Spirit retrospective, - a few details from my current project Options

[Phil Stooke]

I'm working on Spirit at the moment. I will post a few examples of things as I go.

Right now the important job is updating the contemporary route map by locating the stops on HiRISE images. The existing maps at JPL, for the early part of the mission, were plotted on MOC images with inferior resolution and lighting, so I find many locations were about 15 or 20 m out. So at every site I am making circular panoramas (examples later) for comparison with HiRISE. Here's a first example, a map of the route during the Primary Mission. I have added a few extra placenames from the MER Analyst's Notebook at PDS.

Phil

[fredk]

So as far as seeing outside of Gusev, I've marked three locations on the view map:

We can clearly see the far rim of the smaller crater (New Plymouth?) at A. This map predicts that we should be able to see a bit farther to another smaller crater rim at B, but it's not clear to me whether we can see that in Phil's horizon pan or not.

I also wonder whether we can see some uncertain distance up Ma'adim Vallis to perhaps one of its walls, towards C. That would be somewhere around here on Phil's pan:

Unfortunately part of the Columbia Hills is in the way. But maybe there are pancam images that were taken from farther west (on approach to the summit) that would be unobstructed?

Phil: any chance you could post your original rectangular horizon pan at full res? Perhaps cropping out the foreground if the filesize is too big?

[ngunn]

We can clearly see the far rim of the smaller crater (New Plymouth?) at A. This map predicts that we should be able to see a bit farther to another smaller crater rim at B, but it's not clear to me whether we can see that in Phil's horizon pan or not.

B would, I think, break 100km but I wouldn't be surprised if it's not actually visible. If I remember rightly pgrindrod's visibility maps neglected the curvature of Mars. He was mainly concerned with closer features so that was fair enough. There's no way of knowing whether this one does or not. It's worth a thorough look though.

C: The view down the valley is definitely worth exploring in detail. If the most distant point on the horizon lies in that direction it should be possible to pinpoint the location and distance with the information available.

[fredk]

There's no way of knowing whether this one does or not.

From the first post by erwin in that old thread:

I use 128 pixel/degrees data, cropped gusev area, sphericise the heights according to Mars diameter.

So it seems he did take curvature into account.

Also, he says he cropped on Gusev, so any distant far wall of the Vallis may be outside of his cropped region. So his rendering of the C region may not show a distant wall that's actually visible...