Viking 2 Landing Site

HERE is a view of the horizon of Mars from Viking Lander 2, shown with EXTREME vertical exaggeration. That prominent hill in the distance is a type of crater called a 'pedestal crater', named Goldstone after the Deep Space Network tracking complex. Another hill like this is very faintly visible north of the lander, just peeking over the boulders on the horizon (not illustrated here).

Using these and other features, I have used horizon topography to refine the position of the Viking 2 lander on the surface of Mars. This was attempted for Viking 1 (but the result people have used for the last 20 years is now thought to be incorrect) and done successfully for the recent Pathfinder, but never for Viking 2 because of the paucity of horizon features. My approach now makes this possible.

HERE is a Viking Orbiter view of the landing area. Light is from the left, north is a bit left of 'up'. The image covers a region about 20 by 25 km. Goldstone is the feature labelled G. The other visible hill is labelled H. The blue line is the position of the lander estimated from radio tracking. The red dot labelled V is the lander location determined from the intersection of azimuths from G and H. It lies within a shallow hollow, possibly a deflation pit, in the ejecta blanket of a large crater called Mie, some 150 km away to the east. The horizon around the lander is mostly the rim of the pit. The sharper part of this image is a super-resolution composite of two Viking Orbiter frames. The fuzzier area to the upper left is from a single frame.

This work is described in more detail in a paper now in press in Earth, Moon and Planets. I have also looked at the Viking 1 site, but it almost certainly falls outside the available high resolution imagery from Viking, and we must await better data from Mars Global Surveyor to find it. Meanwhile, here are some reprojected lander panoramas to show the surroundings of each site. The Viking images are composites of the panoramas made from each of the two cameras on each lander. By combining the two camera mosaics, a minimal amount of the actual surface is concealed by parts of the spacecraft. North is (approximately) at the top in all three views. Note, though, that the radial scale is variable and is distorted to exaggerate the area around the landers themselves.... and the height of horizon features is very exaggerated as well. In other words, these are not accurate maps, but they give a different (and I think helpful) view of the landing sites. I will process future panoramas in a similar way.

Viking 1 site
Viking 2 site
Pathfinder site