Posted on 04/18/2005 7:21:31 AM PDT by aculeus
A HUGE asteroid which is on a course to miss the Earth by a whisker in 2029 could go round its orbit again and score a direct hit a few years later.
Astronomers have calculated that the 1,000ft-wide asteroid called 2004 MN4 will pass by the Earth at a distance of between 15,000 and 25,000 miles about a tenth of the distance between the Earth and the Moon and close enough to be seen with the naked eye.
Although they are sure that it will miss us, they are worried about the disturbance that such a close pass will give to the asteroids orbit. It might put 2004 MN4 on course for a collision in 2034 or a year or two later: the unpredictability of its behaviour means that the danger might not become apparent until it is too late.
As a safety precaution, some experts are calling for 2004 MN4 to be tagged with a transponder that would constantly radio its position. Scientists hope that this would provide enough warning to allow emergency action if necessary, possibly by diverting the object away from the Earth.Other instruments on the probe could provide information about its composition.
Benny Peiser, from Liverpool John Moores University, who is an expert on asteroid hazards, said: We dont know what that asteroid is made of and that might influence the way its affected by the Earths gravitational pull. There are other close approaches, in 2034 and 2035. In all likelihood it will produce an orbit that will not intercept the Earth, but we dont know.
The asteroid is big enough to cause damage on a regional scale, with an expected impact equivalent to a 1,000-megatonne explosion. It was discovered last June and its orbit plotted in detail by December. Startled astronomers calculated at one point that its chances of a direct hit on Friday, April 13, 2029, were 1 in 38. But additional calculations have set those fears to rest. The asteroid is now expected to miss but come close enough to be below the altitude of TV satellites. It should be visible as a rapidly moving point of light.
Brian Marsden, of the Harvard-Smithsonian Centre for Astrophysics in Cambridge, Massachusetts, expects the close encounter to increase the frequency of the asteroids orbit, creating the possibility of further close encounters every five to nine years.
An interceptor mission is feasible and Dr Peiser said that an opportunity would arise in 2012, when 2004 MN4 will be ten million miles from Earth. Thats not a big distance as far as space missions go, he said.
This is most likely not the object with our number on it, but one day we will have to address this question and well need the technology. A transponder mission should not be too complicated or costly, and would provide a lot of vital data.
Copyright 2005 Times Newspapers Ltd.
Oops. That should've been;
Don't worry, we'll die before then.
http://www.freerepublic.com/focus/f-news/1385922/posts
The planets and rocks transfer kinetic energy between themselves. Earth would change direction a little and the asteroid would change direction a lot more. They could even speed up or slow down.
> So Jupiter hasn't been the solar system vacuum for billions of years?
Yes, it has. But 2004MN4 is in a reasonably circular orbit, very similar to Earths. Jupiter has served to hoover up the asteroids and comets in highly elliptical or hyperbolic orbits that come somewhat near it. What large planets like Jupiter do is take care of very eccentric orbits; Jupiters effect on circular orbits distant from it is just minor chaotic orbit tweaking.
Not sure this link will work right, but what the hey:
http://neo.jpl.nasa.gov/cgi-bin/db_shm?sstr=2004+mn4&group=all&search=Search
> Those comets and asteroids have been awfully plentiful on our short life spans.
As they have in all human lifetimes. In fact, it certainly seems that impressive, naked-eye comets have been in short supply for a few generations. I've only seen one or two naked-eye, and I would've missed both had I not known to look for them. Whereas the 1910 approach of Halleys Comet lit up the sky, as did many previous comets. The sky seems to have been rather quiet of late.
Don't you mean:
Gobel warming?
Bleh. I hope it lands on Saudi Arabia.
Well, according to the calculator, nothing major happens on a global scale. The collision would be survivable by many in a city.
This is accounting for a 1,000 ft IRON meteor coming in at 50 degrees (most likely is 45) hitting ANY area.
Why are we worried now?
Gawd no, then they'll have another one to worship.
Observations:
This one is about 1000 times the mass of the one that formed the big crater in Arizona.
1/10th the Earth-Moon distance is VERY close.
The perturbing effect of a near Earth pass-by on the asteroid's orbit will have an unpredictable effect on the path of its future orbits, and when something unuusually close is given a randomizing change, the odds are vastly in favor of a change moving it farther away.
WEEEEESA GONNA DIIIIEEEE!!!
}:-)4
Gravity is a function of mass, and SUV's have mass, therefore if we ban SUV's we're safe, right?
Nothing to worry about.
The Mullahs already predicted that America is going to end in 2007, and some Inca calendar ends in 2012, proving, therefore, that the world will end long before the asteroid returns from its 2029 close encounter.
Therefore, be of good cheer. The asteroid can't hit us. We'll be dead already.
I would think the answer is obvious...destroy it in 2029 when it is only 25,000 miles away. Anything that remains will be too small to cause any problems on the second pass in 2034 or later. That gives us 24 years to think of a way to do it.
Heck, the people on Jupiter did the same thing to the Shoemaker-Levi comet. Broke it up into smaller harmless pieces so it wouldn't slam into their planet on the second pass.
Although, to be fair, I believe they had help from the Galactic Council and were provided plans for a giant Sonic Atom Smasher to do the job.
bump to myself. This is a classic FReeper thread if I ever saw one. Of course, we'll all be dead of Avian Flu or Marburg before any asteroids cleanse the planet.
I believe a half kilometer width object is assessed as significant enough to alter life on earth as we know it. I believ a half-KM width is the bar for tracking efforts now in place.
I think I read that a KM(kilometer)-wide object impacting earth is assessed as civilization ending (ie, extinction or close to it).
Check out 1999 AN's planned visit in 2044.
http://www.iac.es/galeria/mrk/1999an10_eng.html
http://neo.jpl.nasa.gov/news/news018.html
This page has some information but I truly do not expect it to contain the entire scuttlebutt. I do not expect the public to be informed or warned of what the government may know or expect to be the truth, especially in such a lengthy outyear. The USG/Brit Govt got a lot more proactive on NEO programs in the late 1990's...check out the "Eros" mission...timing and explanation of why.
I believe in mid-late 1990's perhaps we had a near-miss after the fact, that caught everyone by surprise. Maybe, as 2027 approaches, we can expect some more feel-good movies from Hollywood, like "Deep Impact", to reassure people that "the big one" will miss us or we will survive it.
So just keep paying the mortgage and credit card bills, for now. Maybe 40-year mortgages are not such a bad idea!
A couple more sites I bookmarked some time back.
http://impact.arc.nasa.gov/
http://cfa-www.harvard.edu/iau/NEO/TheNEOPage.html
I posted a link to an impact calaulator in reply #50. A 1000 ft Dia iron asteroid would not provide any global scale problems.
I refuse to even think about going around thinking like that.
Gives new meaning to "Friday the 13th."
This could be the answer to our social security problem.
Only prob with all of that is that this is a 1/3rd KM object. much smaller.
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