 9 2009, 10:22 AM

Can't watch video at work sad.gif. I'll make do with JSC stills.

Posted by: Zvezdichko Oct 9 2009, 10:25 AM

I usually take snapshots, but I'm also at work and don't have the graphics programs. I'll try however to do the best I can from here.

Posted by: Phil Stooke Oct 9 2009, 10:26 AM

Recent Twitter post:

SSC_Final_ME_sph = 310.52235358536 E -84.7311739853509
about 1 hour ago from web
LCROSS Centaur and SSC target coordinates (Lat., Lon. in ME): Centaur_Final_ME_sph = 311.302088477883 E -84.6743872273512
about 1 hour ago from web

I see they are targeting an individual molecule...

Phil

Posted by: volcanopele Oct 9 2009, 10:30 AM

If that's a water molecule is that such a bad thing?

Posted by: Hungry4info Oct 9 2009, 10:37 AM

The target molecule will probably be destroyed. Perhaps they're hoping to detect the water molecules adjacent to that one? tongue.gif

Posted by: Zvezdichko Oct 9 2009, 10:45 AM

Moon!

Don't know if it was the Moon imaged by the previous flyby or a live downlink. Too noisy here.

 

Posted by: Zvezdichko Oct 9 2009, 10:48 AM

All instruments are operating nominally, that's great news, great chance of getting data!

Posted by: AndyG Oct 9 2009, 10:49 AM

Live - and getting bigger! smile.gif

Posted by: centsworth_II Oct 9 2009, 10:50 AM

QUOTE (Zvezdichko @ Oct 9 2009, 05:45 AM) *
Don't know if it was the Moon imaged by the previous flyby or a live downlink. Too noisy here.

Sounded live to me. the scientist being interviewed was quite emotional when asked his feeling at the time it was shown. He said he was feeling [many] emotions at the same time.

Posted by: deefatman Oct 9 2009, 10:50 AM

I didn't realise Hubble was going to be observing things!

Posted by: Zvezdichko Oct 9 2009, 10:54 AM

Yes, this is the Moon seen by LCROSS in real time!

Yet another screenshot coming. Unfortunately I won't be able to combine them all - no graphics programs here.

http://img132.imageshack.us/i/lcross3.jpg/

Posted by: volcanopele Oct 9 2009, 11:00 AM

Which crater is Cabeus in that screenshot?

Posted by: Zvezdichko Oct 9 2009, 11:00 AM

http://img12.imageshack.us/i/lcross5.jpg/


Posted by: centsworth_II Oct 9 2009, 11:09 AM

QUOTE (volcanopele @ Oct 9 2009, 06:00 AM) *
Which crater is Cabeus in that screenshot?

Asked if they can pick out the target, the scientists said it's still too far away for them to pick it out.

Posted by: deefatman Oct 9 2009, 11:10 AM

It really reminds you how big the moon is when you consider how long left there is and that the moon is already filling up the entire frame, we always consider the moon small next to earth but in it's own right it's still enormous.

Posted by: elakdawalla Oct 9 2009, 11:11 AM

Can anybody spot Cabeus in the LCROSS view? Having trouble getting oriented this morning, even with coffee rolleyes.gif

Posted by: Zvezdichko Oct 9 2009, 11:12 AM

Live view from the IR camera!


 

Posted by: ElkGroveDan Oct 9 2009, 11:13 AM

YAWN .... I am tired! Going to watch on the large screen TV. I'll check back here in a while.

Posted by: volcanopele Oct 9 2009, 11:15 AM

Okay, nevermind, here is what I could put together:


Posted by: volcanopele Oct 9 2009, 11:16 AM

In the current view on screen now, Cabeus is just below and to the left of center

Posted by: nprev Oct 9 2009, 11:17 AM

'Mornin' everyone. Just got the NASA feed working on my computer; @#$% cable company here STILL don't carry NASA TV.

(The marine layer has torpedoed plans to set up my scope!)

Posted by: MahFL Oct 9 2009, 11:18 AM

try this link !

http://www.mmto.org/lcross/


Posted by: Juramike Oct 9 2009, 11:18 AM

(Are we supposed to eat peanuts now?)

Posted by: Zvezdichko Oct 9 2009, 11:19 AM

Visible...

http://img19.imageshack.us/i/lcross9.jpg/

And IR image...

http://img38.imageshack.us/i/lcross10.jpg/

Posted by: volcanopele Oct 9 2009, 11:22 AM

QUOTE (nprev @ Oct 9 2009, 04:17 AM) *
'Mornin' everyone. Just got the NASA feed working on my computer; @#$% cable company here STILL don't carry NASA TV.

(The marine layer has torpedoed plans to set up my scope!)

Be careful. Even if NASA TV doesn't show up on your digital cable box lineup, NASA TV may still be available over clearQAM by plugging the coax directly into your TV. That's the case here in Tucson with Cox Cable. In Tucson, it's on channel 72-4.

Posted by: mchan Oct 9 2009, 11:27 AM

Bit humorous there when they went thru the station checks and concluded with "go for impact". It's not like they can scrub...

Posted by: deglr6328 Oct 9 2009, 11:29 AM

(Are we supposed to eat peanuts now?)


NO! Eating peanuts during a crash (even when deliberate) confuses the flying spaghetti monster and then he won't be able to be relied upon to guide our future soft landing missions down safely with his noodly appendage.

Posted by: Juramike Oct 9 2009, 11:29 AM

The image is growing visibly frame by frame. This is so cool....

Posted by: volcanopele Oct 9 2009, 11:29 AM

Thanks for the link, MahFL! Slooh was rained and clouded out at both locations.

Cloudy here...

Posted by: Zvezdichko Oct 9 2009, 11:29 AM

http://img405.imageshack.us/i/lcross14.jpg/

Latest snapshot

Posted by: AndyG Oct 9 2009, 11:31 AM

And poor Stu is missing it!

Posted by: volcanopele Oct 9 2009, 11:32 AM

Impact flash! Woot!

EDIT: err. maybe not... that's just a surface feature...

Posted by: deglr6328 Oct 9 2009, 11:39 AM

ehhhhhh, did I miss it? I didn't see a thing on the video.

Posted by: Zvezdichko Oct 9 2009, 11:40 AM

http://img39.imageshack.us/i/lcross21.jpg/


This is probably the thermal confirmation, I think

Posted by: deefatman Oct 9 2009, 11:40 AM

I didn't see anything either

Posted by: nprev Oct 9 2009, 11:40 AM

I didn't see anything...
but the R/T lithobraking was cool!

Dim flash suggests soil impact rather than rocks...good news!

Posted by: Hungry4info Oct 9 2009, 11:41 AM

I never saw an impact flash (at least one that I recognized as such).
Is what we saw the best quality LCROSS images?

Posted by: MahFL Oct 9 2009, 11:42 AM

I saw NOTHING !!!!, thats my story and I am sticking to it.

Posted by: nprev Oct 9 2009, 11:42 AM

NASA TV showing the IR now. There's a hotspot, all right.

Posted by: ElkGroveDan Oct 9 2009, 11:44 AM

I'm going back to bed. You kids woke me up for this?

Posted by: Zvezdichko Oct 9 2009, 11:44 AM

http://img96.imageshack.us/i/lcross23.jpg/

Is this the hot spot anyway?

Posted by: deglr6328 Oct 9 2009, 11:46 AM

I think that's just a sunlit crater rim nprev. Zvez, that mid-IR image is just mostly noise from excessively high gain after the last sunlit hotspots went out of frame.

Posted by: centsworth_II Oct 9 2009, 11:46 AM

QUOTE (Zvezdichko @ Oct 9 2009, 06:44 AM) *
Is this the hot spot anyway?

Looks like the hot, sunlit peak of a crater rim.

Posted by: tanjent Oct 9 2009, 11:47 AM

One of the commentators identified that hotspot as sunshine hitting the crater rim. I thought it looked like an impact site myself - perhaps there is some confusion about that.

Posted by: ToSeek Oct 9 2009, 11:49 AM

QUOTE (Decepticon @ Oct 9 2009, 04:34 AM) *
Every time I see the impact story on the news, the media tends to over play the impact.


Yeah, the CNN caption was "NASA Attacks the Moon."

Posted by: Elias Oct 9 2009, 11:49 AM

QUOTE (tanjent @ Oct 9 2009, 01:47 PM) *
One of the commentators identified that hotspot as sunshine hitting the crater rim. I thought it looked like an impact site myself - perhaps there is some confusion about that.


That hotspot was visible before the impact - I think its just the crater rim

Posted by: NGC3314 Oct 9 2009, 11:54 AM

Some of us were doing an image sequence with a 0.9m telescope in Arizona, with the moon nearly at zenith. Nothing obvious in Cabaeus as we watched the data come in. I'm turning around now to try aligning and differencing the image to see whether we can tease out a more subtle plume signature.

Edit 40 minutes later - difference imaging shows no plume detection within limits from telescope shake and seeing (which can be improved but not in real time). That makes sense if the SSC only saw a subtle signature.

Posted by: stewjack Oct 9 2009, 11:56 AM

10 a.m. - LCROSS Post-Impact News Conference - AMES (Public and Media Channels)

10 AM Eastern Time
7 AM Pacific
14:00 GMT/UTC I think

Jack

Posted by: Doc Oct 9 2009, 11:57 AM

I too failed to see anything. You should have heard my brother, 'Well, where is it?' mad.gif

Posted by: deglr6328 Oct 9 2009, 11:59 AM

oh well, that was anticlimactic. As it's going to be hours at least before other images are released and with the news channels in full mediagasm mode over the prez' Nobel, I really don't expect any data until next week. g'nite!

Posted by: nprev Oct 9 2009, 12:04 PM

I'm already dreading the headlines: "NASA Moon Bomb A Dud", etc. ad nauseum. Sure hope the science was a success; have to find out after work. G'night/G'morning everyone.

Posted by: Zvezdichko Oct 9 2009, 12:15 PM

I'm very sorry you felt disappointed. I can understand why - no bright flash. But the real treasure could be coming to us.

Posted by: Hungry4info Oct 9 2009, 12:18 PM

QUOTE (Zvezdichko @ Oct 9 2009, 07:15 AM) *
But the real treasure could be coming to us.

That's my stance too. We haven't seen or heard from LRO or HST.

Posted by: mchan Oct 9 2009, 12:24 PM

from discussion on nasaspaceflight forum --

http://www.gargaro.com/MaRvInWaVs/boom.wav

Posted by: Hungry4info Oct 9 2009, 12:25 PM

I recall hearing that science return aside, they would be quickly able to determine if the mission was a success or not. While I have very little doubt that LCROSS will return data, has there been any word from the LCROSS team itself?

