Celestia Forums

Holy mackerel...

The picture is pretty but read this

HiRISE took this first test image from orbit on March 24, 2006, from an altitude of 2,489 kilometers (1,547 miles), achieving a resolution of 2.49 meters (98 inches) per pixel, or picture element. The smallest objects of discernable shape are about three pixels across. An image acquired at this latitude during the Mars Reconnaissance Orbiter's main science phase, beginning in fall 2006, would be taken from an altitude of about 280 kilometers (174 miles) and
have a resolution of 28 centimeters (11 inches) per pixel.

Now THAT is high resolution.

On its own, that sort of high resolution would be pretty useless... fortunately they seem to be taking lots of context images to make it useful . (there's a link to one on that page too).

Looks promising. BTW, anyone else encountering the old 'craters look like hills' problem on the context image? A lot of people seem to have that problem with Mars, for some reason.

Malenfant wrote:On its own, that sort of high resolution would be pretty useless...

How so?

- Hank

Well, for one, without the context images it would be pretty difficult putting such high resolution images in place. It would be like those old Discover Magazine puzzles, where they show a high macro shot of something, and you're supposed to figure out what object they are (the baseball was always easy for me). But in this case, you'd have to figure out what type of terrain, the surrounding geology, probably even what region the image was taken in.

*With* the context image, of course, none of that is a problem, and what you have is essentially an orbiter that can perform observations on par with a rover, minus any sort of hands on testing of course.

...John...

What Dollan said. I remember during the early part of the Galileo mission we had a lot of high resolution images of Ganymede and nobody knew what the heck we were looking at. It was only when we got context images later on to put it all in er, context that it started to make sense...

Plus, I wonder at the utility of having something that can resolve things about the size of a 17" computer monitor on the surface of another planet. "Oh look, another boulder! And there's a large rock! And another one!"

Well, I will be looking forward at looking at some of these "flows", or whatever they are, that have been images along crater walls. I'm sure that there are many other wonderful aspects.

For myself, I would love to be able to see some of the older landers in high detail, just to see what shape they're in. Highlights would be the Vikings, of course, but I'd also love to see some of the sites where the failed Soviet landers touched down, crashed, etc. Not that I think we can simply point and click. I'm sure there are degrees of uncertainty that equal many kilometers...!

...John...

Dollan wrote:For myself, I would love to be able to see some of the older landers in high detail, just to see what shape they're in. Highlights would be the Vikings, of course, but I'd also love to see some of the sites where the failed Soviet landers touched down, crashed, etc. Not that I think we can simply point and click. I'm sure there are degrees of uncertainty that equal many kilometers...!

...John...

Well, one would hope those degrees of uncertainty are in the locations of the landers, not of the camera pointing!

I'm not sure how well it'd be able to see a Viking Lander. It'd be what, about 5x2 pixels wide at most if the resolution is 30cm/pxl? Might see its shadow if the lighting is right too. But would won't see much detail on it.

Plus don't forget, there's been about 30 years of wind and dust blowing in to fill the holes and cover up the debris from the crashlandings...

Imagine the 28 cm per pixel in the Blue Marble Next Next Next Next ... Generation

You will can see people in earth in Celestia

Malenfant wrote:What Dollan said. I remember during the early part of the Galileo mission we had a lot of high resolution images of Ganymede and nobody knew what the heck we were looking at. It was only when we got context images later on to put it all in er, context that it started to make sense...

Don't we already have a lot of high resolution images of Mars from previous orbiters (covering virtually the entire planet) which provide context?

Malenfant wrote:Plus, I wonder at the utility of having something that can resolve things about the size of a 17" computer monitor on the surface of another planet. "Oh look, another boulder! And there's a large rock! And another one!" ;)

Do you also doubt the utility of images from surface landers?

- Hank

hank wrote:Don't we already have a lot of high resolution images of Mars from previous orbiters (covering virtually the entire planet) which provide context?

NOt sure how coherent that coverage is. I know MGS' hires images were rather scattershot in nature.

Do you also doubt the utility of images from surface landers?

Not really. Landers are a different beast - they can usually get in there and poke at the rock (and in the case of the rovers, can actually move around too). Plus they provide cool looking panoramic views .

I just think there's diminishing returns if using an orbiter to take ridiculously high resolution images of the surface. To me, an 800x800 image showing a closeup of part of a single sand-dune with 12 large chunks of rock scattered on it is a whole lot less useful than an 800x800 image showing the whole sand field. You can get a lot more information about the regional geology out of the lower resolution image, whereas the closeup just tells you that there's rocks on a dune.

