Would like identification of some lake-like features in MGS photo

[[Mod. note -- excess whitespace trimmed -- jt]]

Hi, you experts! ;-)

I stumbled over this Mars Global Surveyor photo,
url: http://www.msss.com/moc_gallery/m07_m12/images/M09/M0902042.html
"MOC narrow-angle image M09-02042", which covers an approx 2.8 km wide and
171.3 km high strip if I understand it correctly.

I have copied the photo he
url: http://home.no.net/dubjai/misc/moc/M0902042.jpg [ca. 836 kiB]
This is, as I understand it, near the south pole of Mars.

At the very bottom there are some features which to my untrained eye look
very much like lakes, which I have cropped out of the main photo and
placed here (just 19 kiB):
A: url: http://home.no.net/dubjai/misc/moc/nederste_av_M0902042.jpg
I wonder what this is -- I received no reply at all when mailing the
public "astronomy question" address at the University of Oslo.

Also, but less interesting, I wonder if the features that look like ice
roses (hundreds of meters wide), e.g. at the very top of that photo,
B: url: http://home.no.net/dubjai/misc/moc/oeverste_av_M0902042.jpg.
are formations due to freezing and thawing, or something else?

Also -- this is one heck of feature-rich photo! ;-) -- I wonder about
the seemingly rectangular kilometer-wide depression or crater (whatever)
in the middle of the picture,
C: url: http://home.no.net/dubjai/misc/moc/midterste_av_M0902042.jpg

But, first and foremost, does anyone know about the looks-like-lakes at the
bottom, in (A)? In addition to those at the very bottom there's a smaller one
a little bit upward from the bottom. The smooth gray-color gradients in the
interiors of the features might be shadow, but it doesn't look that way.

TIA.,

- Alf

* (Alf P. Steinbach) schriebt:
[[Mod. note -- excess whitespace trimmed -- jt]]

I stumbled over this Mars Global Surveyor photo,
url: http://www.msss.com/moc_gallery/m07_m12/images/M09/M0902042.html
"MOC narrow-angle image M09-02042", which covers an approx 2.8 km wide and
171.3 km high strip if I understand it correctly.

I have copied the photo he
url: http://home.no.net/dubjai/misc/moc/M0902042.jpg [ca. 836 kiB]
This is, as I understand it, near the south pole of Mars.

At the very bottom there are some features which to my untrained eye look
very much like lakes, which I have cropped out of the main photo and
placed here (just 19 kiB):
A: url: http://home.no.net/dubjai/misc/moc/nederste_av_M0902042.jpg
I wonder what this is -- I received no reply at all when mailing the
public "astronomy question" address at the University of Oslo.

Well, I finally got an answer to this particular question in the
unmoderated [sci.astro] group -- no responses in this group!

All that was needed to make sense of it was to turn the picture
upside down. In the original photo the eye was fooled by the
lighting. What looked like lakes in the original photo looked
like strange droplet-formed mesas in the rotated photo -- strange
but not totally inexplicable.

It turned out that one small detail, a heart-shaped mesa, had been
published separately at much higher resolution.

I've placed comparisions of the original photo and 180 degrees
rotated he
url: http://home.no.net/dubjai/misc/in_or_out/index.html.

That page also includes the blow-up of the heart-shaped mesa, showing
more clearly that the features are indeed mesas.


Also, but less interesting, I wonder if the features that look like ice
roses (hundreds of meters wide), e.g. at the very top of that photo,
B: url: http://home.no.net/dubjai/misc/moc/oeverste_av_M0902042.jpg.
are formations due to freezing and thawing, or something else?

Still no answer to this, or even any suggestion as to what they could be.


[[Mod. note -- You might also try over in sci.space.science ; a lot
of planetary-science types seem to post there. -- jt]]



Also -- this is one heck of feature-rich photo! ;-) -- I wonder about
the seemingly rectangular kilometer-wide depression or crater (whatever)
in the middle of the picture,
C: url: http://home.no.net/dubjai/misc/moc/midterste_av_M0902042.jpg

Ditto.

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