Rosetta's Earth Swing-by, 13th November, 2007 Options

[ustrax]

"Yesterday, 18 October at 18:06 CEST, the thrusters of ESA’s comet chaser, Rosetta, were fired in a planned, 42-second trajectory correction manoeuvre designed to 'fine tune' the spacecraft's approach to Earth. Rosetta is now approaching Earth for its second planetary swing-by of 2007."

From here.

Maybe it is time to start a new thread...
Get out of the way, Rosetta is coming to visit us at full speed!

[ugordan]

Cool. I can't wait to NOT get more great images from Rosetta...

[ustrax]

Cool. I can't wait to NOT get more great images from Rosetta...

Oh yes...I forgot that a complaineorit shower takes place around each Rosetta Swing-by...

[jamescanvin]

Wow! Maybe I missed it - But I hadn't seen the stunning Philae image of Mars+Rosetta before!

[ustrax]

Wow! Maybe I missed it - But I hadn't seen the stunning Philae image of Mars+Rosetta before!

I presume you were taking vacations at Saturn by then...

[jamescanvin]

Well, New Zealand - similar but with fewer rings.

I've found that thread now so i can catch up - silly me thinking that that there wouldn't be any images from the flyby yet, being that it's still the same year. #

[CAP-Team]

Isn't Rosetta the first spacecraft to visit Mars and then Earth again?

[ugordan]

Isn't Rosetta the first spacecraft to visit Mars and then Earth again?

I believe it is.

[elakdawalla]

I don't know what their release plans are but they do at least plan to take some good photos. I asked Gerhard Schwehm and he said that he'd get back to me with specifics, but broadly speaking, "OSIRIS will observe at approach briefly the night side of the Earth and after perigee will make observations of the Earth and the Moon under the more favourable lighting conditions having the Sun in the back."

--Emily

[tedstryk]

Does anyone know anything about the geometry of the lunar imaging? I recall that it will be fairly distant, but I am not sure if it is near side or far side.

[CAP-Team]

Closest approach is on 14 november 2007 at about 0:00 GMT (381,000 km)

Approach is on the unlit side of the moon which is the side that faces earth, after the closest approach we're looking at the trailing hemisphere.

[climber]

Well, New Zealand - similar but with fewer rings.

Unlike Rosetta's I guess your pictures were... All... Black...

[IM4]

Here goes!

1) Science plans for Rosetta’s Earth flyby :
http://www.planetary.org/blog/article/00001216/

2) Yet another illustrations to the article above - groundtrack and simulated views :

[Holder of the Tw...]

Please note that the Minor Planet Center's official designation for Rosetta is asteroid 2007 VN84

2007 VN84

Editorial Notice

[elakdawalla]

Funny! Thanks for pointing that out.

--Emily

[gndonald]

Please note that the Minor Planet Center's official designation for Rosetta is asteroid 2007 VN84

2007 VN84

Editorial Notice

This'll be the third time that this has occurred. There was 'J002E3 that turned out to be the S-IVb from Apollo 12 back in '02. Before that the satellite WIND was marked down as a potential Earth impact threat, at least until it used its RCS system to change orbit.

[Paolo]

This'll be the third time that this has occurred. There was 'J002E3 that turned out to be the S-IVb from Apollo 12 back in '02.

I am not sure, but I don't think that the identification of J002E3 with the Apollo 12 stage was 100 per cent sure.

[djellison]

They did some spectroscopy and identified it as TiO2 - the constituent of the white paint used on the those LV's.

Doug

[nprev]

Good grief...that's hysterical! Seems as if our NEO searches are more than effective, anyhow...

[cndwrld]

Rosetta Blogging
I hadn't seen this before, so I thought I'd post it. ESA has a blog going for the Rosetta Earth Swing-By 2 (ESB2), at
http://webservices.esa.int/page.php?id=37819

It mentions the coverage at the SpaceEurope and Planetary Society blogs.

[cndwrld]

ESB2 Info

From the Rosetta Earth Swing-By 2 Master Science Plan-

"The baseline attitude of Rosetta is GSEP (GyroStellar Ephemeris Phase, a S/C guidance mode using gyros and star trackers for attitude control) with the spacecraft +X axis pointing to the Sun with a possible bias.

The closest approach (CA) will take place on November 13 (DOY317). At the moment of closest approach, the altitude of
Rosetta will be 5330 km above the Earth surface, at sub-surface position: 63°46' S, 74°35' W (local time 16:17)."

The primary purpose of the Earth Fly-By is trajectory adjustment and velocity change, not science. Science only gets done to the extent that it doesn't interfere with anything else.

The attitude that the spacecraft can be in depends on upon allowed exposures of certain faces to the Sun, limited to certain amounts of time. The allowed attitudes effect what the instruments can see. And the instruments are optimized for slowly revolving around a comet at 4 AU, not the brightly lit crescent of a planet during a rapid fly-by. The science value of any observations are therefore not great, but it does provide an indirect science value by allowing instrument calibrations. It might also generate a few really cool pictures. This may not be scientific, but it is still cool.

