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Dawn Mission now Nearing Asteroid Ceres
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tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
I suggested a natural nuclear fission reaction, like the one found at Oklo, Gabon. Tullio |
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
I suggested a natural nuclear fission reaction, like the one found at Oklo, Gabon. Here is how Oklo, Gabon nuclear fission reactor looks like. I think the salt theory is better. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1383 Credit: 2,098,506 RAC: 5 |
Something analogous to the natural nuclear reactor in Oklo, Gabon, found on the asteroid Ceres? That would be a remarkable discovery. The Oklo formation was active about 1.7 billion years ago, when the proportion of uranium 235 was at about 3.1 percent of natural uranium. This was sufficient for a nuclear reaction. Due to radioactive decay since then, U 235 is now about 0.7 percent of natural uranium, which is reportedly inadequate to support a nuclear reaction. Since all the elements that made up our solar system are thought to be of a like age, I'm inclined to think that this would hold true for Ceres, as well as Earth. |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
They find that the bright spots in the Occator crater do not reflect light in a manner consistent with ice. The favored explanation for the moment is salts (chlorides). I can hardly wait to see what spectroscopy is going to tell us about this. The idea of a 4 mile-high mountain of salt popping up with nothing similar around it is a little hard to buy. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1383 Credit: 2,098,506 RAC: 5 |
It's been suggested that a large impact at the exactly opposite point on Ceres surface, which has been seen, could have forced up this lone mountain. It would supposedly have done this by sending shock waves directly through the planet. A more far out suggestion would be that the mountain is a heap of tailings, left over from an extraterrestrial mining project. |
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
I can hardly wait to see what spectroscopy is going to tell us about this. The idea of a 4 mile-high mountain of salt popping up with nothing similar around it is a little hard to buy. Looks like something hit Ceres. If it was a comet then it's ice that we see. But that doesn't rule out salt mountains... |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
It's been suggested that a large impact at the exactly opposite point on Ceres surface, which has been seen, could have forced up this lone mountain. It would supposedly have done this by sending shock waves directly through the planet. For the first one to be true I think Ceres would have to be big ball of salt with a rocky surface. Otherwise, this focused shock wave just happened to pinpoint a huge isolated pocket and push it out. Not too likely. And I try to leave the sci-fi on the shelf. My vote is still for ice, but not as a natural geologic outcropping. I think it's conceivable that there could have been a fairly low speed impact with a comet that left an intact fragment on the surface. |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
There are nuclear reactors which use today's natural uranium as fuel, like the CANDU Canadian reactors and the now stopped CIRENE reactor in Italy. But they need heavy water as moderator. Tullio |
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
There are nuclear reactors which use today's natural uranium as fuel, like the CANDU Canadian reactors and the now stopped CIRENE reactor in Italy. But they need heavy water as moderator. Heavy water AKA deuterium oxide! https://en.wikipedia.org/wiki/Norwegian_heavy_water_sabotage |
Bob DeWoody Send message Joined: 9 May 10 Posts: 3387 Credit: 4,182,900 RAC: 10 |
They are saying that the most likely composition of the mysterious bright spots on Ceres is salt and not water ice. Bob DeWoody My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events. |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
They are saying that the most likely composition of the mysterious bright spots on Ceres is salt and not water ice. So we've got a large comet impact that digs this big hot crater, an enormous mountain of ice that flash melts into it and boils away leaving a residue in the lowest points of the crater. I could be totally off on that but I can't figure how else you're gonna get that much salt on an asteroid. |
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
They are saying that the most likely composition of the mysterious bright spots on Ceres is salt and not water ice. There are lot of salt in seawater. |
Bob DeWoody Send message Joined: 9 May 10 Posts: 3387 Credit: 4,182,900 RAC: 10 |
They are saying that the most likely composition of the mysterious bright spots on Ceres is salt and not water ice. I didn't say that I thought it is salt because it doesn't make any sense to me either. The problem is nothing that has been suggested makes much sense. Maybe by December when Dawn is down to a 200 mile high orbit the answer will be revealed. Bob DeWoody My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events. |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
I think the term "salt" is a little misleading - "mineral salts" would probably be more accurate. I'm picturing something more like ash. |
KLiK Send message Joined: 31 Mar 14 Posts: 1304 Credit: 22,994,597 RAC: 60 |
They are saying that the most likely composition of the mysterious bright spots on Ceres is salt and not water ice. & sea water BOILS in vacuum...leaves only salt residue... but it's probably just some sort of white mineral...not salt! ;) non-profit org. Play4Life in Zagreb, Croatia, EU |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30608 Credit: 53,134,872 RAC: 32 |
I think the term "salt" is a little misleading - "mineral salts" would probably be more accurate. I'm picturing something more like ash. I think most have forgotten what salt means when a chemist speaks it. |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Ceres, the largest object in the asteroid belt and closest dwarf planet to Earth, had been remarkable for its plain surface. New research suggests that most of the material that has struck Ceres in high-speed collisions has stuck — billions of years worth of meteorite material. What smacks into Ceres stays on Ceres A new set of high-velocity impact experiments suggests that the dwarf planet Ceres may be something of a cosmic dartboard: Projectiles that slam into it tend to stick. The experiments, performed using the Vertical Gun Range at NASA’s Ames Research Center, suggest that when asteroids and other impactors hit Ceres, much of the impact material remains on the surface instead of bouncing off into space. The findings suggest the surface of Ceres could consist largely of a mish-mash of meteoritic material collected over billions of years of bombardment. http://www.astrobio.net/topic/solar-system/meteoritescomets-and-asteroids/what-smacks-into-ceres-stays-on-ceres/ |
John D Anthony Send message Joined: 4 Sep 15 Posts: 177 Credit: 1,303,001 RAC: 1 |
What smacks into Ceres stays on Ceres Which adds a little weight to the idea that the pyramid mountain feature could be a large piece of a comet that impacted elsewhere on Ceres. I wonder if we're going to see others like it as we get closer. |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Mystery Solved? Ceres' Bright Spots Likely Made of Salt The mysterious bright spots on the dwarf planet Ceres may be composed of the same basic stuff that makes a foot bath feel so good, a new study reports. http://www.space.com/31323-dwarf-planet-ceres-bright-spots-likely-salt.html |
Lynn Send message Joined: 20 Nov 00 Posts: 14162 Credit: 79,603,650 RAC: 123 |
Those of us with some sort of brains worked that out a long time ago Lynn. I knew that Chris S. Just checking if you got the memo. :-) |
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