Posted by: Astro0 Oct 9 2009, 12:29 PM

From LCROSS shortly after Centaur impact...



Last frame from LCROSS video before it cutout...


....I think that the whole sequence was fantastic. cool.gif
Watching the Moon's surface rush towards us reminded me of the old footage of Ranger heading for impact.
The anticipation/tension of the whole thing was great.
Was anyone else leaning closer to their screen hoping to see something?...ANYTHING!

There's going to be more data here than we can see right now.
Let's wait for the press conference being held in about 90 minutes.

In a way, I'm glad there was no 'flash'....that might convince some media/public that it wasn't a bomb! wink.gif

Posted by: Hungry4info Oct 9 2009, 12:34 PM

Oh definitely, absence of the Centaur impact aside, I definitely enjoyed it. I, too, leaned closer =)

Posted by: nprev Oct 9 2009, 12:35 PM

laugh.gif !, mchan!

Oh, I'm not disappointed personally, and of course the real gold will be in the properly acquired & calibrated data. In all likelihood the popular media's gonna be a bit snarky, though, and that's always not the best for NASA.

I was thinking that this would be a good trick to try on one of Mercury's poles someday, with the caveat that the chase spacecraft would have to do a grazing flyby--not an impact-- & survive at least long enough to play back the observations.

Posted by: MahFL Oct 9 2009, 12:39 PM

I would say it's a safe bet if water is found in a shadowed crater, it's a common thing that could be found in ALL solar systems.

Posted by: Astro0 Oct 9 2009, 12:40 PM

For anyone interested, there is an archived version of NASA TV's coverage http://www.space-multimedia.nl.eu.org/index.php?option=com_docman&task=doc_details&gid=1055&Itemid=.

It's 109mb, I'm downloading it now and will try to put together an edited version of the last few minutes before and after Centaur and LCROSS impact.

Posted by: Hungry4info Oct 9 2009, 12:41 PM

NASA news conference at 10 AM EDT
They've got some 'splaining to do. laugh.gif

Posted by: MahFL Oct 9 2009, 12:51 PM

Maybe they impacted a lunar bog ?

Posted by: Hungry4info Oct 9 2009, 12:53 PM

Quote David Morrison, Director of NASA's Lunar Science Institute"I think we're all a little bit disappointed that we didn't see anything, but 90% of the data has not yet been seen."
http://www.newscientist.com/article/dn17951-spacecraft-kamikaze-smashes-into-moon.html

Posted by: climber Oct 9 2009, 01:00 PM

May be it was a splash, not a kaboum: this has to be liquid water

Posted by: Phil Stooke Oct 9 2009, 01:09 PM

http://www.mmto.org/lcross/

Go here for streamimg video from MMT possibly showing the impact plume. But Palomar reportedly saw nothing.

Phil

Posted by: Hungry4info Oct 9 2009, 01:25 PM

Nothing from Lick
http://www.universetoday.com/2009/10/09/lcross-impacts-moon-science-data-pending/

Posted by: elakdawalla Oct 9 2009, 01:33 PM

QUOTE (Phil Stooke @ Oct 9 2009, 06:09 AM) *
...Go here for streamimg video from MMT...

I saw something on Twitter indicating MMT was out of focus so no useful data was gathered? ...but that's Twitter and could possibly be wrong rolleyes.gif

Posted by: MahFL Oct 9 2009, 01:34 PM

I was watching MMT and the closeup did seem a bit blurry. The other view seemed ok.

Posted by: AndyG Oct 9 2009, 01:40 PM

QUOTE (Hungry4info @ Oct 9 2009, 02:25 PM) *
Nothing from Lick
http://www.universetoday.com/2009/10/09/lcross-impacts-moon-science-data-pending/

I just stacked a few of their frames and can see a bit fat nothing. Which is good, right? smile.gif

Andy

Posted by: Littlebit Oct 9 2009, 01:44 PM

Maybe they missed the target;)

Posted by: Juramike Oct 9 2009, 01:52 PM

Somewhere way back, someone had posted an animated GIF showing a lunar impact as seen through a telescope. There was a tiny flash (you could almost imagine it going "piff").

I'd assumed that vaporizing a football field worth of lunar regolith would've made a bigger flash and a sunlit dust plume.

Guess not....

Posted by: ilbasso Oct 9 2009, 01:56 PM

I was somewhat bemused by the confusion over the commanding being given to the Flight Director in the final 60 seconds before Centaur impact, to change a setting on the NIR instrument. "Was that November IR?" How much time was lost in that communication? Hopefully it didn't affect the collection of data. Just shows the unintended consequences of having two instruments with similar sounding acronyms, NIR and MIR.

Posted by: Astro0 Oct 9 2009, 01:59 PM

Going back over the video, there was something in the infrared images that caught my eye.
I've taken 4 frames and put them in an animated gif.



You can see, almost in the middle here a small dot appear. Bright at the centre and a darker blue around it.
It may just be "noise", but it happens and in the audio on the TV coverage just a moment later they announce Centaur impact.

Not claiming anything here, just pointing it out. I suppose we'll know any minute now as the Press Conference is about to start.

Posted by: AndyG Oct 9 2009, 02:03 PM

Mmmm ... I've seen spacecraft disappear into craters before. laugh.gif


Posted by: elakdawalla Oct 9 2009, 02:14 PM

Oh how I wish Ames was as on the ball as JPL is with media graphics. Any sign of these cool slides anywhere on the Web?

Posted by: Astro0 Oct 9 2009, 02:21 PM

There was a 'flash' cool.gif

Here's the mission's image showing the 'flash' and I think it matches nicely to the spot I noticed in the http://www.unmannedspaceflight.com/index.php?showtopic=6244&view=findpost&p=147654.


Posted by: clad Oct 9 2009, 02:24 PM

I´ve a comment about the poor media coverage of this important event, i think this a important mission, can you imagine if we found water in the moon? all the things we can possible found with this discover? , NASA needs more advertise around the world to obtain more benefits, more support from all of us. The information in our present era is like gold, everybody needs to have it....

I would to say thanks to the people in this web page to keep us informed and post pics from the most important part of the mission, and of course a WELL DONE to NASA for this flawless mission.

Posted by: dilo Oct 9 2009, 02:31 PM

Rough animation from the frames of last 2 minutes of transmission (starting about 2.5min after Centur impact). The very last frames aren't included...


 

Posted by: Juramike Oct 9 2009, 02:38 PM

Interesting comment regarding the integrated spectral data after the initial peak (Centaur impact).
"The observation that the line didn't return to zero is interesting." (paraphrased)

Did we make a smoldering crater?

Posted by: centsworth_II Oct 9 2009, 02:39 PM

QUOTE (Juramike @ Oct 9 2009, 08:52 AM) *
....I'd assumed that vaporizing a football field worth of lunar regolith would've made a bigger flash and a sunlit dust plume....

Are you referring to the LCROSS crater? That was predicted to be 60 meters in diameter. It would take about 15 of those to cover a football field.

To everyone: I hope the press conference has dispelled the uncharacteristic negative attitudes I see expressed in many of the post impact comments.

Posted by: Doc Oct 9 2009, 02:44 PM

Indeed there was a flash. Hardly more than a few pixels. But its there and the UV radiance data being presented proves it. The size is as expected...

Posted by: MahFL Oct 9 2009, 02:48 PM

Yes but the whole episode was over-hyped. Todays public expects to see what they expect to see !
A pixel or 2 on a camera ain't going to do it. As a co-worker said "is that all we get for 79 million ?"


Posted by: centsworth_II Oct 9 2009, 02:51 PM

QUOTE (MahFL @ Oct 9 2009, 09:48 AM) *
A pixel or 2 on a camera ain't going to do it. As a co-worker said "is that all we get for 79 million ?"

I'll paraphrase from the press conference:

'THE SPECTRA IS WHERE THE SCIENCE IS AT.'

We pay for the science, not the spectacle.

Posted by: Juramike Oct 9 2009, 02:54 PM

The difference is between the sudden frisson of an awe-inspiring spectacle compared to the subtle beauty of scientific data analysis.

Posted by: AndyG Oct 9 2009, 02:54 PM

QUOTE (centsworth_II @ Oct 9 2009, 03:39 PM) *
I hope the press conference has dispelled the uncharacteristic negative attitudes I see expressed in many of the post impact comments.


Oh, I think that's a little bit unfair. It had been suggested beforehand that a 10" scope might show a flash and maybe even a debris cloud. The result of the real impact - that even multi-metre-diameter scopes seemingly saw nothing - will be disappointing to the general public. There's the negativity, if any.

To quote the conference, it's the squiggly lines on graphs that'll obviously answer (and raise) the questions, and I doubt anyone here isn't looking forward to the real science results - but (if you want to hear my own bug-bear) I think it's unfair on the conference panel to be wheeled out after a very long night, just a few hours after the event, to be asked questions that they can't in all honesty answer at this time.

Andy

Posted by: Doc Oct 9 2009, 02:57 PM

QUOTE (centsworth_II @ Oct 9 2009, 05:39 PM) *
To everyone: I hope the press conference has dispelled the uncharacteristic negative attitudes I see expressed in many of the post impact comments.


The press is definitely skeptical if you look at the briefing. Someone actually suggested an LCROSS 2!

Posted by: Doc Oct 9 2009, 03:00 PM

QUOTE (centsworth_II @ Oct 9 2009, 05:51 PM) *
I'll paraphrase from the press conference:

'THE SPECTRA IS WHERE THE SCIENCE IS AT.'

We pay for the science, not the spectacle.


Amen to that!

Posted by: centsworth_II Oct 9 2009, 03:04 PM

QUOTE (Doc @ Oct 9 2009, 09:57 AM) *
...Someone actually suggested an LCROSS 2!

This sounds like someone who thinks LCROSS is a good idea -- after having witnessed one. smile.gif

Posted by: dilo Oct 9 2009, 03:18 PM

My version of IR sequence near Centaur impact (16sec total duration in the video)

 

Posted by: centsworth_II Oct 9 2009, 03:21 PM

QUOTE (AndyG @ Oct 9 2009, 09:54 AM) *
...that even multi-metre-diameter scopes seemingly saw nothing - will be disappointing to the general public. There's the negativity, if any.

....I think it's unfair on the conference panel to be wheeled out after a very long night, just a few hours after the event, to be asked questions that they can't in all honesty answer at this time.

OK, maybe I was being too sensitive.

