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Science (non-SETI) :
Asteroid close pass.
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Author | Message |
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Lint trap Send message Joined: 30 May 03 Posts: 871 Credit: 28,092,319 RAC: 0 |
The nuclear weapons, which the major powers still have on hand, might be turned to good account. One, or a few of these, exploded in the vicinity of (not in or on) an asteroid, might nudge it off a course headed for Earth. Isn't that risking sending radiation charged shards into the Earth? I like the gravity-steering solution best, but it relies on advanced detection, long enough for the gravity 'partner' to be positioned and for the effect to change the objects orbit. Perhaps, when we learn to create micro-dot black holes, we could shoot one of them at a threatening object. The object would be absorbed, and the orbit of the black hole would not be affected, taking it harmlessly out of the solar system eventually. Lt |
SciManStev Send message Joined: 20 Jun 99 Posts: 6658 Credit: 121,090,076 RAC: 0 |
I agree with the gravity solution. The possible scenarios of what to do should an asteroid be on a collision course can vary depending on what the make up of the asteroid is. It could be iron, rock, or even loose gravel. From what I have heard, exploding one is a bad option, and deflecting one wouldn't be as effective as one would think. What seems to me to be the most reasonable threat deterant, is the tractor beam scenario. Park a satelite near the asteroid, and use the combined gravity of the two to slowly move it in a slightly different angle. The satelite doesn't have to be huge, and it will work regardless of the make up of the asteroid. The real tricky part is getting the earth to act in unison, and set up at least some sort of deterance prior to an event being discovered. Once discovery is made, perhaps any existing deterance could be trimmed to the exact threat. There are still other events that could wreck us. Life is risky. Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31003 Credit: 53,134,872 RAC: 32 |
Mass makes the difference. A small rock is easy to change course. A big rock requires more time and effort. Early discovery is the key. A small impulse delivered half an orbit away makes a huge difference. It requires a huge impulse to change course a few days out. All we have to do is make it get here and hour earlier or later and earth won't be there to be hit. Half an orbit away a change of less than a foot a second would be plenty. For most of the stuff that gets near us an ion engine could give it enough of a shove in a couple months time. The big rocks wold require a bit more but a delta rocket would be plenty. However if we only have a few days before splat, we better dig bunkers. We don't have the power necessary to change the orbit. Bombs are not an option. You trade one monster splat for a dozen huge splats and a few thousand whacks. |
Lint trap Send message Joined: 30 May 03 Posts: 871 Credit: 28,092,319 RAC: 0 |
Mass makes the difference. Yes, and velocity. (f=ma) Lt |
Marie Send message Joined: 19 Oct 11 Posts: 3 Credit: 3,574 RAC: 0 |
Michael, thank you for the informations. So, did you manage to watch it? I wanted to try, even if I'm still a beginner but the night is clowdy here in Switzerland. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Unfortunately, I didn't see the object. I forgot to reckon with the brightness of the nearly full Moon in the same part of the sky. It reduced the visibility of dim objects markedly. The good news is that some better and better radar images and even a rudimentary motion study of the object are already becoming available. Google image has these under the search term: YU55. Youtube has the motion study. |
Bob DeWoody Send message Joined: 9 May 10 Posts: 3387 Credit: 4,182,900 RAC: 10 |
We need for one of these objects to hit the moon where it could be seen from earth, then maybe everyone would get the point. Shoemaker/Levi 9 should have gotten the point across but only the scientific community got to see it as it happened. Well time delayed because of the distance. 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. |
SciManStev Send message Joined: 20 Jun 99 Posts: 6658 Credit: 121,090,076 RAC: 0 |
I'm very happy! The asteroid did indeed, miss us! :D Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
Bob DeWoody Send message Joined: 9 May 10 Posts: 3387 Credit: 4,182,900 RAC: 10 |
So, has the new trajectory been analyzed to determine whether we are a target on it's next pass? 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. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
Inspection of the best images of YU55 to date, from a distance of about 860,000 miles, seems to reveal 'puzzling structures'. That's what NASA scientists called them in a recent press release. To my eye, there appears to be a large, rounded central area surrounded by a wide flattish rim. The rim appears about 1/6 as broad as apparent diameter of the entire object, the rounded area covering the rest of the visible surface. Assuming this isn't an illusion caused by the method of producing the image from radar beams, it would, I think, qualify as a very puzzling configuration. |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
Appearance is probably due to the position of the illuminating energy. The fact that is apparently spherical might mean that it is composed of heavy material. Perhaps the core remnant of a much larger object ?? |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
I'm told that the radar beam, used to make the image. comes in from above. The top of the picture actually shows the side of the object which faces Earth. Two sequences of images stitched together into crude 'movies' to display the object's spin, show it maintaining a rounded aspect, no matter which way its turns *********. If this is a dense object, it seems it would have been classed with the iron asteroids (Class M), which reflect a good deal of light. On the basis of its color, it was given a C classification, that of carbon rich mineral grains, which are much darker. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
As it turns out, small, roughly spherical asteroids, even ones with equatorial ridges, are not unheard of. Both features are due to centrifugal force, caused by their rotation. This force acts on loosely consolidated bodies, sometimes called 'rubble pile' asteroids, forcing material out from the center in all directions, and especially at the equator, where the force is strongest. ********* Considering that all this is widely known in the scientific community, the nature of the 'puzzling structures' the astronomers reported seeing, and admitted they couldn't explain, remain a mystery. Perhaps they're waiting for closer-in images before even attempting to describe these structures. The best images seen so far are from a distance of 860,000 miles. Those from the minimum distance of ~200,000 miles are awaited. The latter imply an increase of resolution by four times. |
Michael Watson Send message Joined: 7 Feb 08 Posts: 1387 Credit: 2,098,506 RAC: 5 |
The Goldstone space radar facility, in the Mojave Desert, California, will be used to observe YU55 through the middle of the day on the 18th, Universal Time. Presumably, after that, there will be more time for them to release new, better, images, motion studies, an improved shape model, and other information. We should hope to hear, then, a description, at least, of what the astronomers called 'puzzling structures'. |
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