Busy preparing a new Outreach talk here, and have been trying to find some images to illustrate the "power" of HiRISE for a non-technical audience. Playing about with - sorry, carefully looking at the images on - the addictive Mars Global Data site I found a cute landslide on Xanthe Terra that does the trick nicely. Using the IAS Viewer you can zoom in on the boulders carried down the slope by the landslide and even see cracks and splits in them... unbelievable...!

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Anyone else got any fave examples?

Emily's series about White Rock is good, too.

(Course now that I go looking, it might not have gotten to HiRise!)
http://www.planetary.org/blog/archive/35/

I did -- but you remind me I promised to wrap this up, and I haven't delivered on that promise yet...
http://www.planetary.org/blog/article/00001419/

--Emily

Yep, Emily's "White Rock" sequence is an outstanding piece of work, to be sure. I'm not comparing this Xanthe sequence to it at all; I was just struck by the detail visible in those shattered rocks

As in Emily's presentation, consider adding scale bars to the images?

Spider:
http://hirise.lpl.arizona.edu/PSP_003087_0930

The famous avalanche:
http://hirise.lpl.arizona.edu/PSP_007338_2640

Rolling stones:
http://hirise.lpl.arizona.edu/images/2008/...47_1895_cut.jpg

Frost covered gullies:
http://hirise.lpl.arizona.edu/PSP_001552_1410

I've not seen the image on the right before - I make that an Evel Knieval-like ~17m jump across the crater. Imagine being sat in the bottom of that as a 4m rock zips over your head...

Andy

I found another unusual boulder track. You can see clearly how increased speed of the boulder on the slope. Jumps were increasingly longer, even a few dozen meters.

Hills Northeast of Mojave Crater (PSP_008430_1895) - general view
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Hills Northeast of Mojave Crater (PSP_008430_1895) - "Rolling Stone"
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Boulder in the final position
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I was very skeptical before Mars Reconnaissance Orbiter mission. Another mission to Mars similar to the Mars Global Surveyor mission, what's interesting in this. I was wrong, MRO is the ultimate achievement in the field of imaging of Mars from orbit.

Judging from the freshness of the tracks, this event must have happened quite recently. Did MRO by any chance image this area before?

Yes, Absolutely. MRO almost "feels" more like viewing the martian landscape out of a helicopter window than from orbit ...

When I was younger I have always been dreaming about future Mars missions involving balloons or airplanes and wondered how phantastic a feeling it would be to view all the images and vistas those aircrafts would take from above ... finally bridging the gap in scale between the ground level images of the landers (Viking) and the very low resolution views of the orbiters ... Now we don't have martian airplanes yet but we have MRO ... and it's even better for it's global scope of operation

I would love to see an anaglyph of that scene!

Interesting thought. Is there a way to calculate at what altitude a human (eye) has the same resolution as HiRise? Is it comparable to a helicopter flight or looking down through the clouds from an airliner?

Assuming that the human eye visual acuity is about 0.59 arc min and HiRISE at 0.25m/pixel you get an altitude of about 1456m or about 4800' (if I did my math correctly).

Paolo

What's circa the size of that boulder? 3x4 meters?

There was some concern before that HiRise's resolution would actually be greater than the Mars atmosphere would allow due to twinkling. Has anyone taken a look at that again? What's the new maximum theoretical resolution from orbit? Less than 5cm?

I don't know the exact numbers but from looking at many hundreds of HiRise image it does "feel" like the highest resolution level indeed lacks some of the "crispness" of the larger scale zoom levels ... don't know if this is due to atmosphere twinkling or other optical and/or image processing effects though ....

The camera developed a fault not long after science operations began. There has been an obvious deterioration in image quality as a result - images are much grainier and not as crisp.

Look at this first picture obtained of Spirit at Home Plate

The reported degradation of the camera has been found to be minimum in past discussions; see, for example:


and


Steve M

Hey, look... HiRISE is on Twitter now, too...

http://twitter.com/HiRISE

A picture is worth 140 characters!

Just... beautiful...

Capri Chasma images

Many of the recent images are very noisy indeed. Others however, are still very good. This image of Gusev was taken just three months ago.
http://hirise.lpl.arizona.edu/PSP_010097_1655

AFAIR the noise problem was present only in some of the CCDs in Hirise's CCD array. Also the problem was remedied somewhat by warming(?) the CCDs.

I think the atmospheric conditions on Mars play a bigger role. That could be seen in some of the images taken during the major dust storm around rovers' regions.

Inbetween writing Christmas cards and eating mince pies today I've been playing about with the wonderfully addictive website http://global-data.mars.asu.edu that lets you explore Mars through the eyes of spaceprobes from Viking to MRO. I like just dipping in at random, playing a kind of "martian lucky dip" if you like, and seeing what turns up. I just found something interesting... well, I think it is.