I appreciate the time taken by those very tired panelists to give the post impact briefing. Even that soon after the event, we saw some interesting stuff: The flash, the crater, some yet-to-be-interpreted spectra. A rough time line was given: two weeks for behind doors hypothesis to hypothesis combat, two months to public disclosure of the fight results. A major professional conference in December to reveal detailed result at.

Posted by: briv1016 Oct 9 2009, 03:58 PM

Can someone put up a scale bar on the IR images so we can get a sense of size?

Posted by: djellison Oct 9 2009, 04:00 PM

QUOTE (centsworth_II @ Oct 9 2009, 03:51 PM) *
We pay for the science, not the spectacle.


Where is the 350 ton, 6 mile high, 30+ mile wide plume they predicted that would have been very very obvious from all the great observatory pictures?

What has occurred is not what was predicted. Negativity, from that standpoint is, to a certain extent, justified.

I didn't see the thing live - I was away from TV and Internet. Just got some WiFi, looking at all the pics and vids - and before I even visited UMSF, I said "Hmm - I wonder if anyone else will be saying 'is that it'" an indeed they are.

It's certainly not helped by a scientists with this attitude:

"Will you know if you saw water by this afternoon?" Colaprete: "I probably will but I'm not gonna tell you."

The value is in the science - and that science is yet to be done. BUT - what was seen was not what was forecast by that science team.

Posted by: Paolo Oct 9 2009, 04:04 PM

QUOTE (djellison @ Oct 9 2009, 06:00 PM) *
what was seen was not what was forecast by that science team.


this is what science is all about

Posted by: centsworth_II Oct 9 2009, 04:08 PM

QUOTE (djellison @ Oct 9 2009, 12:00 PM) *
What has occurred is not what was predicted....

Sometimes the best science comes from results of an experiment which don't match predictions. Or in sports parlance, 'that's why we play the game.'

Re: "Will you know if you saw water by this afternoon?" Colaprete: "I probably will but I'm not gonna tell you."
In context, the meaning is clear: Colaprete may know what he sees, but his colleagues will also know what they see and there will be differences. They will take a couple weeks to discuss those differences before making a public statement. He also said that!

Posted by: belleraphon1 Oct 9 2009, 04:10 PM



So some people are angry because nature did not behave the way we thought?

I agree with Paolo.... this IS what science is all about.

Personally I am excited that they got GOOD data. Now let the scientists do their jobs. And let them do it correctly with no rushed results.

Craig


Posted by: elakdawalla Oct 9 2009, 04:11 PM

We all know what he meant, and he did go on to say that he needed to await scientific consensus. But the way he phrased it was unfortunate. I know he was tired and all, so it's hard to blame him, but unfortunately he came across as smirky and smug, and the whole panel seemed to avoid the issue of the lack of a flash, which didn't produce a great impression; I worry the press won't treat the team well.

Posted by: bugs_ Oct 9 2009, 04:13 PM

Shoulda put a bigger "bomb" on it :-)

Posted by: centsworth_II Oct 9 2009, 04:15 PM

QUOTE (bugs_ @ Oct 9 2009, 12:13 PM) *
Shoulda put a bigger "bomb" on it :-)

laugh.gif --- I mean mad.gif

Posted by: MahFL Oct 9 2009, 04:22 PM

A newclear bomb ?

Posted by: djellison Oct 9 2009, 04:29 PM

QUOTE (belleraphon1 @ Oct 9 2009, 05:10 PM) *
So some people are angry because nature did not behave the way we thought?

I agree with Paolo.... this IS what science is all about.


Angry? Certainly not.

A bit disappointed with the early results? The lack of an obvious plume from even the very best ground based observatories? I think so.

Couldn't agree more with the sentiment though - this really IS what science is about. If we got exactly what we expected, then would we really learn anything anyway smile.gif

Posted by: PhilCo126 Oct 9 2009, 04:29 PM

It was a superb opportunity for ground-based observatories, curious to see what Hubble saw...
http://keckobservatory.org/index.php/news/a_new_view_of_the_moon/
(.)

Posted by: MahFL Oct 9 2009, 04:48 PM

I just watched the replay, seems they underestimated the bandwidth needed, also were getting confused as to which camera they were talking about, and the main commentator of course said "I am not sure what we saw, which translates to "we did not really see anthying just now did we.....?".

They seemed pleased at LOS, presumebly confident they hit the Moon !

Posted by: djellison Oct 9 2009, 04:58 PM

Emily, as ever, says the right things, in the right way :
http://www.planetary.org/blog/article/00002157/

Here - a less positive commentary on events
http://jesseknoll.com/blog/?p=270

Posted by: marsophile Oct 9 2009, 05:01 PM

This is more or less consistent with the result from the Lunar Prospector impact. No visible plume there either although a small one was expected. One difference so far is the detection of the sodium line mentioned at the press conference. They did not see even that after the Prospector impact.

http://www.ae.utexas.edu/research/cfpl/lunar/pressrelease/discussion.html

Posted by: MahFL Oct 9 2009, 05:05 PM

The truth surfaces....

""There's not going to be these grand, spectacular images of ejecta flying, kind of what you've seen in animations or cartoons," LCROSS principal investigator Tony Colaprete told reporters Thursday. "It's going to be more of a muted shimmer of light, but that muted shimmer of light contains all the information we need to answer our questions."


I wonder what % of people watching knew about that statement........I did not.

Posted by: DDAVIS Oct 9 2009, 05:35 PM

I think the press conference was premature, people were tired and the data was too tentative, to the point that there was an initial statement that they weren't going to state if there was water found, what the reporters were likely to be there to hear about.
The MIR flash detection image was intriguing, and the adaptive optics image from Palomar was amazing. the Apache point telescopic video was reasonably good quality, but the MMT enlarged view was so awful it shouldn't have been shown. Unfortunately the Ranger style spacecraft image sequences were not shown! Too many squiggly lines were dwelt upon to be appropriate to a non technical audience.
Colaprete said in response to a question 'I see something in the spectrometer data but I can't say anything more than that', then he apparently vacillated in the awareness he had of that data, finishing an exchange of questions thus:
Q:"Will you know later this afternoon...if there's water or ice?" A:"...I probably will but I'm not gonna tell you."
He (presumably unintentionally) looked like he was coyly BSing the press, something you don't want to do. A day of rest and analysis and image preparation would have worked wonders. As it is the info barely crept above the 'noise' in discussions of the event in the popular media. It's hard enough to get people interested in the Moon and gathering reporters prematurely to tell them the big news isn't forthcoming doesn't help.
I am glad to see Ames get more cool missions. I'm sure that the optimum means of getting information out in the aftermath of a successful mission, for which they can be proud, will evolve with experience. The data from various sources will eventually speak for itself and provide a composite view of this rather dramatic experiment.

Posted by: alan Oct 9 2009, 05:39 PM

I remember Deep Impact and was expecting something similar. The observing craft must have been much farther away in this case.

Posted by: jmknapp Oct 9 2009, 05:57 PM

If they did enough analysis to determine they got a sodium signal, why not water? Would that indicate any water signal they might tease out of the data will be weak at best?

Lack of water/ice is consistent with http://www.spaceflightnow.com/news/n0907/06kaguya/ results. The LRO press kit mentioned that in addition to the water theory, the decreased neutron flux seen by Clementine (and I gather Chandrayaan-1) near the poles could also be explained by hydrogen deposited from solar wind, being more stable and able to accumulate in the cold polar regions. So is that now the leading theory?

Posted by: centsworth_II Oct 9 2009, 06:46 PM

I was happy with the press conference. I was happy seeing the squiggly lines even though I don't know what they mean. Being told that they were there, that they contained plenty of information to be teased out over time, was good enough for me. I do not wish to be robbed of such small pleasures by those who would prefer nothing rather than a brief, incomplete story. I'm happy with the preview and my appetite is whetted for the main course when it comes.

I suggest that those who are not happy with incomplete information wait two weeks before reading another story about the mission. Better yet, wait for the release of the preliminary papers in December.

Posted by: elakdawalla Oct 9 2009, 06:58 PM

Did anybody happen to get any screen caps from the NASA TV briefing this morning? In particular I'm looking for this one:


If I recall correctly, the one shown on NASA TV had a more pixelated view of the one in the lower right corner instead of the blobby upsampled version they posted on their website, so that you could tell how the flash showed up in several pixels.

Posted by: marsophile Oct 9 2009, 07:02 PM

After all the pre-flight hoopla, the public need to be given something. CNN has seemingly dropped all mention of the mission because they have nothing to show. At the press conference it was mentioned that the new crater created by the Centaur was seen. Could a picture of the new crater at least be released to the waiting media?

Posted by: elakdawalla Oct 9 2009, 07:10 PM

When they say it "was seen," it was just one pixel. So probably not what CNN really wanted.

Still, they could have done a much better job getting their images to the media. Ames doesn't have JPL's polish when it comes to putting out graphics for media. Right now actually I'm trying to collect all the useful images I can for posting in a more easy-to-browse format, but it'll be too late to help anybody who's got a news deadline today.

--Emily

Posted by: climber Oct 9 2009, 07:25 PM

QUOTE (elakdawalla @ Oct 9 2009, 08:58 PM) *
If I recall correctly, the one shown on NASA TV had a more pixelated view of the one in the lower right corner instead of the blobby upsampled version they posted on their website, so that you could tell how the flash showed up in several pixels.

Yes, I remember seen 3 pixels verticaly but very clear, not blobby.

Posted by: Tman Oct 9 2009, 07:36 PM

QUOTE (elakdawalla @ Oct 9 2009, 08:58 PM) *
Did anybody happen to get any screen caps from the NASA TV briefing this morning?


Someone in a German forum captured several pics. Also http://www.raumfahrer.net/forum/smf/index.php?topic=4075.msg119736#msg119736 you're looking for.

Posted by: djellison Oct 9 2009, 07:53 PM

From HardOCP

QUOTE
"Here’s a little video for those of you that thought NASA crashing a satellite into the moon at more than five thousand miles per hour would be exciting. Next up, video of extreme paint drying."


From Wired.com
QUOTE
NASA's LCROSS Impacts the Moon (No, You Didn't Miss It)


from an IT forum
QUOTE
I was disappointed, I saw no 6 mile high plume.


Comments at Space.com
QUOTE
"This was anti-climactic at best - there was absolutely no visible clue of any impact,"

"Maybe they should change the headline from 'KAPOW!' to 'bloop' - I saw no evidence of an impact at all,"


Toms Hardware
QUOTE
Earlier in the week, we were told it would take around one hour until NASA knew whether or not there was water on the moon. Now things are a little different. The AP cites project manager Dan Andrews who says it will probably be two weeks before scientists will be certain about the possibility of there being water on the moon.


