Dawn Finds Possible Ancient Ocean Remnants at Ceres
Minerals containing water are widespread on Ceres, suggesting the dwarf planet may have had a global ocean in the past. What became of that ocean? Could Ceres still have liquid today? Two new studies from NASA's Dawn mission shed light on these questions.
The Dawn team found that Ceres' crust is a mixture of ice, salts and hydrated materials that were subjected to past and possibly recent geologic activity, and that this crust represents most of that ancient ocean. The second study builds off the first and suggests there is a softer, easily deformable layer beneath Ceres' rigid surface crust, which could be the signature of residual liquid left over from the ocean, too.
"More and more, we are learning that Ceres is a complex, dynamic world that may have hosted a lot of liquid water in the past, and may still have some underground," said Julie Castillo-Rogez, Dawn project scientist and co-author of the studies, based at NASA's Jet Propulsion Laboratory, Pasadena, California.
Constraints on Ceres' internal structure and evolution from its shape and gravity measured by the Dawn spacecraft (open, DOI: 10.1002/2017JE005302) (DX)
The interior structure of Ceres as revealed by surface topography (DOI: 10.1016/j.epsl.2017.07.053) (DX)
Previously: Dawn Spies Magnesium Sulphate and Possible Geological Activity on Ceres
Ceres's Cryovolcanoes Viscously Relax Into Nothingness
Organic Molecules Found on Ceres
Early Asteroids May Have Been Made of Mud Rather Than Rock
Dawn Mission Extended at Ceres
(Score: 4, Informative) by takyon on Monday October 30 2017, @06:37PM (1 child)
https://www.google.com/search?q=site:soylentnews.org+Ceres [google.com]
We have lots of articles on Ceres, including one 10 days ago. At some point jokes are the only thing that are going to be added unless the article proposes a mission there.
Actually, solar power can be used at Ceres. It can be used as far as Jupiter: https://www.jpl.nasa.gov/news/news.php?feature=4818 [nasa.gov]
The Dawn mission to Ceres uses solar power: https://en.wikipedia.org/wiki/Dawn_(spacecraft)#Specifications [wikipedia.org]
https://en.wikipedia.org/wiki/Sunlight#Intensity_in_the_Solar_System [wikipedia.org]
45.9 W/m2 minimum for Jupiter, 715 W/m2 maximum for Mars. Ceres is somewhere in between.
https://www.space.com/31584-dwarf-planet-ceres-colonization-the-expanse.html [space.com]
So about 2.5 more solar intensity than Juno is getting while orbiting Jupiter. Or is it?
This page [pveducation.org], with inputs 382.62, 414.01, 445.41 (x109 meters) gives me:
Perihelion = 382.62 x 109 m = 2.5577 AU
197.69 W/m2
Semi-major axis = 414.01 x 109 m = 2.7675 AU
168.85 W/m2
Aphelion = 445.41 x 109 m = 2.9773 AU
145.88 W/m2
So on average, Ceres gets a bit closer to 1/8 of the solar intensity near Earth-Moon rather than 1/10. Over three times what Jupiter gets, and Jupiter gets more like 1/27 than 1/25 what Earth gets.
The dip when approaching aphelion could be trouble, but it is entirely possible to use a useful amount of solar power at Ceres.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by bob_super on Monday October 30 2017, @06:42PM
Even if you can calculate that, do not tell the odds of a spacecraft surviving a visit to a planet in an asteroid belt.