[meteorite-list] Strange Martian Surface Feature

From: Dave <Dave_at_meteoritecentral.com>
Date: Thu Apr 22 10:02:25 2004
Message-ID: <003d01c1c51c$d3d82ac0$99e67cd1_at_dave>

I put the Narrow Angle Camera image into Photoshop 5.5, rotated it to get a
fresh perspective (basically upside down compared to the extreme closeup on
the original web page), and enlarged the image considerably. Looks to me
like the bright reflection in the closeup is the central uplift in an impact
crater. The crater shows up better in mine than in theirs, but is less
obvious in mine when I rotate it back the way the image on the web site is.
The rotation "changes" the way you perceive it.

Also, in my image the "arches" are far less prominent (perhaps the web site
used different software than I did). In my rotated image, they look
distinctly concave rather than convex, more like features you would expect
to see at the bottom of a cliff which is where they appear to be.

Of course, I have no expertise in interpreting orbital images of Mars so I
am just saying the way it looks to me. I do know from many other pictures,
however, that interpreting features on the Martian surface is a tricky
business and that the same feature can be perceived in different ways
depending on how the picture is oriented. For instance, there are a lot of
images I've seen where rotating the image changes a nice field of craters
into a field of low hills. It pays to be cautious with this stuff!

Dave Hostetter


> > Ok, it's a little off topic, but... A friend of mine belongs
> >to a group one of whom found the following site displaying an
> >image of a Martian surface feature:
> ><http://www.enterprisemission.com/samp5.htm>
> > This site is one maintained by a notorious whacko and
> >fringe-theorist, Hoagland, the author of Monuments of Mars, so I
> >told them he was a nutcase; forget it. And they properly came
> >back me with "Forget about the nutcase; what the Hell is this?"
> >And I didn't have a good answer. In fact, I don't think I've got
> >any answer. Enigmatic is the best description I could come up
> >with and that's just a word for an excuse.
> > Since the link to the original Mars Observer Narrow Angle
> >Camera image on the Hoagland site is broken, here's the correct
> >link for those that want to puzzle over it in greater detail:
> ><http://www.msss.com/moc_gallery/ab1_m04/images/M0400291.html>
> > Any ideas? What the Hell is this?
> >
> >Sterling K. Webb
> >
Received on Wed 06 Mar 2002 09:40:11 AM PST