HAMO, (aka High Altitude Mapping Orbit) Options

[Bill Harris]

Yes, we'ev got a lot of puzzle-pieces to fit and assemble. The duck-feet look like chicken-feet which are starting to look like talons...

--Bill

[Phil Stooke]

Many great new pics at the Photojournal today including this new map:

http://photojournal.jpl.nasa.gov/catalog/PIA14703

including a gridded version. The coordinate system does not match the old one derived from Hubble images, a point that is causing some controversy, but I have little doubt that this will become the official coordinate system eventually. Another image in the new set defines the prime meridian marker:

http://photojournal.jpl.nasa.gov/catalog/PIA14715



Phil

[Phil Stooke]

This is a montage of frames from the shape model rotation movie also included in this release.

Phil

[stevesliva]

Also cataloged here:
http://dawn.jpl.nasa.gov/multimedia/vesta_dawn_gallery.asp

It's amazing how there are some very distorted ancient basins in the more tropical latitudes. And perhaps another giant basin that creates a gap in the south polar crater "rim." And the grooves aren't equidistant from the center of the southern crater, are they?

[DrShank]

Also cataloged here:
http://dawn.jpl.nasa.gov/multimedia/vesta_dawn_gallery.asp

It's amazing how there are some very distorted ancient basins in the more tropical latitudes. And perhaps another giant basin that creates a gap in the south polar crater "rim." And the grooves aren't equidistant from the center of the southern crater, are they?

Sharp eyes you have there! we have been discussing both aspects (ancient degraded craters, and the large "Giant basin" as you call it,
for several weeks. Vesta definitely has a history predating the large south polar basin.

[Phil Stooke]

http://www.dawn.mps.mpg.de/index.php?id=17...de9d31da5358ace


False color map of Vesta - very nice! It's not the full range of longitudes, only about 240 degrees long, and it doesn't register exactly with the recent base map (different projection), but it is interesting. This barely gets into the south polar depression at its southern edge.

Phil

[Juramike]

Love it! Sooo cool! How about that massive chasma across the middle? (Blue material in false color)

[Phil Stooke]

Approximate fit to the previous map.

Phil

[alan]

Could this be a basin?

[Gsnorgathon]

It's clearly a basin. The trick is, what caused it? That wonderful south polar impact threw up a huge amount of ejecta, a fair portion of which would have fallen back to the surface in all sorts of interesting ways. Shaking from the impact doubtless created some interesting structures. Based on what we know so far, Vesta's going to be a tough (and tasty!) nut to crack.

[dilo]

I had an interesting and very pleasant communication with Dr. Marc Rayman; he explained me that, until few hours ago, Vesta distance reported in the Simulator was based on extrapolated values of distance from asteroid centre, not height. I corrected my database and now is clear that Dawn is very close to HAMO final orbit, both in terms of height and speed (685 km and 135 m/s):

update: in the bottom/left plot I changed potential energy (now represented with the correct negative sign) and I added total energy curve (kinetic+potential).

[pablogm1024]

Love it! Sooo cool! How about that massive chasma across the middle? (Blue material in false color)

Hi Mike,
The blue material in the false color composite seems to be the ejecta blanket from the snowman crater(s). It is known to be remarkably dark and it was named in the past... Olbers Regio.
Cheers.

[Phil Stooke]

Yes! It's very interesting to overlay the Hubble compositional maps (in Li et al., Icarus 208 (2010) 238–251, for instance) over the new maps. Even quite small crater ejecta deposits line up very well. The two 'red' patches (false color) were clearly seen, but mapped as different things (Eucrite and weathered materials). No doubt we'll be getting team publications on this in due course.

Phil

[belleraphon1]

In Universe Today is an interview with Prof. Chris Russell and Carol Raymond.

South pole impact feature has been officially named Rhea Silvia after the mother of Romulus and Remus, mthyical mother of the Vestal virgins.

Prof. Chris Russell
“We have set ourselves a target to gather everything we know about the south pole impact feature and expect to have a press release from what ever we conclude at the GSA (Geological Society of America) meeting on October 12. “We will tell the public what the options are.

“We do not have a good analog to Vesta anywhere else in the Solar System and we’ll be studying it very intently.”

Sorry for the long url...

http://www.universetoday.com/89093/rhea-si...her/#more-89093

Craig

[belleraphon1]

GSA meeting 10/12/11... DAWN session

Dawn at Vesta: Initial Results from the Survey Orbit
http://gsa.confex.com/gsa/2011AM/finalprog...ssion_28729.htm

12 presentations!

Craig