Mars 'mystery cloud'?

[ronnietucker]

First, apologies if this has been posted before.

Second, yes I'm still a bit behind the times as this is from mid-March. More importantly:

Third, what do you guys think about this?

Amateur astrophotographer Wayne Jaeschke captured this image of a "terminator projection" rising up from the edge of the Martian disk at about the 1 o'clock position on March 22.

The inset photo is a 200 percent enlargement of the region around the projection.

The source page (below) has an animated GIF showing the protrusion moving with Mars.

Source: Cosmic Log - Mystery cloud spotted on Mars

[Peter Drew]

I've seen this reported elsewhere, it seems that it is unusual but not impossible.

[umadog]

Why can't it be a crater? That's what it looks like...

[neil phillips]

It is a very interesting feature, i wondered about a impact, but most seem to think thats not the case, i also seem to have captured this feature. On my images March the 11th it seems completely absent on the 14th at 22:54 ut it seems apparent some 15 mins later and it looks even more obviouse, but not sure if thats a effect of a better capture, or possibly coming into veiw more. Not to the standard of Waynes amazing capture i know. But i only had 245mm optics. And it does appear to show

something similar.

[umadog]

I wasn't quite thinking it was an impact event. I was envisaging a pre-existing crater with the far rim being caught by the sun and some of the interior in shadow. You see things l like that on the moon. The transient nature of the feature would be due to Mars' rotation. The feature is on the limb further from the sun, as you'd expect if this was the case. Does that make sense?

[neil phillips]

I wasn't quite thinking it was an impact event. I was envisaging a pre-existing crater with the far rim being caught by the sun and some of the interior in shadow. You see things l like that on the moon. The transient nature of the feature would be due to Mars' rotation. The feature is on the limb further from the sun, as you'd expect if this was the case. Does that make sense?

yes i see what you mean. But that angle of light would have to be rather rare or this effect would be seen more often i would have thought. would this angle only occur at rare times would be the question

Just did a rotated view with a similair colour balance to compare. Ive noticed the capture that shows it the most is also the one where the edge was very fuzzy. yet the avi was quite tight. Not sure what that could mean. But it could mean dust or cloud i guess, if its a real rendition, rather than a capture or processing problem, i cant say for sure. but i think the effect was real ?

[umadog]

That's true. I know there are some brief shadow-based phenomena that one sees on the moon, but I can't remember what they are now and I can't find links (I don't mean transient lunar phenomena, by the way). These events occur at predictable times based on the phase. If the phenomenon you captured is indeed a shadow-based event then it should occur repeatedly at the same phase. If it was a transient event (like a cloud) then you won't be able to predict it again in the same way.

[neil phillips]

That's true. I know there are some brief shadow-based phenomena that one sees on the moon, but I can't remember what they are now and I can't find links (I don't mean transient lunar phenomena, by the way). These events occur at predictable times based on the phase. If the phenomenon you captured is indeed a shadow-based event then it should occur repeatedly at the same phase. If it was a transient event (like a cloud) then you won't be able to predict it again in the same way.

Exactly, my feeling is this would have be noticed before. Unless theres a variable. Unless this variable was that the angle was particulaly brief ( yet theres quite a wide time span on recordings of this ) then it doesnt seem likely to me for that reason. Unless theres another variable that i cant think of ? For some reason my gut reaction has always been a major disturbance in this area, it appears on my image where its most obviouse theres quite a large disturbance. not just one region, but possibly two. But again im not sure if my capture, had a optical rather than real rendition ?

[umadog]

I can't see anything that looks that size and position on the Mars map, but maybe I just don't know Mars well enough or the map isn't good?

MARS MAP - MAP-SHARING - All maps of the world - Planet Mars