Mal,

Perhaps you've overlooked one of the reasons for getting extreme resolution pictures of the surface: they need to pick a landing spot for the manned Mars expedition. The first Moon landing was very close to being a disaster because of all the large rocks that were in the way.

selden wrote:Mal,

Perhaps you've overlooked one of the reasons for getting extreme resolution pictures of the surface: they need to pick a landing spot for the manned Mars expedition. The first Moon landing was very close to being a disaster because of all the large rocks that were in the way.

I guess... manned Mars landings aren't even remotely on my radar. And I'm highly skeptical that it'd ever happen anyway - as soon as the current US administration is over I'm pretty confident that the next administration will can it.

Well, Frankly, despite what the current administration says, and despite what a lot of people think, Bush's announcement was *not* even remotely similar to Kennedy's annoucement about going to the Moon. Indeed, the political climate now is so totally different, that if Kennedy today were to make his announcement about going to the Moon, I doubt that it would get much past the discussion phase. We're in no hurry to go to Mars, or even back to the Moon for that matter. Competition to do so is really pretty much gone; in short, we've been there, done that, if China or India want to go, more power to them!

Back to the MRO, though, it should be noted that the images that will be returned won't simply be a square only a few inches across. There *will* be accompanying context images, from the other orbiters and the MRO itself. It isn't limited to images of that resolution. And those absurdly high resolution pics will have tons of usage; we'll be doing more useful geological exploration of Mars with those images than we ever have before. Sure, we won't be able to root around and take direct chemical readings of the rocks, but pictures *can be* worth a thousand words... and I don't think the MRO cameras are limited to visual wavelengths (though I could be wrong on that one).

Also, while manned landings might be a prospect for a few decades down the road, other unmanned landers will certainly be in the pipeline, and finding a safe place for them to land will be every much as important as finding one for a manned crew.

...John...

The MRO's science instruments are described at http://mpfwww.jpl.nasa.gov/mro/mission/sc_instru.html
There are three cameras in addition to a spectrometer, radiometer, shallow radar, and accelerometers.

Hi all,

I did a quick can of this thread so I may have miissed some of it but has anyone used this software called ISIS. It's supposed to put together the images from a mission and a mosaic can be created. With ISIS one could download raw data and create one's own texture with whatever coordinates one wants. I'm not sure if MRO data is available yet but there is a lot of data from Odessey, Clemintine, Voyagers, Gallileo, etc..

I just started to try this and it will take time to learn but the benifits seem to be well worth it.

ISIS can be found in the software section of the Themis page from ASU.

http://themis.asu.edu/

cartrite

cartrite wrote:Hi all,

I did a quick can of this thread so I may have miissed some of it but has anyone used this software called ISIS. It's supposed to put together the images from a mission and a mosaic can be created. With ISIS one could download raw data and create one's own texture with whatever coordinates one wants. I'm not sure if MRO data is available yet but there is a lot of data from Odessey, Clemintine, Voyagers, Gallileo, etc..

I just started to try this and it will take time to learn but the benifits seem to be well worth it.

I used it a lot when I did my PhD... it's pretty complicated stuff. It's fairly impractical for doing a full global textures, but it works nice for stitching together images of small areas of the planet. But you have to get your head around how the pointing data works (usually very badly, the pointing is often way off) and how that relates to the way images are projected. Good luck if you want to match images, unless you have IDL (a horribly expensive mathematical programming development thing) then you have to MANUALLY match images together to make a mosaic if the pointing is off... Ugh. I could go on but it'd only bring back more painful memories of spending hours and hours (if not days and weeks) poring over images of Ganymede and finding match points and entering those into mosaic scripts... Plus of course you won't have colour images unless you process all the images involved in the RGB image.

Maybe they've improved it a bit since I used ISIS but when I was using it, it was a right nightmare to get working properly...

Malenfant,

So far I've just downloaded Isis 3 and been doing the workshops which don't seem that bad.
Kinda like Image Magik. The difficulty factor seems relative to where you start. If you use level 0 data and are starting from scratch there seems to be a lot of work. But running some correction routines on level 1 or level 2 data to remove noise, etc. seems a little better. As far as IDL They have something called IDL DLM which I haven't got to work yet. They also have Qview which gives an idea of what was done. I do conversions to png or tif and inspect the image with the gimp. Anyhow a long way to go.

I do agree that the primary uses will be small areas. A way of creating a texture for a high resoloution 3d model or close up VT's.

I also read some news on Gimp 3.8(beta) which seems to have PDS format capabilities now. That may be worth downloading and trying out.

Edit: After rereading the Gimp news I saw there was no PDS format capabilities. I missread it the first time.
Sorry

Anyhow, I'm not going to quit my dayjob

cartrite

RVS wrote:HiRISE acquired two dramatic views of the Martian moon, Phobos, on 23 March 2008.

Stunning!

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