Nothing wrong with LCROSS. Something quite clearly wrong with the expectations put out there before it happened.

Posted by: Sunspot Oct 9 2009, 07:56 PM

Hmmmmm been out all day, just got in and been catching up on events, Had a feeling we might get this reaction if we didn't see lots of "fireworks" lol.

Posted by: elakdawalla Oct 9 2009, 07:58 PM

You are the man, Tman!

Posted by: ElkGroveDan Oct 9 2009, 08:00 PM

QUOTE (djellison @ Oct 9 2009, 12:53 PM) *
Something quite clearly wrong with the expectations put out there before it happened.


http://www.unmannedspaceflight.com/index.php?showtopic=6244&view=findpost&p=147618

Posted by: ollopa Oct 9 2009, 08:23 PM

Can we change the thread? It's about the science/spectroscopy, not about the media. A science thread would be nice, since there IS science and this forum will suffer if it follows the media trail.

Posted by: ollopa Oct 9 2009, 08:34 PM

Is this better, Emily?

 

Posted by: djellison Oct 9 2009, 08:53 PM

QUOTE (ollopa @ Oct 9 2009, 09:23 PM) *
there IS science


When we get some - then we can start a new thread. This was (and continues to be) an as-it-happened discussion thread. When the science comes out (and we were told it is 2 weeks away) then we can have a new thread for it.

Posted by: jmknapp Oct 9 2009, 09:24 PM

Given that they saw sodium in the early results, this item from 1999 concerning natural impactors may be of interest:

http://sirius.bu.edu/moontail/


QUOTE
Boston University astronomers announced today the discovery of an enormous tail of sodium gas stretching to great distances from the moon. The observations were made at the McDonald Observatory in Fort Davis, Texas, on nights following the Leonid meteor shower of November 1998. The tail of sodium gas was seen to distances of at least 500,000 miles from the moon, changing its appearance over three consecutive nights...



http://neo.jpl.nasa.gov/news/news023.html

QUOTE
Sodium reflects sunlight very efficiently and so has become a standard way for space scientists to study gases that are otherwise difficult to see. ...

In trying to determine if this comet-like appearance of the moon occurred only on nights following a strong meteor shower, as happened with the Leonids, the BU team examined some earlier data taken at their site in Texas. During the previous August, similar observations were made, fortuitously on the nights following the new moon of August 21, 1998. "It was there," Dr. Smith said, "several times fainter, but with the same shapes over the same three nights spanning the new moon, just as occurred in November."

Taken together, the August observations without meteors and the November observations with meteors imply that the daily flux of micrometeors that strikes the moon's surface creates an extended tail at all times; it was just so enhanced during the strong Leonid storm that it was observed rather easily.

"What we do not know yet is whether the entire atmosphere of the moon is produced by meteors, or just the small component of fast sodium atoms that can escape from it," Mendillo said.

Posted by: antipode Oct 9 2009, 10:20 PM

Surely what might be useful at a press conference would be to show:

1) The Deep Impact images (yes, apples to oranges comparison, but stay with me)
2) The Smart 1 impact movie (from memory hardly any flash, but clearly visible material in a ballistic trajectory, and yes, I know that was a glancing impact from a smaller impactor)

...and just go - "look, we really didn't know what to expect, we are as surprised as you are about the lack of a visible flash, but its that very uncertainty that has brought us here in the first place, this is still a mysterious area and we are trying to probe those mysteries. And you were/are along for the ride, we are all learning new things at the same time"

P

Posted by: ngunn Oct 9 2009, 10:31 PM

I'd just like to report that the BBC news coverage was very good. The emphasis was on the success of the impacts and data collection process. They reviewed the hoped-for science and mentioned the absence of a visible flash almost in passing. As usual radio was better than TV.

Posted by: glennwsmith Oct 10 2009, 04:07 AM

As someone who has called attention to the LCROSS mission in another thread ("Earthlike Mars?"), and who was in fact expecting the mission to be a "game changer" in terms of immediately clearly identifying water at the lunar south pole, let me express some thoughts that others of my ilk may be feeling.

The basic idea is that a disappointment is best handled by acknowledging it as such -- THEN you can wake the morrow morn with some more hopeful thoughts. As it is now -- due to the hemming and hawing of NASA and the media -- we are still stewing over the question of whether the initial results of the mission were or were not a disappointment -- and of course they were.

NASA absolutely did publish statements to the effect that the impact might be detectable through a 10" telescope, when in fact some of the largest telescopes in the world saw virtually nothing.

The shepherding spacecraft itself detected, as far as publishable images are concerned, only a changed pixel or two, and that in only one of the monitored bands.

And none of this bodes well for establishing the presence of significant amounts of water. I'm not saying that this is now impossible -- I'm just saying that when there is virtually no data in the visible band, there's probably not going to be much in the other bands; not to mention that we were only looking for small amounts of water to begin with.

So c'mon, NASA, help me get over this -- let's admit that the initial results have been a big disappointment -- and then let's carry on from there.

Posted by: nprev Oct 10 2009, 04:43 AM

Well...It's definitely far far far too soon to rush to judgement about any aspect of the science return. Consider the frenetic pace of the data acquisition period, and now the big job of reducing this vast mass of data begins...and only after that's done can analysis begin. "Instant science" JPL-style really only works with pictures, and that aspect of the LCROSS payload was mostly for nav/post-impact localization.

However, it's hard not to say that expectation management was not well performed. Perhaps it should be called the "Kohoutek Effect": an interesting and/or unusual astronomical or space event is oversold in 'ooh-aah' potential to the general public, and the result is disappointment...even worse, a percieved lack of credibility ("But they PROMISED Kohoutek would be the comet of the century!"...or even "Does a fizzled flash mean no water?") As has been stated earlier, it's damn hard to predict the results of a novel experiment or event, and if the outcome WAS known with certainty then it wouldn't really be science.

The lesson that should be learned here for future space would-be spectaculars is beware the Kohoutek Effect. It can be done; JPL's getting pretty good at it. It may explain ESA's PR efforts in part as well; one way to manage expectations is to not foster any, but that's the other extreme from today's experience. There's a balance to achieve.

Wow; that sure was a long way to say "patience, grasshoppers!", huh? smile.gif

Posted by: glennwsmith Oct 10 2009, 05:03 AM

Nprev, Kohoutek may be a better example than you realize! For are not comets bodies of rock and ice which sometimes flare spectacularly and unexpectedly, and sometimes not? And do we not hope the floor of Cabeus to be of the same composition? So maybe there are related phenomenon at work here . . .

Posted by: stevesliva Oct 10 2009, 05:12 AM

While the fizzle nature of this one is sort on an opposite of Deep Impact, my cynicism tells me that what's it's probably going to be most like is the Galileo probe... a we-just-hit-the-wrong-place-and-we're-not-changing-the-models kind of sentiment. It's hard for me to put a happy face on that sort of result. And everything worked perfectly in both cases! Sigh. Ah well, if this sort of thing went by the book, it'd be pretty boring, too.

Posted by: Hungry4info Oct 10 2009, 05:55 AM

I'm pretty sure they didn't know what to expect as far as the kind of plume seen. I'm getting the feeling that the media over-hyped this (and the animations we were shown didn't help much either). Science isn't just pretty pictures. I'm quite happy-faced about the spectroscopy. Even if there wasn't a wonderful ka-boom, there's still great data gathered, and I look forward to seeing the results of this mission.

Posted by: djellison Oct 10 2009, 07:58 AM

QUOTE (Hungry4info @ Oct 10 2009, 06:55 AM) *
I'm pretty sure they didn't know what to expect as far as the kind of plume seen.


Then why did they put out figures? 350 tons, 6 miles high, 30 miles across, 10-12 inch telescopes.

Which leads to dissapointment when..
QUOTE
It turns out no telescope, even the giant Keck and Gemini observatories in Hawaii, saw obvious signs of the impact in visual and infrared imagery.
spaceflightnow.com

The media (apart from using the word bomb a lot) seemed to accurately retell the story that LCROSS told them in press releases etc.

It will be scientifically interesting to find out how or why the predictions were so very different to reality.

Posted by: nprev Oct 10 2009, 08:10 AM

Yeah...that really is a million-dollar question. Hell, amateurs with modest scopes have picked up flashes from shower meteor hits (particularly the Leonids, IIRC) before, which are really small & really fast but nowhere close to that Centaur in terms of impact energy.

Somebody half-jokingly said something about it being gulped up by a deep dust pile. That's almost beginning to sound plausible!

Posted by: PhilCo126 Oct 10 2009, 09:35 AM

Although no spectacular impact plume was observed, some reports:
(Nothing so far on IRTF and Lick observatory websites)

Keck 10.0 m
http://keckobservatory.org/index.php/news/a_new_view_of_the_moon/

Hubble Space Telescope 2.40m
http://hubblesite.org/newscenter/archive/releases/2009/26/full/

Palomar 5.00m
http://palomarskies.blogspot.com/


Posted by: Fran Ontanaya Oct 10 2009, 10:50 AM

I didn't expect much.

"When you kick the surface, [the dust goes out in] a little fan which, to me, is in the shape of a rose petal," recalls Armstrong. "There's just a little ring of particles--nothing behind 'em--no dust, no swirl, no nothing. It's really unique."

Posted by: kenny Oct 10 2009, 11:37 AM

If the rocket stage happened to impact on a surface which was far off the horizontal, the ejecta plume coming out would be substantially less than predicted. For instance, an impact into the side of a cliff or steep slope, or the side of a big boulder, would see most of the initial ejecta thrown downwards. Only a small part of the rebound from that would end up exiting the crater, with greatly reduced energy. This might explain the lack of observed plume.

Of course, the chances of this also happening to the chaser satellite are low. However, given its much smaller size, I'm not sure what the initial expectations were of a plume from that, if any.

Posted by: Greg Hullender Oct 10 2009, 03:06 PM

I'd hate it if NASA got so conservative that they didn't alert people to the possibility of something spectacular. All they really needed to do here was to say, up front, "Well, there's a possibility that no one will see anything from the ground, but there's ALSO a possibility that it'll be visible in telescopes as small as 10 inches, so it's worth taking a chance and watching." I'll bet a dollar to a doughnut there were scientists who strongly advised NOT hyping this, given the uncertainties, but they were overruled by PR types.

