Spirit's Landing Site Awash in Green?

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

The same area was acquired by Odyssey in this false color image:
http://themis-data.asu.edu/img/V03415003_C321.html

Don Davis is an independent space artist / researcher who has processed
color images for Malin in the past. Here is his processing of the Gusev
landing site into "true color" from Odyssey data
http://www.donaldedavis.com/BIGPUB/DD_V03415003.jpg

What are your comments on this?

--
James Burk
MarsNews.com

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

Remember the Mars Express color camera is not true color. It is a four
color camera with wavelengths peaked at 440, 530, 750, and 970. These
are blue, green, and two near-IR.

The human eye has peaks at 450, 540, and 580 for blue, green, and red
respectively. Note that green and red are very close together.

When they take full spectrum images with Spirit, they use 11 different
filters centered at 430, 480, 530, 600, 670, 750, 800, 860, 900, 930,
and 980 nm. They have taken a few pictures with the whole spectrum and
they are probably the best representation of the color of Gusev
crater.

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

Remember the Mars Express color camera is not true color. It is a four
color camera with wavelengths peaked at 440, 530, 750, and 970. These
are blue, green, and two near-IR.

The human eye has peaks at 450, 540, and 580 for blue, green, and red
respectively. Note that green and red are very close together.

When they take full spectrum images with Spirit, they use 11 different
filters centered at 430, 480, 530, 600, 670, 750, 800, 860, 900, 930,
and 980 nm. They have taken a few pictures with the whole spectrum and
they are probably the best representation of the color of Gusev
crater.

James Burk wrote:

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

This has already been discussed here to some extent. See the recent
"Gusev crater looks mouldy!" thread. Personally, I think the ME colors
are way off. I suspect that they are not intended to be approximate
true color. The dark regions are darker soils, which seems to be the
reason for the low albedo areas at all scales, including the dark
regions we see in the telescope. At the scope they don't look green...

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

SkyTools Software for the Observer:
http://www.skyhound.com/cs.html

Skyhound Observing Pages:
http://www.skyhound.com/sh/skyhound.html

To reply remove spleen

James Burk wrote:

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

This has already been discussed here to some extent. See the recent
"Gusev crater looks mouldy!" thread. Personally, I think the ME colors
are way off. I suspect that they are not intended to be approximate
true color. The dark regions are darker soils, which seems to be the
reason for the low albedo areas at all scales, including the dark
regions we see in the telescope. At the scope they don't look green...

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

SkyTools Software for the Observer:
http://www.skyhound.com/cs.html

Skyhound Observing Pages:
http://www.skyhound.com/sh/skyhound.html

To reply remove spleen

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

On another group someone posted a color balanced version of this
picture to make it look more realistic...
http://www.donaldedavis.com/2004%20new/ESAGUSEV.jpg

I think what looks green in the ESA image are actually the dust devil
tracks that have been talked about so much. They should be more gray
then green.

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

On another group someone posted a color balanced version of this
picture to make it look more realistic...
http://www.donaldedavis.com/2004%20new/ESAGUSEV.jpg

I think what looks green in the ESA image are actually the dust devil
tracks that have been talked about so much. They should be more gray
then green.

I think the Don Davis image is probably the closest. The darker areas on Mars
tend to be various forms of a bluish-grey color. I think the ESA image color
rendition is way off, as much of the darker area shown as green is really made
up of dust-devil tracks. Clear skies to you.
--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

**********************************************
* Attend the 11th Annual NEBRASKA STAR PARTY *
* July 18-23, 2004, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************

I think the Don Davis image is probably the closest. The darker areas on Mars
tend to be various forms of a bluish-grey color. I think the ESA image color
rendition is way off, as much of the darker area shown as green is really made
up of dust-devil tracks. Clear skies to you.
--
David W. Knisely
Prairie Astronomy Club: http://www.prairieastronomyclub.org
Hyde Memorial Observatory: http://www.hydeobservatory.info/

**********************************************
* Attend the 11th Annual NEBRASKA STAR PARTY *
* July 18-23, 2004, Merritt Reservoir *
* http://www.NebraskaStarParty.org *
**********************************************

There's some VERY interesting replies to questions about the green
colors and more from an interview with ESA

"Certainly like the green in the Gusev crater picture or by looking
at the development of darker spots toward the South Pole which are tied
to seasonal variations, it certainly gives rise to the speculation that
there
could be algae." * Michael McKay, European Space Agency

Full article
http://www.earthfiles.com/news/news....tegory=Science

Too bad the beagle rover got lost, otherwise we'd be able to better
compare differences between what NASA shows us and what ESA shows us. I
can't wait for the ESA orbiter to become fully operational.

James Burk wrote:

ESA's Mars Express orbiter captured an image of Spirit's landing site
about a week ago. The image shows the exact location of Spirit is awash
in a shade of green. Don't believe me? Look at the image for yourself.
http://sci.esa.int/science-e/www/obj...objectid=34531

The same area was acquired by Odyssey in this false color image:
http://themis-data.asu.edu/img/V03415003_C321.html

Don Davis is an independent space artist / researcher who has processed
color images for Malin in the past. Here is his processing of the Gusev
landing site into "true color" from Odyssey data
http://www.donaldedavis.com/BIGPUB/DD_V03415003.jpg

What are your comments on this?

--
James Burk
MarsNews.com