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| Miscellaneous Discussion of non-Trek topics. |
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#31 |
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Rear Admiral
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Re: Russia reports amazing meteorite strike
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"They have to help the viewers let go. Firefly did a movie to wrap things up. Buffy the Vampire Slayer continued on as a comic book. Heroes gradually lowered the quality season by season until we were grateful it ended.” - Sheldon Cooper |
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#32 |
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Rear Admiral
Location: Near Manhattan ··· in an alternate reality
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Re: Russia reports amazing meteorite strike
Anyway, it meant for a terrific spread of videos capturing this meteorite impact event. Really fantastic and unprecedented. RussiaToday has a decent montage in one 2.5 minute video. What's really alarming is that the asteroid expected to pass by Earth this afternoon at some mere 17,000 miles away would have hit the Earth if our orbit around the sun was just 15 minutes behind! That's so damned marginal it's scary as all hell. Who's to say that those 15 minutes will be made up on the next fly-by, making it an impact instead some 30 years from now?
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Remembering Ensign Mallory. |
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#33 |
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Vice Admiral
Location: I'm at WKRP
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Re: Russia reports amazing meteorite strike
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Baby, you and me were never meant to be, just maybe think of me once in a while... |
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#34 |
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Rear Admiral
Location: fresno, ca, us
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Re: Russia reports amazing meteorite strike
That sonic boom was HUGE! I've heard some, mostly when I was younger but also some with the shuttle landing in the desert, and they were never that loud. What causes the volume? Size? Speed? |
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#35 | ||
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Rear Admiral
Location: Who is John Galt?
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Re: Russia reports amazing meteorite strike
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#36 | |||
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Writer
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Re: Russia reports amazing meteorite strike
A friend of mine whose husband is an asteroid expert pointed out on Facebook that close flybys and atmospheric explosions like this happen every single day -- it's just that most of the explosions are smaller or happen over unpopulated areas, and most of the flybys are by smaller objects that don't get as much advance notice. The coincidence is not that these things happened within a day of each other, since that's actually pretty commonplace; the coincidence is that they both got so much notice.
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Christopher L. Bennett Homepage -- Updated 5/28/13 with discussion of Rise of the Federation Book 1. Written Worlds -- My blog |
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#37 |
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Admiral
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Re: Russia reports amazing meteorite strike
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#38 |
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Vice Admiral
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Re: Russia reports amazing meteorite strike
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"You know. 1966? Seventy-nine episodes, about thirty good ones." - Phillip Fry describing Star Trek, Futurama |
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#39 | |
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Rear Admiral
Location: Near Manhattan ··· in an alternate reality
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Re: Russia reports amazing meteorite strike
I also understand that orbits can be calculated precisely, however there is always a margin for error when it comes to passing objects. We can't accurately predict how other gravitational forces will affect the object, including this present passing. As Sojourner pointed out, the asteroid will experience a change to its path due to the gravitation forces from Earth on this fly-by. They may be able to predict if it will bend it in such a way as to bring it closer or further away on the next pass, but I don't believe they can make an accurate estimate on the exact distance it will pass next time. Even this time, there was open speculation on whether or not a satellite might be damaged since it passed inside the ring of geosynchronous weather and communications satellites. If measurements were truly precise, they would have been confident to say there was no possibility of a satellite being damaged. Relatively speaking, for a passing object to fly within the ring of geosynchronous satellites is EXTREMELY CLOSE compared to the orbit of the moon. I wonder how much advance warning we'll have with a larger object, say of 3x the size. Something like that could cause a massive disruption to our environment and extensive damage to life and property if it landed in a densely populated area.
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Remembering Ensign Mallory. |
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#40 |
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To boldly go...
Location: Kansas City
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Re: Russia reports amazing meteorite strike
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Just because it's futuristic doesn't mean it's practical. |
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#41 |
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Rear Admiral
Location: Near Manhattan ··· in an alternate reality
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Re: Russia reports amazing meteorite strike
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Remembering Ensign Mallory. |
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#42 | ||||
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Writer
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Re: Russia reports amazing meteorite strike
The only uncertainties come from unknown objects whose gravity could influence its course, but we've identified most of the large near-Earth asteroids by now, so there's not that much we don't know about objects that might affect 2012 DA14's orbit -- which is why the margin of error is on the order of one in five million. And of course it's not like we're going to forget it's there. Assuming civilization doesn't fall from some other cause in the interim, we're naturally going to keep tracking it, so if something does change its course, we'll know about it.
Besides, if you look at the table above, there is no point in the next century where Earth's position will even be within the margin of error in the calculations, even the ones with the largest uncertainty. Yes, there is always a margin of error in orbital calculations, a cone of possible paths an object might take from its current observed position. But it doesn't matter how wide that cone is if it never intersects Earth's path. This is why you so often hear reports that some asteroid might potentially hit Earth get quickly followed up with, "no, it won't hit after all." It's because initially the margin of error in the object's course is wide enough that the Earth's position at the point of intersection is within the cone of probabilities; but as further observation refines our estimate of the object's course, the cone narrows and no longer overlaps Earth's position. As long as the cone doesn't intersect Earth, it doesn't matter how precise it is beyond that; whether it's got a 1-kilometer or a 100,000-kilometer margin of error is irrelevant if the minimum possible distance it would pass by Earth is 500,000 kilometers. Either way, the probability of an impact is zero.
EDIT: Here's an article with more information about the Russian event and the effort to identify and track near-Earth objects, as well as an explanation of what caused the explosion. Last edited by Christopher; February 15 2013 at 11:44 PM. |
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#43 |
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The Old Mods and the New
Location: Huntington Beach, CA
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Re: Russia reports amazing meteorite strike
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"The fundamental cause of trouble in the world is that the stupid are cocksure while the intelligent are full of doubt." - Bertrand Russell |
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#44 | |
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Commodore
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Re: Russia reports amazing meteorite strike
WHICH WE CAN'T EVEN BREATHE!!!1!!1!one!!1!1
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#45 |
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Commodore
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Re: Russia reports amazing meteorite strike
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