I can't entirely blame the PR guys, since public support is essential for funding, but it wouldn't have been THAT hard for them to hedge a little bit. Heck, someone once tried to explain to me why people watch things like football, basketball, baseball, etc. by saying that sports are fun to watch because "no one knows what will happen." Putting in some uncertainty in their claims might make these events MORE popular.

@nprev are we showing our age by remembering Kohoutek? Even a Geraldo reference seems dated now! :-)

--Greg

Posted by: scalbers Oct 10 2009, 03:27 PM

QUOTE (nprev @ Oct 10 2009, 08:10 AM) *
Yeah...that really is a million-dollar question. Hell, amateurs with modest scopes have picked up flashes from shower meteor hits (particularly the Leonids, IIRC) before, which are really small & really fast but nowhere close to that Centaur in terms of impact energy.

Somebody half-jokingly said something about it being gulped up by a deep dust pile. That's almost beginning to sound plausible!


Of course the meteor hits might be easier to see from Earth since they wouldn't usually be hidden from direct view in the floor of a crater. On the other hand the shepherding craft should have seen more having that direct view.

And as a colleague asked me, if the Centaur was oriented sideways, would it be less likely to be buried?

Posted by: Hungry4info Oct 10 2009, 03:43 PM

If I understood correctly, a sideways hit (as well as a hit where the Centauri would be vertical) were unfavorable. An angled hit would allow for more ejecta. As for impact flash? No idea.

Posted by: Paolo Oct 10 2009, 03:58 PM

QUOTE (Hungry4info @ Oct 10 2009, 05:43 PM) *
An angled hit would allow for more ejecta.


Not really comparable, but Lunar Prospector (far less mass, less speed --> less kinetic energy) made an almost grazing hit in 1999 but it also failed to raise any detectable plume

Posted by: scalbers Oct 10 2009, 04:18 PM

I think there are two variables here, one is the trajectory of the spacecraft, and the second (that I was wondering about) is the attitude or orientation of the spacecraft.

Posted by: Elias Oct 10 2009, 06:52 PM

With an impact in such a permanently shadowed region, how high should the plume ejecta rise so that they can reflect sunlight? Was there any prediction for that? I just think there is not much light there to reflect the plume dust, even if the plume is extended. Still, the detectors at other wavelengths should have seen more...

Posted by: Reed Oct 10 2009, 11:43 PM

QUOTE (scalbers @ Oct 10 2009, 08:18 AM) *
I think there are two variables here, one is the trajectory of the spacecraft, and the second (that I was wondering about) is the attitude or orientation of the spacecraft.

As kenny said, the details of the particular terrain it hits matter too. This was mentioned in the post impact press conference.

It appears the LCROSS team believed there was a high probability that it would visible in modest size telescopes, but I'm sure they knew other outcomes were possible. They probably didn't communicate this as well as they could have, but such subtlety would almost certainly have been lost on the press anyway.

Elias: There definitely were predictions and models. You can find some of them on the lcross site.

Posted by: tedstryk Oct 11 2009, 12:22 AM

QUOTE (glennwsmith @ Oct 10 2009, 05:07 AM) *
So c'mon, NASA, help me get over this -- let's admit that the initial results have been a big disappointment -- and then let's carry on from there.

Without time to digest the science result, that would be an absurd statement to make . Given that a bright plume was considered a possibility, NASA would be taken flack had it happened and the didn't alert people. Many people thought SL-9 would fizzle. What if NASA had played it down because we might not see much?

Posted by: elakdawalla Oct 11 2009, 01:37 AM

As (sort of) a member of "the media," I feel like I should speak up here. I had figured that people with telescopes on the smaller end of the scale probably wouldn't see anything. But given that there was a big effort to organize amateur astronomers (or at least provide plenty of relevant, up-to-the-minute information to them), and the organized events run at bigger observatories, I never, ever, once imagined that the biggest telescopes on the planet wouldn't be able to see anything. Frankly I'm still surprised and confused about the fact that even Palomar didn't see squat. I think it's totally reasonable to be surprised about that.

From my point of view, reporting on this event, I was never particularly interested in the view from telescopes of any size. I was wholly focused on the shepherd spacecraft. Everything seemed to function spectacularly. And yet there was basically no indication of any impact on the screen. Even the people doing the color commentary for NASA TV were confused about that. We were all geared up for a climax that never came.

When you get excited, and expect something that doesn't come, you're disappointed. That's basically the definition of disappointment!! And I think there's no incompatibility between understanding that the mission was successful and still being disappointed about the lack of any sign that the impact happened during the live event.

--Emily

Posted by: nprev Oct 11 2009, 01:52 AM

Seemingly, the PR impact has been greater (if in an unexpected way) then that of the physical event...didn't realize that the title of this thread would become a pun... rolleyes.gif

Posted by: Shaka Oct 11 2009, 01:58 AM

Maybe LCROSS was swallowed up by hundreds of meters of 'snow'.
blink.gif

Posted by: MarsIsImportant Oct 11 2009, 02:38 AM

...swallowed by snow or some other unexpected surface feature in the shadow was my first impression. Maybe the combination of cold and H2O condensation inside the shadowed crater created a cushion type textured surface that is very deep. Who knows?

The impact did occur and on target, but no fireworks. There has to be a logical explanation.

Posted by: mcaplinger Oct 11 2009, 02:59 AM

QUOTE (MarsIsImportant @ Oct 10 2009, 07:38 PM) *
The impact did occur and on target, but no fireworks. There has to be a logical explanation.

The simplest explanation, completely consistent with all the available data (once you strip off the hype) is that there were simply no significant volatiles at the impact site.

Posted by: Shaka Oct 11 2009, 03:17 AM

But shouldn't there have been "fireworks", even without ice?

Posted by: elakdawalla Oct 11 2009, 03:36 AM

IIRC the reason the Deep Impact impact was so spectacular was because of the amount and fineness of the dust. The lack of any visible curtain probably tells us something pretty significant about the nature of the substrate but I'm not sure what it is. Mcaplinger, correct me if I'm wrong, but I don't think it's the presence or absence of volatiles (which weren't expected to have been present at more than a couple percent as far as I understand) but the grain size and porosity of the material at the impact site that contributes most to the size of the ejecta curtain. When Deep Impact was about to happen, there was lots of discussion of Peter Schultz's experimental work on impacts into different kinds of materials, and I think their biggest concern was that they'd impact into a cohesionless target where there hardly be an ejecta curtain at all, just sort of a backward squirt out a deeply punched transient crater. (I think that was a "compression-controlled" impact as opposed to "gravity-" or "strength-controlled."

Funny, while I was researching that last sentence I was reminded of the manner in which the Deep Impact impact was unexpected. The Society ran a contest to see who could guess closest to the actual size of the impact crater, but the Deep Impact ejecta curtain turned out to be so spectacularly large and dusty that they were never able to see the crater. So we were forced to pick at random an entrant who'd been among the many who'd predicted a size between 100 and 250 meters, which pissed a lot of people off. Guess that goes to show you that making predictions is a bad idea smile.gif

--Emily

Posted by: Holder of the Two Leashes Oct 11 2009, 03:52 AM

I hope the Society kept the list. In mid-February 2011, you might have another chance to make the award a second time, albeit belatedly.

Posted by: mcaplinger Oct 11 2009, 05:11 AM

QUOTE (elakdawalla @ Oct 10 2009, 08:36 PM) *
Mcaplinger, correct me if I'm wrong, but I don't think it's the presence or absence of volatiles (which weren't expected to have been present at more than a couple percent as far as I understand) but the grain size and porosity of the material at the impact site that contributes most to the size of the ejecta curtain.

The size, perhaps, but not necessarily the visibiliity. See http://lcross.arc.nasa.gov/docs/Colaprete.LCROSS-overview.ppt page 14 for a discussion of the "vapor cloud" which contributes in some not-well-explained way to the impact visibility through excitation of OH- and H2O+.

I read http://www.lpi.usra.edu/meetings/leagilewg2008/presentations/oct28pm/Bart4050.pdf but it's not clear there how volatiles were expected to contribute to plume visibility; all of the predictions were based on 1%.

At any rate, I don't claim to be especially knowledgeable on this topic and could well be wrong, but to my eye these results aren't lending a lot of credence to the already fairly poor case, prior to LCROSS, for there being a lot of ice at the lunar poles.

Posted by: nprev Oct 11 2009, 05:37 AM

That's a pretty good point re excitation of ions; if there were a lot (& I mean a LOT) of volatiles in the impact plume, you'd expect it to light up like a neon sign once it was exposed to the solar wind.

I think the issue is whether there was a plume of any significance or not, though. Evidence thus far seems to indicate that there wasn't, and I'm not sure if the often-cited hypothetical 1% H2O content would have been a player in that at all if it does in fact exist; seems like too small a concentration to affect the material properties of the soil (if the Centaur in fact hit soil) at the impact site.

All we really seem know right now is that at that specific place where the impact occurred there was less material ejected then expected, reason unknown. The spectroscopic data should shed some light (ta-da, da!) on the ejecta's chemical composition but probably won't yield much information about its pre-impact physical properties. And when the dust finally settles (please, somebody stop me!), all the data & analysis will again only be truly relevant to that very specific point on the Moon's surface, and it might be erroneous to extrapolate the results as representative of the entire South Polar region.

Posted by: MarsIsImportant Oct 11 2009, 06:44 AM

I just thought of something. Some say that there wasn't much ejecta because maybe LCROSS hit something very hard like a boulder. Well, the hydrogen signature is definitely there in that crater. Most believe it is water ice...perhaps only 1% of H2O in the soil. That's an assumption, right? What if the concentration is a lot greater than that?

Water ice in space is much different than here on Earth. It cannot form crystals in a vacuum. We call this form 'amorphous ice'. It is very much like hard glass only far colder. Imagine LCROSS hitting a block of hard glass that is 50 or more meters thick. It might as well as hit a solidified lava flow. Am I right?

I'm sure there would have been some damage to the block. But the forces involved in the impact would have been directed differently than expected. Wouldn't there be a lot less ejecta going upward in such a case? Wouldn't most of the forces be directed more horizontally and the ejecta would be less likely to get above the rim? I'm not an expert on impact dynamics, so help me out on this one.

Posted by: jmknapp Oct 11 2009, 11:09 AM

LCROSS could only be considered a failure in the sense that the Michelson-Morley experiment to detect "luminiferous ether" was a failure. Rather, both experiments were executed flawlessly and disproved the existence of the hoped-for substance (in this case volatiles). So disappointment rather than failure is indeed the bottom line.

