The Dawn spacecraft has found evidence of magnesium sulphate (epsom salts) on Ceres, causing the mysterious bright spots:
The US space agency's Dawn satellite continues to return remarkable images from the dwarf planet Ceres. Now just 385km above the surface (lower than the space station is above Earth), the probe has revealed new features inside the mini-world's Occator Crater. This is the 92km-wide depression that has multiple bright spots of what are thought to be exposed salts.
[...] "The intricate geometry of the crater interior suggests geologic activity in the recent past, but we will need to complete detailed geologic mapping of the crater in order to test hypotheses for its formation." Scientists think the bright spots are deposits of epsom salts (magnesium sulphate), the trace remains of briny water-ice that at one time became exposed on the surface.
With no atmosphere on the dwarf planet, the water content would have rapidly vaporised, leaving only the magnesium sulphate spots. Ceres likely has quite a lot of buried water-ice. This idea is being investigated by the satellite's GRaND instrument, which senses neutrons and gamma rays produced by cosmic ray interactions with surface materials. It is a means to understand the chemistry of the top metre or so of Ceres' rocky "soil".
Lunar and Planetary Science Conference.
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Organic Matter on Dwarf Planet Ceres More Abundant than Thought
A new analysis of data collected by NASA's Dawn orbiter suggests that organic molecules may exist in surprisingly high concentrations on the surface of Ceres. The study [DOI: 10.1029/2018GL077913] [DX] appears in the journal Geophysical Research Letters.
[...] To get an initial idea of how abundant those compounds might be, researchers compared the [Visible and Infrared Spectrometer] data from Ceres with lab reflectance spectra of organic material formed on Earth. Based on that standard, they concluded that 6-10% of the spectral signature they detected on Ceres could be explained by organic matter.
But for this the new study, Southwest Research Institute researcher Hannah Kaplan and co-authors wanted to re-examine those data using a different standard. Instead of relying on Earth rocks to interpret the data, they turned to an extraterrestrial source: meteorites. Some meteorites have been shown to contain organic material that's slightly different from what's commonly found on our own planet. And the new analysis shows that the spectral reflectance of the extraterrestrial organics is distinct from that of terrestrial counterparts. [...] "We estimate that as much as 40-50% of the spectral signal we see on Ceres is explained by organics. That's a huge difference compared to the 6-10% previously reported based on terrestrial organic compounds."
[...] There are two competing possibilities for where Ceres' organics may have come from. They could have been produced internally on Ceres and then exposed on the surface, or they could have been delivered to the surface by an impact from an organic-rich comet or asteroid.
Previously: Organic Molecules Found on Ceres
Related: Dawn Spies Magnesium Sulphate and Possible Geological Activity on Ceres
Ceres May Have Had a Global Surface Ocean in the Past
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
NASA's Dawn Mission to Asteroid Belt Comes to End
NASA's Dawn spacecraft has gone silent, ending a historic mission that studied time capsules from the solar system's earliest chapter.
Dawn missed scheduled communications sessions with NASA's Deep Space Network on Wednesday, Oct. 31, and Thursday, Nov. 1. After the flight team eliminated other possible causes for the missed communications, mission managers concluded that the spacecraft finally ran out of hydrazine, the fuel that enables the spacecraft to control its pointing. Dawn can no longer keep its antennae trained on Earth to communicate with mission control or turn its solar panels to the Sun to recharge.
The Dawn spacecraft launched 11 years ago to visit the two largest objects in the main asteroid belt. Currently, it's in orbit around the dwarf planet Ceres, where it will remain for decades.
Also at Ars Technica, The Verge, and Science News.
Previously: NASA's Dawn Spacecraft Nears the End of its Mission
NASA Retires the Kepler Space Telescope after It Runs Out of Hydrazine
Related:
Pluto and Ceres
After Eight Years, NASA's Dawn Probe Brings Dwarf Planet Ceres Into Closest Focus
NASA's Dawn Orbiter Finds a Mountain on Ceres
Dawn Spies Magnesium Sulphate and Possible Geological Activity on Ceres
Ceres' Cryovolcano Ahuna Mons Formed in the Geologically Recent Past
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
Ceres May Have Had a Global Surface Ocean in the Past
Bright Areas on Ceres Suggest Geologic Activity
Dawn's Orbit Around Ceres: A New Low
Dawn's Orbit Around Ceres: First Images
Dawn Spacecraft Captures Closest-Ever Images of Ceres' Shiny Occator Crater
(Score: 2) by bob_super on Wednesday March 23 2016, @07:06PM
With all the stuff that "vaporizes" into space, I ain't getting into a near-lightspeed ship until we actually invent those sci-fi shields. You can take my seat to Proxima Centauri.
