[X] My Assistant

[peter59]

T13 - Targeted Distant Look (Huygens Landing site)

Attached thumbnail(s)

 

[Juramike]

I matched up the Huygens landing site DISR mosaic PIA06438 with the T8 RADAR Swath zoomed to the same scale. In the second graphic I've indicated the "spooky dude" formation in light blue. These pixels are almost resolvable in the RADAR as slightly lighter pixels compared to immediate neighbors. The darker portion of the channel seen in the DISR mosaic is also apparent in the T8 RADAR swath zoom area. (The "spooky dude" formation is just south of a RADAR stitch zone).


I've created a colorized terrain map of the Huygens landing site based primarily on the DISR mosaic, but also including the T8 RADAR data, as well building on the information presented in Soderblom's recent article (Soderblom et al. Planetary and Space Science (2007), doi:10.1016/j.pss.2007.04.015 "Topography and geomorphology of the Huygens landing site on Titan.")


In the tectonic ridge (bright island) terrain, yellow is for the upper ridge portion identified by both DISR topology model and RADAR bright ridgetops in the T8 Swath and T13 distant view. The eroded ridge terrain mantle deposits (RADAR bright gray) are left uncolored (thus gray) in the graphic..

For the channel terrain, lighter shades of blue are for the brightest (DISR) upper channel deposits (such as the spooky dude formation) while darker shades of blue and purple are for the DISR dark and RADAR dark smooth ice muds. There is a much larger range of DISR shading than represented by these five colors. This would be a really fun place to try contrast enhancement to bring out all the subtleties.

The lightest blue terrain could correspond to low density nanoporous clathrate cobbles (cryopumice) that has been floated into drifts during flood events. These could be the identity of the cobbles that we saw in the final Huygens images on the surface.

Another possibility is that the light blue terrains could be the extension of the tectonic ridge across the channel, and that this portion of the ridge has been breached, carved, and heavily eroded during flooding and tidal events through the channel. (An argument against these being original ridge sections is that these have been breached crossways at a later point during weaker flows – that indicates these are easily carved materials. These are seen in closeup images of the spooky dude formation close to the touchdown area)

On the southeastern shore of the channel, there is another little island-section of bright tectonic ridge (the island to the SE of the Huygens landing site), as evidenced by RADAR bright terrain in the T8 Swath.

The mantle of the SE Island that extends into the channel (indicated in the diagram by orange semi-transparent shading) looks similar by RADAR to that of the NW island, but by DISR the terrain looks very different. By DISR, the mantle doesn't have any obvious channels - it looks like a confusing mess of visible bright and visible dark terrain. Although these images are not well-resolved, there appear to be a series of pits among the bright dark patterns. Is it possible that this is some of the "rotted terrain" like was described in post 203, Equatorial Sand Seas thread?


Overall, I think this is a pretty cool example of the information and possible interpretations you can extract by combining low-altitude visual (DISR) and orbital RADAR information. And it allows a good characterization of "channel" terrain on Titan.

-Mike