Posted by: imipak Oct 11 2009, 11:18 AM

QUOTE (MarsIsImportant @ Oct 11 2009, 07:44 AM) *
Imagine LCROSS hitting a block of hard glass that is 50 or more meters thick.


A 50m thick layer of ice would have been unambiguously detected by one of the many previous spectrometers and other instruments to overfly the poles.

Posted by: centsworth_II Oct 11 2009, 02:25 PM

QUOTE (jmknapp @ Oct 11 2009, 07:09 AM) *
...executed flawlessly and disproved the existence of the hoped-for substance (in this case volatiles). So disappointment rather than failure is indeed the bottom line.

Everyone here should agree: Good science and successful experiments tell us what is there, not what we wish was there.

However, I think you're premature in saying what the experiment has proved or disproved. No visible debris cloud does not equal no volatiles. That information is found in the spectroscopic data which has yet to be reported on. What I got from the press briefing was that spectra of the flash were obtained. I don't know if those are ideal or sufficient for detecting volatiles. Also, although there was no visible cloud, I don't know if it has been stated that there was no spectrographic data collected in the aftermath of the flash from invisible products of the impact.

Posted by: MarsIsImportant Oct 11 2009, 02:47 PM

I think we should wait for the results before making any conclusions. I've read that they obtained good data and need to process it thoroughly before making anything public.

There really is no reason to play a guessing game until we have all the information.

Posted by: Reed Oct 11 2009, 09:42 PM

QUOTE (jmknapp @ Oct 11 2009, 04:09 AM) *
Rather, both experiments were executed flawlessly and disproved the existence of the hoped-for substance (in this case volatiles).

I don't see how a negative result from LCROSS would unambiguously disprove volatiles at the poles in general. Since we don't have any instruments that resolve down to the scale of the crater, we can't say whether we hit a representative sample. The LEND data already suggests that hydrogen concentration is variable in the shadowed craters at larger scales, and it seems reasonable to assume this would continue to smaller scales. If good spectra has been obtained from both the centaur and spacecraft impacts, that would help, but AFAIK we don't know that yet.

A positive result would tell us, yes, there is at least X percent in some places. A negative by itself doesn't tell us much, although the rest of the data might.

Posted by: JRA Oct 12 2009, 03:36 AM

I didn't see it mentioned on the last several pages, but apparently the LRO detected an impact plume from LCROSS with its LAMP instrument and Diviner detected the impact crater. So it sounds like there was a plume created from the impact, but just not large enough to be seen from Earth I suppose. Hopefully they release the data from LAMP soon, if they haven't already

Some links.
http://lroupdate.blogspot.com/
http://www.diviner.ucla.edu/blog/?p=184

Posted by: glennwsmith Oct 12 2009, 04:21 AM

Although I must agree with Imipak that a 50m thick layer of ice would have been unambiguously detected by now, I like the way marsisimportant is thinking in his post about the strange physics that may go on in the vacuum and cold of the moon, which physics might prevent a ejecta cloud from forming -- and precisely because it DOES contain a lot of water.

For water, as we all know, does have a lot of enigmatic qualities from a physics standpoint.

Indeed, what happened with LCROSS might be akin in terms of science history to the recent discovery of water across the sunlit surface of the moon. Yes, theoretical physicists might know that high speed protons can interact with the oxygen atoms in rock to form water, but apparently nobody had thought of applying this arcane physics to the surface of the moon to predict the presence of water.

Likewise, there may be some arcane physics -- possibly involving water! -- which accounts for the non-appearance of the ejecta cloud. In fact, Emily recently mentioned in another context that the water molecule is very sticky.

Posted by: Mogster Oct 12 2009, 10:41 AM

I haven't noticed negativity in the UK media, some "Americans bomb the moon" headlines but that's to be expected over here.

Most of the after action reports seem to be highlighting the unknown factor, why didn't it produce visible results as expected? Which is OK imo.

Posted by: djellison Oct 12 2009, 10:58 AM

The live coverage I heard on Radio 5 Live here in the UK was bordering on cringeworthy. The women presenter was dismissive, demanding and to be honest, offensive to the on-air expert.

Posted by: Sunspot Oct 12 2009, 11:32 AM

They're like that with any thing to do with science - most BBC journalists come from the world of the arts or politics. Coverage of the '99 eclipse was appalling.

Posted by: Fran Ontanaya Oct 12 2009, 06:25 PM

QUOTE (glennwsmith @ Oct 12 2009, 06:21 AM) *
Likewise, there may be some arcane physics -- possibly involving water! -- which accounts for the non-appearance of the ejecta cloud.


Water is important for us, but I feel like it is being portraited as the only kind of solidified substance we would expect to find there besides regular dust.

There is plenty of things that become volatile during the Lunar day and can freeze below 40 Kelvin. Ignoring any other constraints, it could aswell have hit a solid slab of Argon.

Posted by: Phil Stooke Oct 13 2009, 04:32 PM

From the Facebook page:

LCROSS Lunar Impactor Mission.
The LCROSS science team met on Saturday and Monday to discuss the results and start putting together the story. In addition, further reports came in from the EBOC (Earth Based Observational Campaign). As true to the scientific method, data has been gathered, positive & null results are both valuable. Now is the time for analysis and comparisons with theory to explain the story. The team anticipates to report at the LEAG in Houston coming up in a few weeks and at the AGU in San Francisco in December. Meanwhile, check our mission page http://www.nasa.gov/lcross for the latest updates.
-LCROSS Facebook Team.

Posted by: Ron Hobbs Oct 13 2009, 05:23 PM

Paul Spudis has an interesting take on the potential science at his Air & Space magazine blog:

http://blogs.airspacemag.com/moon/2009/10/12/lcross-a-mission-to-hyperspace/

Posted by: jmknapp Oct 14 2009, 10:54 AM

QUOTE (Ron Hobbs @ Oct 13 2009, 12:23 PM) *
Paul Spudis has an interesting take on the potential science at his Air & Space magazine blog:

http://blogs.airspacemag.com/moon/2009/10/12/lcross-a-mission-to-hyperspace/


The http://www.nasa.gov/mission_pages/LCROSS/main/diviner_impacts.html of the impact site show that the LCROSS team made a bullseye, right in the coldest part of the crater. Spudis' claim that a negative water result says nothing, and his trashing of the whole LCROSS concept sounds more like wishful thinking, i.e., we know the water is there somewhere, negative evidence to the contrary notwithstanding. So, rovers and "hoppers" are proposed as the next best hope, that should have been done in the first place, etc.

If no water exists at the coldest part of a permanently-shadowed crater ("cold trap"), by what mechanism would it collect in any appreciable quantity elsewhere?

Posted by: djellison Oct 14 2009, 11:19 AM

He was playing devils advocate. If LCROSS turns out dry - then the logical conclusion is to find some other means to explain the Hydrogen reading. The illogical conclusion that may well play out from supporters of the ice hypothesis is that it hit the wrong place and is not a negative. Paul's take on LCROSS is one I share.

Posted by: jmknapp Oct 14 2009, 12:08 PM

QUOTE (djellison @ Oct 14 2009, 06:19 AM) *
If LCROSS turns out dry - then the logical conclusion is to find some other means to explain the Hydrogen reading.


Here's an observation from one paper, http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V3S-47HPDNV-2&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1047887297&_rerunOrigin=google&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=dc6eb10675ac74fb4f91c53249125cba:

QUOTE
However, the Lunar Prospector
Neutron Spectrometer (LPNS) has detected hydrogen enrichments at both lunar poles (Feldman et al.,
1998; 2000). Although the neutrons are sensitive to atomic composition, the method can not distinguish
between molecular forms of hydrogen. Therefore the hydrogen detected at the lunar poles could be in
hydroxides in the regolith, adsorbed water, molecular hydrogen, or interstitial atomic hydrogen.


In that simulation, they calculate that 7 million years would be required to for the solar wind to transport enough hydrogen to the poles to account for the LPNS reading. That would include atomic hydrogen (2.3%), molecular hydrogen (21.7%), hydroxide (66.7%) and water (6.8%).


Posted by: nprev Oct 14 2009, 02:03 PM

Quick disclaimer: I'm not biased towards a wet or dry polar area; let the chips fall where they may based on the evidence.

That said, we need much more data.

This debate strongly reminds me of the view of Mars post-Viking & MPF until the MERs (really, Oppy) & Phoenix: 'dry & rocky everywhere, it's all the same'. This is not a perfect analogy, but the base concept is the same. There seems to be a fundamental human tendency to draw general conclusions based on limited data (call it the 'first impressions' effect?)

Just throwing that out there as a cautionary note. We now return to our regular programming. smile.gif


Posted by: Holder of the Two Leashes Oct 14 2009, 03:33 PM

One thing I'm not understanding here: why is it so important that the hydrogen has to be present in the form of water to be valuable? These spacecraft are picking up some kind of hydrogen signal. If it's in the form of solar wind deposited hydrogen, then fine. You can roast it out of the rocks and you have your ready made rocket fuel, without the step of having to break it out of the water. If you need water, then just combine the hydrogen with readily available lunar oxygen. And if it's a case of scientific study, well, you just go with whatever is there.

We don't yet know if there is any appreciable water. We do know the hydrogen is there.

Posted by: djellison Oct 14 2009, 03:55 PM

QUOTE (Holder of the Two Leashes @ Oct 14 2009, 04:33 PM) *
We do know the hydrogen is there.


We don't know what form it's in. It may be in a form that's hard to liberate. Furthermore - hydrogen on its own, isn't that useful* It's incredibly light so it's not much of a burden for space flight (consider the Mars Direct ISRU numbers). You tend to need something heavy (oxygen) to do something with it. If it's vast swathes of actual ice down there - then we have rocket fuel, air and water for future crews. If it's just hydrogen, you've still got to take 7/8ths the mass with you.

* apart from filling balloons - but that's not too useful on the moon smile.gif

Posted by: Holder of the Two Leashes Oct 14 2009, 04:42 PM

But the oxygen is there, too. And there have been lots of studies and pilot projects on how to get it. I still think, that whatever form, suitable seperation techniques would exist to get the hydrogen. Chemically bound to the rocks would be the hardest, but would also seem to be least likely, at least at the poles.

Posted by: marsophile Oct 14 2009, 05:02 PM

Some more info here:

http://dsc.discovery.com/news/2009/10/14/lunar-crash-temperature.html

Posted by: djellison Oct 14 2009, 05:10 PM

QUOTE (Holder of the Two Leashes @ Oct 14 2009, 05:42 PM) *
But the oxygen is there, too.


Good point.