[jamescanvin]

Please note that the Minor Planet Center's official designation for Rosetta is asteroid 2007 VN84

Picked up a copy of this mornings Metro on my way back from London and got quite a shock when I turned the page and saw a big picture of Rosetta with a headline along the lines of 'We Missed Up'. I had a few moments of worry until I realized they had just picked up on this story and there hadn't been some major targeting error or something. Phew!

James

[Guest_PhilCo126_*]

Well, this time Earth's flyby is the most important part of the billiard orbital path
Does anyone has an updated orbital path image please ?

[Guest_PhilCo126_*]

The above image dates from 5 years ago, so I'm searching the new version but even the ESA.int multimedia website only has a low resolution version

[BrianJ]

Does anyone has an updated orbital path image please ?

I think this is more recent....

[Guest_PhilCo126_*]

Indeed Brian, I just got that trajectory-schedule in my e-mail via Dr Andrea Accomazzo, who promised me to check for the color version

[ustrax]

Do you guys the orbit view tool at Rosetta's Science & Technology site? Quite useful...
It's on the left column.

[Guest_PhilCo126_*]

Are they serious?
Rosetta mistaken for a near-miss asteroid !

http://www.space.com/businesstechnology/07...id-mistake.html

[centsworth_II]

Are they serious?

See post #14 of this thread. Once again, you heard it first on UMSF.com!

[Del Palmer]

Flyby successful!

http://webservices.esa.int/page.php

[jamescanvin]

First images (greyscale nav-cams) are up.

http://esamultimedia.esa.int/multimedia/es..._cam/index.html

James

[ustrax]

Images are coming IN!

EDITED: You beat me to it James...

[jamescanvin]

While we are waiting, here is a slightly improved version of the two Graham Land images.



Some kind of ice planet...

[Stu]

If you zoom in on that you can just make out some AT-ATs closing in on the Rebel base...

[tedstryk]

First images (greyscale nav-cams) are up.

Who would have guessed that 2007 VN84 has cameras and can transmit them? What a cool asteroid!

[tuvas]

Who would have guessed that 2007 VN84 has cameras and can transmit them? What a cool asteroid!

In case you didn't see it, http://www.space.com/businesstechnology/07...id-mistake.html

[ugordan]

In case you didn't see it, http://www.space.com/businesstechnology/07...id-mistake.html

I'm pretty sure he's aware of that.

[Stu]

First OSIRIS images are up...

[ugordan]

Looks like they forgot to link to full-res images.

I wonder if they took a RGB set of the night lights. Probably not, but it would be very cool to see the actual color of the lights as well as the crescent limb.

[djellison]

I think they learnt the lesson after the Mars flyby - From me wandering around ESOC going "Any Wifi? I want to blog for the enthusiasts!" to this brilliant inside story in near real time. Much credit to the guys in Darmstadt!


Doug

[ugordan]

The blog idea is commendable, I was actually surprised when I first learned they were going to do it. I hope they continue this practice in the future as well.

EDIT: Higher resolution OSIRIS image versions are here. Guess what my next wallpaper is...

[volcanopele]

<Geography nerd mode on>
Very cool images, but the feature they label as Bagdad (sic) is actually Tehran
</Geography nerd mode off>

[ngunn]

the feature they label as Bagdad (sic) is actually Tehran

Oops - have you informed the President?

[Paolo]

And it looks like their Windows does not know Hongkong...

[ugordan]

Just for fun...

[Guest_John Flushing_*]

Rosetta beams back Earth photos after flyby.

[jamescanvin]

A composite of the OSIRIS crescent and night lights image has been posted.

http://webservices.esa.int/page.php?id=37994



Click image for full size version.

[ugordan]

The Moon and Europe - Rosetta OSIRIS images

[edstrick]

I played with the Earth-crescent image to see how much detail is present in it... Here's a before and after some bandpass filtering.

Attached thumbnail(s)

 

[Stu]

Nice one Ed!

For anyone interested there's a new poem up here, inspired by the fly-past...

[nprev]

"Mars’ shifting cinnamon sands shone

lantern-bright in the endless empty night

that has become my life

and through my outstretched solar wings

I caught a fleeting glimpse of proud Olympus,

a cloudy scarf of cirrus wrapped around its lofty peak."



VERY nice, Stu; one of your best works in my estimation, FWIW. The voyage is real, epic...properly documented in terms of its nobility and vast traverses by you.

[Stu]

Thanks for the great review! Glad you like it, I was quite pleased with how it turned out. Looks like ESA were too, they've very kindly put it up on the Rosetta blog which I'm v chuffed about.

[Stu]

Rosetta sees Earth...




Beautiful, just beautiful...

[djellison]

I don't know if the ESOC team and the OSIRIS guys heard what we were saying after the Mars flyby - but they have just turned things around in 9 months. The blog, the kodak moment images - I'm proud of my space agency right now, and that's a fairly unique thing for a European.

Maybe Uwe heard us Stu?

Doug

[volcanopele]

Here is the image with north up and east to the right:

Attached thumbnail(s)

 

[Stu]

I don't know if the ESOC team and the OSIRIS guys heard what we were saying after the Mars flyby - but they have just turned things around in 9 months. The blog, the kodak moment images - I'm proud of my space agency right now, and that's a fairly unique thing for a European.