(Score: 0) by Anonymous Coward on Wednesday March 23 2016, @08:29PM
I'll take the warped space method that actually seems feasible, though not 100% sure whether it's susceptible to small interstellar collisions or just significantly gravitational ones.
(Score: 3, Interesting) by Fluffeh on Wednesday March 23 2016, @09:32PM
From what I understand of the theory, the a ship in a warped space bubble-thing wouldn't impact any particles at any higher velocity than if it wasn't in the warp. That's the freaky thing with the whole concept of the warp space drive. The ship isn't actually travelling "faster" than it can accelerate to via normal propulsion, but the warp makes it travel in less time, not faster (which I totally get sounds to be a oxymoron, but really, it isn't). So, even though the apparent velocity of the ship is 0.1c (or faster) particles hitting the ship would be slamming into it at velocities orders of magnitude lower.
What I would be concerned about is the theorized buildup of exotic particles at the front of the ship and whether some of that buildup seeps into the space where the ship itself is.
(Score: 2) by bitstream on Wednesday March 23 2016, @07:54PM
I knew it! The Aliens have resorted to bribe NASA when their waves didn't penetrate their hidden clothes foil and ordered them to use their secret fast than light craft to go there, open door, salt the planet, go home and then claim. "See no secret base, just salt!".
//Pointy haired hired consultant on security matters
Oh, btw there's no hackers. It's an illusion.. oh w8.. ¤#¤#¤#%)¤%NO CARRIER.
(Score: 0) by Anonymous Coward on Wednesday March 23 2016, @08:07PM
This will one day be the trailer park of the solar system.
(Score: 3, Informative) by PartTimeZombie on Wednesday March 23 2016, @10:26PM
Epsom salts are good for citrus trees. I sprinkle some around my lemon tree every spring and autumn.
You're welcome.
(Score: 0) by Anonymous Coward on Thursday March 24 2016, @03:41AM
The compound is also used as a laxative. Could comet mining finally make regularity affordable for the masses?
(Score: 2) by frojack on Wednesday March 23 2016, @11:41PM
We can start mining the asteroids any day now.
No, you are mistaken. I've always had this sig.
(Score: 2) by bitstream on Thursday March 24 2016, @12:30AM
So the article [bbc.com] states that "there is likely a global layer of ice and salt under the rocky rubble that coats Ceres". So there's perhaps a gigantic source of MgSO4. Perhaps one can make (space) vehicle parts from the magnesium and rocket fuel? And the "ice" is H2O? anyway there seems to be ammoniated phyllosilicates [nih.gov] (NH3) so there definitely rocket fuel potential.
With a gravity at 0.029 g and a escape velocity of 0.51 km/s it should be relatively easy to land and take of. The problem is likely to stay at the ground.
So maybe this planet can have its uses in the future of space faring?
(Score: 0) by Anonymous Coward on Thursday March 24 2016, @04:02AM
Hey, excuse me!! Ceres is not a planet!!! Despite its shape and the fact that it orbits the Sun, it's merely a dwarf planet [wikipedia.org]. It hasn't cleared its orbit of debris, like a real planet would. Let's not dilute the term "planet" by using it for anything spherical that goes around a star.
(Score: 2) by bitstream on Thursday March 24 2016, @05:26AM
Sorry, let's demote it to a dwarf planet then ;-)
The resources are still there regardless of this issue :p Though the asteroid belt seems like an ominous place to do things. Asteroid strikes are perhaps more likely to occur there?
(Score: 0) by Anonymous Coward on Thursday March 24 2016, @12:42PM
Question;
is the asteroid belt going to stay an asteroid belt forever or will it form a planet Ceres? Has anyone modelled how long that would still take for Ceres to clear its orbit?
(Score: 0) by Anonymous Coward on Friday March 25 2016, @03:34AM
I'm not from the IAU police; I just dropped in to give bitstream a bit of a ribbing.
Someone wrote in Wikipedia [wikipedia.org] that the asteroid belt is thought to have lost ~99.9% of its original mass as objects were displaced from it by Mars and Jupiter, while "there has been no significant increase or decrease in the typical dimensions of the main-belt asteroids." Someone there wrote that the hypothesis that the asteroids are the remnants of a smashed-up planet [wikipedia.org] has fallen out of favour. Pity, that.
(Score: 1) by o_o on Thursday March 24 2016, @12:06PM
So maybe this planet can have [..]
Dwarf planet.
(Score: 4, Funny) by Some call me Tim on Thursday March 24 2016, @01:09AM
Just this morning I opened the cabinet under my sink and found Dawn and Epsom salts. Small world 'eh!
Questioning science is how you do science!