Posted by: centsworth_II Oct 14 2009, 05:23 PM

A lot is being made of wishful thinkers' bias in explaining away any negative water results. Maybe Mars first bias explains the speed with with which some are grasping such negative results -- before they are released.

Posted by: Juramike Oct 14 2009, 06:37 PM

QUOTE (marsophile @ Oct 14 2009, 12:02 PM) *
http://dsc.discovery.com/news/2009/10/14/lunar-crash-temperature.html


From the article:

QUOTE
"I am preparing a public release that I hope to get out in the next couple of days," lead scientist Anthony Colaprete wrote in an email to Discovery News.


I'm gonna wait for the release...

Posted by: Spin0 Oct 15 2009, 06:54 AM

Interesting article about water on the Moon: http://www.thespacereview.com/article/1485/1


In 1978 Russians found water in samples brought back by Luna-24. In 1976 Luna-24 landed in Mare Crisium and drilled a core sample from about 2 m deep in Lunar surface. Their article "Water in the regolith of Mare Crisium (Luna-24)" was published in a Russian publication Geokhiimia but seems to have gone ignored.

Here's a link to the abstract: http://adsabs.harvard.edu/abs/1978Geokh......285A

QUOTE
IR diffuse reflection and IR transmission studies of lunar soil samples obtained by Luna-24 are described. Approximately 0.1 wt% water was detected in samples from a depth of 143 cm, and the amount of water seemed to increase with depth, although the extent of change was almost at the limit of technique sensitivity.


Makes it even more sad to think that to day Luna-24 still is the last soft landing on the Moon.

Posted by: abalone Oct 15 2009, 12:16 PM

Entire post of blue-sky engineering culled. See rules. - ADMIN

Posted by: abalone Oct 15 2009, 12:31 PM

QUOTE (abalone @ Oct 15 2009, 10:16 PM) *
Entire post of blue-sky engineering culled. See rules. - ADMIN

I cant understand why this post has been culled, fission engines using hydrogen as a working fluid were in the design stage in both the USA and Soviet Union in the 1950s and 60s. the Russians even tested one. If this is blue-sky then someone is lacking a bit of faith that any progress is going to be made
Seems to me there is more blue-sky engineering in harvesting water from the lunar poles than building these engines

"A nuclear engine was considered for some time as a replacement for the J-2 used on the S-II and S-IVB stages on the Saturn V and Saturn I rockets. Originally "drop-in" replacements were considered for higher performance, but a larger replacement for the S-IVB stage was later studied for missions to Mars and other high-load profiles, known as the S-N. Likewise the Soviets studied nuclear engines for their own moon rockets, notably upper stages of the N-1. However, neither design had progressed to the point where they were ready to test before the space race was ostensibly over.

To date, no nuclear thermal rocket has flown, or even reached a stage of development where it could be. The Russian nuclear thermal rocket RD-0410 went through a series of tests on the nuclear test site"
http://en.wikipedia.org/wiki/Nuclear_thermal_rocket

Posted by: abalone Oct 15 2009, 12:49 PM

QUOTE (djellison @ Oct 15 2009, 01:55 AM) *
We don't know what form it's in. It may be in a form that's hard to liberate. Furthermore - hydrogen on its own, isn't that useful* It's incredibly light so it's not much of a burden for space flight (consider the Mars Direct ISRU numbers). You tend to need something heavy (oxygen) to do something with it. If it's vast swathes of actual ice down there - then we have rocket fuel, air and water for future crews. If it's just hydrogen, you've still got to take 7/8ths the mass with you.

* apart from filling balloons - but that's not too useful on the moon smile.gif

Ill try to repeat my original post and see if it get through this time

Hydrogen used as a propellant in a fission rocket has a much higher impulse than when you waste it by burning it with oxygen. Designs for these do exist, you would only have to carry a couple of tens of kgs of uranium and it does not have the same emotive radiation hazard that it would have if launched from Earth. Even at 6.8% water there would be plenty to drink and breathe

And would like to add in support

"Usually, with hydrogen propellant the solid-core design is expected to deliver specific impulses (Isp) on the order of 800 to 900 seconds, about twice that of liquid hydrogen-oxygen designs such as the Space Shuttle main engine."
http://en.wikipedia.org/wiki/Nuclear_thermal_rocket

Posted by: stewjack Oct 15 2009, 01:31 PM

QUOTE (abalone @ Oct 15 2009, 07:31 AM) *
I cant understand why

I didn't see your original post, but I suspect you are off-topic. HINT: It has been my experience that the longer or more complex the post, the stronger the requirement for being on topic.

IMO: You just crossed a subjective line - by starting a discussion of nuclear propulsion in a LCROSS impact results thread. Technically the "usefulness of H2O" discussions were probably off-topic, but as in U.S. Football, it is always the player who retaliates for a foul blow that ends up getting the penalty. rolleyes.gif

Jack
If this post is deleted for being off-topic at least it is my first offense. laugh.gif

Posted by: dilo Oct 15 2009, 01:53 PM

QUOTE (Spin0 @ Oct 15 2009, 06:54 AM) *
In 1978 Russians found water in samples brought back by Luna-24. In 1976 Luna-24 landed in Mare Crisium and drilled a core sample from about 2 m deep in Lunar surface. Their article "Water in the regolith of Mare Crisium (Luna-24)" was published in a Russian publication Geokhiimia but seems to have gone ignored.

Thanks Spin0! This makes me disappointed, did NASA/scientific community deliberately ignored these findings because they are considered unreliable or... rolleyes.gif

Posted by: Phil Stooke Oct 15 2009, 02:00 PM

Not really - they had the same findings from Apollo samples. Everyone thought it was contamination.

Phil

Posted by: marsophile Oct 15 2009, 03:43 PM

QUOTE (Phil Stooke @ Oct 15 2009, 07:00 AM) *
Not really - they had the same findings from Apollo samples. Everyone thought it was contamination.


If they thought it was contamination, then how did they reach the conclusion that the Moon was "bone dry"? The contamination would mask any negative result. The interpretation should have been that the tests were inconclusive, rather than a definite finding of no water.

Posted by: MarsIsImportant Oct 15 2009, 04:29 PM

So instead of doing the hard science to find out whether the results were contaminated, everyone just assumed they were. A startling discovery 30 to 35 years ago that would have changed the paradigm for space exploration back then was simply shrugged off as an errant reading, not once but twice from two separate sources and experiments. They simply did not believe the data.

Unfortunately this type of thing is not all that uncommon, just normally a little less dramatic. Pride comes before the fall.

Posted by: Phil Stooke Oct 15 2009, 04:50 PM

I agree that people may have rejected their findings too quickly, but it wouldn't have 'changed the paradigm'. The amounts we are talking about, a molecule or two thick, will make no difference at all to anything. Only the possible concentrations at the poles have the chance to change the paradigm.

As for the bone dry thing, the lunar surface even with these molucules adhering to it is dryer than any bone. That old conclusion referred to chemically or geologically active water, and it's still true today. The problem here is overhyping of the recent results. Water, yes, but not as we know it, or in any useful amount. LCROSS results may still be different.

Phil

Posted by: dilo Oct 15 2009, 04:58 PM

QUOTE (Phil Stooke @ Oct 15 2009, 04:50 PM) *
The amounts we are talking about, a molecule or two thick, will make no difference at all to anything.

Phil, I think that 0.1 wt% water isn't so negligible, even though not very usable for human activities, perhaps... however, let's consider also the amount of water seemed to increase with depth!

Posted by: MarsIsImportant Oct 15 2009, 05:13 PM

I noticed the depth thing too. That is potentially significant. We won't know for sure one way or another until more exploration is done. A lot of that exploration may depend upon the results from this LCROSS mission. I hope we get it sooner rather than later.

Posted by: Sunspot Oct 16 2009, 06:53 AM

Interesting article from New Scientist.

"Was moon-smashing mission doomed from the start?"

http://www.newscientist.com/article/dn17991-was-moonsmashing-mission-doomed-from-the-start.html


Posted by: Phil Stooke Oct 16 2009, 12:45 PM

Part of the problem with the water story is that we are getting inconsistent statements. As I understand it the water is only a few molecules thick on the very surface of the regolith, and much of it leaves the surface when heated during the day, then reforms as the sun sets. That is very little water. Then we have statements about getting a glass of water out of a tonne of regolith - or whatever the specific amount is. I think these are not compatible, and the only way I can reconcile them is to say that the tonne of regolith is not dug up in one place but scraped in a layer 1 mm thick over a large area. In other words the bulk regolith is 'bone dry' and a very thin surface layer has all the water. I might be wrong here, but I think not. As far as I know the water detected by M3 is not chemically active - not producing clay minerals in significant quantities, for instance. Obviously we need a lot of follow-up studies of this, but it does seem to me that the water story has been exaggerated in the media.

Phil

Posted by: djellison Oct 16 2009, 12:57 PM

QUOTE (Phil Stooke @ Oct 16 2009, 01:45 PM) *
d the only way I can reconcile them is to say that the tonne of regolith is not dug up in one place but scraped in a layer 1 mm thick over a large area. In other words the bulk regolith is 'bone dry' and a very thin surface layer has all the water.


That's the idea I got as well - and is the figures I used when estimating just how useful it might be.

Posted by: Greg Hullender Oct 16 2009, 05:04 PM

But now I think we do know that the various probes only claimed to have measured the top mm or so -- I don't see anyone claiming to have proven the H2O was limited to the top mm.

Given a porus medium being subjected to a daily barrage of hydrogen, and knowing how motile hydrogen is, I find it difficult to believe that it wouldn't permeate the regolith to considerable depth. The regolith should be in equilibrium with respect to hydrogen content -- losing as much as it gains in any given day -- but given a slight preference to move down (caused by gravity) plus a tendency of anything very far below the surface to stay put (caused by lower temperatures) I can't see how that equilibrium would be reached with hydrogen limited to just the top mm.

As everyone says, with any luck we'll see some exciting real data in a few months. And perhaps this will excite some interest in lunar rovers with some digging capability.

--Greg

Posted by: climber Oct 16 2009, 07:12 PM

Wanna get the water story of the Moon? Get Oppy from Mars and put her there.

Posted by: elakdawalla Oct 16 2009, 07:26 PM

New data and images released today, but still no word on what the spectrometer detected.
http://www.nasa.gov/mission_pages/LCROSS/main/LCROSS_impact.html
http://www.nasa.gov/mission_pages/LCROSS/main/LCROSS_impact_images.html

--Emily

Posted by: MahFL Oct 17 2009, 02:10 PM

I am sorry but that first image seems to me rather underwhelming.