Maybe Uwe heard us Stu?

Doug

Well, maybe he heard you! I think I was just a fly buzzing "Where's that Mars crescent image you promised us?!?!" annoyingly in his ear!

But seriously, yes, I know what you mean, it's a remarkable and wonderful turnaround as far as Outreach and image release is concerned. The blog was nothing short of superb, a textbook example of how to keep enthusiasts informed about and involved in a mission as something exciting happened. The enthusiasm of all the people involved really shone through in the blog entries, you could tell they were genuinely excited about the fly-past themselves, and took time to answer questions as they came in. The day afterthe fly-past I exchanged emails with Daniel Scuka and he was delighted with how things had gone, and said they intend to repeat the blogging for other missions and ESA activities (he mentioned the delivery of Columbus), which has to be a good thing.

I still think that ESA has some way to go. There's been so little data released from it that VENUS EXPRESS is a forgotten or invisible spaceprobe as far as the public are concerned, and I still feel like we're being handed MARS EXPRESS images as treats now and again, and yes, the continuing absence of that "crescent Mars" image still bugs the hell out of me personally because of the principle of the thing, but that's my problem, I know. But last week's ROSETTA fly-past has shown there's a real potential for ESA to "work" when it comes to Outreach and PR, and yes, I'm very proud of them too right now. More than that, when I give my talks in the run-up to Christmas I'll be able to show people breathtaking images of the Earth as seen by a European spaceprobe, and look them in the eye and say "You helped pay for those images to be taken", which is very, very cool

[mchan]

From the other side of the pond, I give ESA "two thumbs up" for its Outreach shown in the Earth fly-by blog.

[ugordan]

Very cool image, but I get the feeling they forgot to account for nonlinearity of the computer screens. While CCD-based scientific cameras typically produce linear digital numbers, CRT screens have a nonlinear curve (gamma). This has the combined result of enhancing contrast when viewing space images on computer (or TV screens). This effect is also present in MESSENGER Earth flyby imagery. I've applied a (CRT display correct) 2.2 gamma to the image in an attempt to make the displayed brightness better resemble what was actually seen by the camera:



This brings the overall contrast to a similar level of the Kaguya Earth-set imagery, which, being an HDTV camera probably accounts for this nonlinearity by default. A bit of Asia also shows up better with 2.2 gamma.

EDIT: A slight tweak to the blue channel because the gamma increased the brightness of the background in blue channel.

[Pertinax]

What what was the time and date for the full earth image? I am having a harder time than I expected in finding that little bit of trivia!

Also, isn't that TC SIDR moving into Bangladesh? I don't remember any previous full earth (non-geostationary) images containing a fully developed tropical cyclone, particularly not one that was as significant as Sidr, nor essentially at what looks to be very near the time of landfall.


-- Pertinax

[helvick]

Good catch - I'm pretty sure that you are correct that should be Sidr in the upper right of the image but I think this was a day or two before landfall. It's still a very significant image and ugordan's tuning has substantially improved the detail in my opinion.

[tedstryk]

Very cool image, but I get the feeling they forgot to account for nonlinearity of the computer screens.

Depends. The problem with compensating for the nonlinearity of a monitor is that it really washes out low contrast features. In reality the image has a far wider dynamic range than can be shown on a computer monitor, and Earth, with its dark oceans, somewhat brighter land, and really bright clouds really strains this. What I am saying is that it may not be accidental. It is a trade-off. One can compress the dynamic range on a monitor in a linear way and better replicate the relative brightness of things, or one can privilege the more interesting parts of the dynamic range and preserve low contrast details.

[ugordan]

One can compress the dynamic range on a monitor in a linear way and better replicate the relative brightness of things, or one can privilege the more interesting parts of the dynamic range and preserve low contrast details.

I was going for the former in this case. There's something about Earth that makes me want to see it appear as close as possible to what it would actually look like to human eyes, rather than doing any (in)advertent contrast enhancements. This is unlike oher objects like icy moons where the contrast is low and makes them look dull. This is our homeworld. You can compare low Earth orbit views taken by astronauts with ordinary cameras and see that they most of the time differ in contrast to these distant shots by space probes.

Of course, in the end computer screens still fail to visualize the sheer brightness of Earth in the blackness of space - it was often said to be painfully bright by Apollo astronauts as the eye had trouble adapting to a pitch black void and bright cloudtops at the same time.

Here's a fun comparison between Kaguya and Rosetta, processed to have a similar resolution and sharpness as Kaguya's shot (click to enlarge):

[Pertinax]

...but I think this was a day or two before landfall.

I agree. The more I looked at the image I realized as well that it had to have been a day or two earlier than I first though.

-- Pertinax

[ugordan]

LOL! Am I really the first one to realize the Rosetta shot is actually mirrored left-right?
Here's the correct view:



I knew there was something funny looking about that Australia

Here's proof:

[volcanopele]

Here is the image with north up and east to the right:

I did

[ugordan]

I did

Oh, my bad. I thought you just rotated it so north is up. I said to myself "where else would east be?"

Someone ought to let the Rosetta team know, though..