Image http://hirise.lpl.arizona.edu/PSP_005665_1800 is entitled "Change detection in Dark spot", so I thought it was worth a look... change is always a good thing on Mars, after all... into IAS Viewer and fine, looked just like one of those "fresh impact craters" to me - a dark "splash" of colour on a bright background. Zoom - and yep, right in the centre there's a small cluster of craters. But that's not what caught my eye - what made me go "hmmm" were the many dark lines and trails coming off the terrain around it. There are hundreds of them! I'm just puzzled what I'm seeing... this isn't a polar area, so the light terrain can't be frost- or snow-covered, yet it looks like something is coming out from underneath a surface layer..?

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Anyway, just thought it was interesting - note: not odd, interesting! - and wondered if anyone has any thoughts about it.

HiRISE. What a fantastic camera!

Stu, do those lines appear throughout the region or just in the immediate proximity to the new craters?

Best to take a look yourself Dan... they're more common close to the craters I think, but not exclusive to the immediate area.

They look like ordinary dry dust avanches.

Fascinating, good catch, I'm looking forward to finding out what on Mars it is...

Edit: OWW - thanks!

Exactly what I thought... wasn't suggesting anything else... just thought it was an interesting area and thought others might think so, too. Still a bit puzzled by the process tho... there are an awful lot of them, and they do look like they're coming from beneath a surface layer of some kind, to my eye at least. But I'm no geologist, obviously.

Me neither.
But I don't see any layers. To me, it looks like they all begin at the top of the 'plateaus'.

Hmmm, you may be right. I'm just very impressed with the area in general.

Easily impressed huh? Dust, dust and... more dust.
To me this terrain looks much more diverse, interesting and....beautiful:
http://hirise.lpl.arizona.edu/PSP_009537_2045

Follow that riverbed at 50% zoom and be amazed.

And one weird crater:
http://hirise.lpl.arizona.edu/PSP_009320_2150

I'm impressed by the thought of all that dust sliding down those slopes, yeah, cos I can imagine being there and seeing, what, dozens of avalanches of dark dust and stones hissing and slithering down the sides of the ridges or plateaus or whatever they are all around me, triggered by - what? Gentle rumblings in the rocks beneath the mighty volcanos that lie to the east? A tremor running through ground after a faraway impact?

Sometimes it's what you can't see that makes a martian landscape magical.

Love your weirdy crater tho - present for you

OWW's Crater

Then you're gonna Love this one:
http://hirise.lpl.arizona.edu/PSP_004390_1035

Here's another strange crater.... I THINK it was a crater once.
http://hirise.lpl.arizona.edu/PSP_010206_1975

There are some coarse layers (red lines in the attached image) in the underlying material (Medusae Fossae Formation according to the Geologic Map of the Western Equatorial Region) and some hints of fine-scale layering (see arrows). But these layers are apparently not the sources for the dust. It could be created by surficial weathering of the layered rocks, consistent with the observed sources near the top of slopes.

The Face that was Erased. Hoaxland will have a field day.

Couple of new shots here...

More HiRISE highlights

Dancing with the stars!
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full inline quote removed - mod

Wow: the perfect shot

(and the perfect title, centworth II

The noise in HiRISE images was almost completely eliminated by warming up the CCDs prior to use, the only exception was that IR 10-1 is still a bit noisy, which was the worst of the CCDs. I think they might have even gotten rid of that one too, but it's been a while since I've checked...

HiRISE zooms in on Pavonis...

http://cumbriansky.wordpress.com/2009/04/2...s-in-on-pavonis

... and another "volcanic treat" from HiRISE...

http://cumbriansky.wordpress.com/2009/04/2...-volcanic-treat

Love that camera!

Stu, I hope you don't mind me posting this link here (since you haven't yet). I found it fascinating. Your impact sites seem to be arranged in a nice 'landing ellipse'! Several questions come to mind. Is the group statistically significant in terms of spatial and temporal density such that a common origin is a serious possibility? Is the 'landing ellipse' consistent with an atmospheric break-up, or is it too big? Folks here can shed light I'm sure.
http://cumbriansky.wordpress.com/2009/05/0...or-a-mars-base/

Shooting from the hip here, Stu's impact cluster (great find & great article, BTW, dude! ) covers a very large amount of surface area, so I wouldn't expect them to originate from the atmospheric breakup of a single object. Mars' atmosphere is super-thin anyhow, and nowhere is it thinner than in the Tharsis Bulge area.

However, one interesting possibility is that this is what's left of the impact of five or more discrete objects that were once one, but were disrupted while still in space into a loose association separated by tens of km or more. Perhaps a small comet nucleus that had been fragmented after perihelion passage then had the misfortune to encounter Mars on the outbound leg?

</wild speculation mode>

Thanks guys, glad you found the post interesting. It's probably just a coincidence that those "fresh craters" are all in the same area (roughly), but hey, you never know. I just thought it was an interesting find. Man, I love HiRISE!

Very very very cool pic of Victoria Crater released today... oblique view...

http://hirise.lpl.arizona.edu/ESP_013954_1780

Oppy's tracks stand out really clearly on it, too...

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Nice! And here's the intrepid rover itself.

Phil

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A comparison between the two HiRise images of Victoria Crater.
I've taken the original view and have oriented and distorted it to a similar perspective as the latest version.

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Colourised crops from image of gullies in Gale Crater, released today...

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The absence of any impact features at any scale here is just amazing.