Posted by: ugordan Oct 17 2009, 02:15 PM

Can we stop with the "I'm disappointed" and "this is underwhelming" whining already?
If you wanna watch unrealistic fireworks, go watch a Hollywood blockbuster movie or something. LCROSS wasn't done for the awe factor but science returned.

Posted by: centsworth_II Oct 17 2009, 02:38 PM

QUOTE (ugordan @ Oct 17 2009, 09:15 AM) *
Can we stop with the "I'm disappointed" and "this is underwhelming" whining already?

Bravo!
That "underwhelming" image is the first solid indication that LCROSS may meet all it's science goals. What more do you want from a science mission!?

I resisted the temptation to post first after Emily because I wanted to allow time for the naysayers to repent on their own terms. That worked out well. rolleyes.gif

Posted by: Tman Oct 17 2009, 02:53 PM

Right! But they better had involved Hollywood which had added quite a bit explosive to make it clear for the public/audience laugh.gif

Btw. Carry along something like a bomb wouldn't that have been better anyway (in terms of getting better signal/measurements) - unless I'm totally wrong.

Posted by: tanjent Oct 17 2009, 03:18 PM

Quote: "In the coming weeks, the LCROSS team and other observation assets will continue to analyze and verify data collected from the LCROSS impacts. Any new information will undergo the normal scientific review process and will be released as soon as it is available."

I hope this doesn't mean that they will try to sit on any spectroscopic (water / no water) findings until an article has cleared peer review. In the event of a positive finding, I doubt it could be kept secret anyway.

Posted by: Greg Hullender Oct 17 2009, 03:21 PM

In recent years, the big journals have been pretty good about allowing significant results to be announced in advance of publication. When they've got a concrete result, I'm sure they'll announce it.

--Greg

Posted by: elakdawalla Oct 17 2009, 04:04 PM

The first event I'm looking toward where there may be any semi-public discussion of scientific findings will be the next Lunar Exploration and Analysis Group (LEAG) meeting, which is Nov 16-19. All of day 2 (Nov 17) will be devoted to LRO and LCROSS.
http://www.lpi.usra.edu/meetings/leag2009/

--Emily

Posted by: John Copella Oct 17 2009, 08:26 PM

QUOTE
"There is a clear indication of a plume of vapor and fine debris," said Colaprete.


Significant?

Posted by: glennwsmith Oct 17 2009, 08:43 PM

QUOTE
The basic idea is that a disappointment is best handled by acknowledging it as such -- THEN you can wake the morrow morn with some more hopeful thoughts.


The point being that disappointment with the size of the plume does not equate to naysaying regarding the entire mission. I am now as ready as anyone to be pleasantly surprised by the spectroscopic results!

Posted by: elakdawalla Oct 17 2009, 10:14 PM

QUOTE (John Copella @ Oct 17 2009, 01:26 PM) *
Significant?

It just means that stuff is in a gas phase instead of being dust. A vapor of what, is the question.

--Emily

Posted by: siravan Oct 18 2009, 12:28 PM

QUOTE (elakdawalla @ Oct 16 2009, 03:26 PM) *
New data and images released today, but still no word on what the spectrometer detected.


I found the total radiance graph http://www.nasa.gov/394533main_VSP-NSP-total-radiance.png very interesting. It seems that there is a drop in mid IR radiance in the first few seconds after the impact. Water has a very high absorbance in mid IR and I wonder whether this graph has a water signiture. Does anyone know how dust would behave?

Posted by: MarsIsImportant Oct 18 2009, 12:42 PM

error page...page not found. Perhaps it was posted by mistake and quickly taken down.

Edit: or was it just a bad link you posted?

Posted by: SFJCody Oct 18 2009, 12:54 PM

Remove the ) from the end of the URL.



Edit: Corrected now.

Posted by: stevesliva Oct 18 2009, 03:56 PM

QUOTE (centsworth_II @ Oct 17 2009, 10:38 AM) *
That "underwhelming" image is the first solid indication that LCROSS may meet all it's science goals.


BTW, those are these:
Confirm the presence or absence of water ice in a permanently shadowed region on the Moon
Identify the form/state of hydrogen observed by at the lunar poles
Quantify, if present, the amount of water in the lunar regolith, with respect to hydrogen concentrations
Characterize the lunar regolith within a permanently shadowed crater on the Moon

The middle ones do hinge on them not declaring that they chose the wrong spot, and concluding that other spots are different.

Posted by: Zvezdichko Oct 19 2009, 09:32 AM

http://www.roscosmos.ru/NewsDoSele.asp?NEWSID=7818

Translating: The LCROSS failure was predicted even before the start of the mission

Several lunar scientists announced that the failure of LCROSS had been predicted even before the start of the mission. (It's not about a technical failure, but about public disappointment)

New Scientist journal cites scientists who have predicted the unfortunate end of the mission in august 2009. One of them is Peter Schultz. According to him the quantity of the impact ejecta was overemphasized. Peter says that the angle of the plume was calculated incorrectly. It was estimated it would be 45 degrees, but Schultz received a 30-degree result.

Posted by: MahFL Oct 19 2009, 02:49 PM

The camera's imaged the crater right ? but so far it's only a few pixels on the whole field of view. I was under the impression we would see a crater of many many pixels, like we see from LRO, or was that my misconception ?

Posted by: Phil Stooke Oct 19 2009, 04:01 PM

Half way down this page:

http://www.nasa.gov/mission_pages/LCROSS/main/LCROSS_impact_images.html

you can see a 2 m/pixel image of the c. 10 m diameter crater. But it's infrared - we are seeing the warm ejecta, not topography. Remember it's in permanent shadow!

But LRO is attempting to use LROC to get the kind of high resolution images you are thinking of. At this point it's not known if it can get good images in permanent shadow. If it does, it would be imaging using light reflected off surrounding hills. It might take several attempts with different lighting to get anything, if it's possible at all.

Phil

Posted by: marsophile Oct 19 2009, 04:35 PM

QUOTE (Phil Stooke @ Oct 19 2009, 09:01 AM) *
But it's infrared - we are seeing the warm ejecta, not topography. Remember it's in permanent shadow!


Wouldn't the impact flash produce enough visible light to light up a wide area of Cabeus? Or is it the case that the impact spot was so profoundly cold, that it was only heated up to, say, room temperature? Not white-hot, in common terminology? Or maybe the following spacecraft was just unlucky enough that none of the frames coincided with a very short visible flash?

Posted by: nprev Oct 20 2009, 12:19 AM

QUOTE (marsophile @ Oct 19 2009, 08:35 AM) *
Or maybe the following spacecraft was just unlucky enough that none of the frames coincided with a very short visible flash?


That sounds like the safe bet. Doubt that the flash proper lasted more than a few milliseconds at best.

Posted by: marsophile Oct 21 2009, 08:58 PM

http://www.seti.org/csc/lectures

10/21/2009
Special Panel: LCROSS Mission - the first results of the impact

No, they did not divulge the science results, but provided some interesting background information. For example, they made real-time decisions about how to allocate the limited telemetry bandwidth, favoring scientifically valuable spectroscopy over "pretty pictures." Video of the talk is (or will be) available on Youtube.

Posted by: marsophile Oct 22 2009, 09:00 PM

Manned spaceflight reference redacted - ADMIN

Posted by: Sunspot Nov 2 2009, 08:20 PM

Did any UK members watch The Sky at Night last night?

A Special program about LCROSS. While chatting to Patrick back in the UK Chris Lintott seemed to hint, based on his interview with the LCROSS PI, that we might hear some very interesting results quite soon - implying they had detected water.wink.gif wink.gif

Posted by: marsophile Nov 2 2009, 09:01 PM

QUOTE (marsophile @ Oct 21 2009, 01:58 PM) *
10/21/2009
Special Panel: LCROSS Mission - the first results of the impact


The video of that SETI Institute colloquium is now up on youtube:

http://www.youtube.com/setiinstitute

Special Panel Presentation and Discussion with Tony Colaprete, Jennifer Heldmann and Diane Wooden.

Posted by: Sunspot Nov 3 2009, 07:52 AM

QUOTE (Sunspot @ Nov 2 2009, 08:20 PM) *
Did any UK members watch The Sky at Night last night?


Anyone? unsure.gif

Posted by: ngunn Nov 3 2009, 08:24 AM

Yes.

Posted by: Sunspot Nov 3 2009, 08:37 AM

And what did you make of Chris Lintotts's remarks to Patrick? I thought he was making it quite obvious that LCROSS had found water in the plume/ejecta.

Posted by: ngunn Nov 3 2009, 08:54 AM

You may be right but I didn't draw that inference whilst watching it. I assumed the programme was recorded a while ago.

Posted by: Sunspot Nov 3 2009, 09:05 AM

QUOTE (ngunn @ Nov 3 2009, 08:54 AM) *
You may be right but I didn't draw that inference whilst watching it. I assumed the programme was recorded a while ago.


LOL How could you not have... he all but said they had found it lol. wink.gif wink.gif

Posted by: marsophile Nov 3 2009, 10:42 PM

http://www.skyandtelescope.com/news/68841092.html

Some hint of a result from LRO observation of the impact site.

Posted by: djellison Nov 3 2009, 11:12 PM

QUOTE (Sunspot @ Nov 3 2009, 09:05 AM) *
LOL How could you not have... he all but said they had found it lol. wink.gif wink.gif


No he didn't. He said the PI seemed to have a smile on his face that suggested he might be happier with the results than he was letting on. Having watched it - I went back and looked at him, and he just looked kind of smug to be honest.

Posted by: Zvezdichko Nov 6 2009, 11:33 AM

QUOTE (marsophile @ Nov 3 2009, 11:42 PM) *
http://www.skyandtelescope.com/news/68841092.html

Some hint of a result from LRO observation of the impact site.


So LRO didn't see evidence of water. This is probably going to be classified as a dry impact after all.

Magnesium and mercury? Intriguing, but not what we expected.

Posted by: Sunspot Sep 13 2010, 10:40 PM

Although they didn't show any trace of the impact, are the Hubble observations of the impact site likely to make into the PDS?

Posted by: ugordan Sep 13 2010, 10:49 PM

Hubble data isn't archived at the PDS since its main purpose isn't planetary science. The data can be accessed http://archive.eso.org/archive/hst/search/#Q-S+R-+D- among other places. The LCROSS impact observations are already there. Judging by the preview images, there's nothing to see from the imaging standpoint.

Posted by: Sunspot Sep 13 2010, 10:53 PM

Just wondering what the limb of the Moon looked like from Hubble

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