How many NEOs (near Earth objects) could hit us?
369372
We are currently observing 7 objects with a small possibility of hitting us in the near future, and keeping tabs on 14 others that we can't see right now (the sun is in the way).  We also know of 26 objects which we have "lost," but feel that it would be a good idea to find again, just in case.  We also know of another 33 objects that could potentially hit us, but are rather small and would only cause minimal surface damage.\n\nAll in all there are a quite a number of potential impactors right now, we're watching them closly to see if any really will hit us or not.  Obviously this does not count really small things that hit us all the time, just things that are large enough to see in moderate sized telescopes.\n\nJust noticed the source link below mine -- nice to see that Yeomans and Baalke got the JPL site working and up to date again!
1117857
Ok there are no known meteors that are going to "kill all Earth's life", and I highly doubt you'll be the one to find them while the highly trained astronomers do not. You'll need a very large opening (lens, the big opening at the top) to find meteors that far away. Power (magnification) is not important when the opening is very small. I'm sure you're asking this because of a meteor that is supposedly passing by on the 3rd at the 12th magnitude (you'll need a very good telescope and you can't see it with the naked eye).
1035178
If I'm not mistaken, we've tested a number of 20-megaton nukes before, and the fact that you're able to ask this question means that we've survived that first test. :-)  \n\nAs for how big of a nuke it would take to blow up Earth, a couple of issues you'll have to deal with first is what to do about all of the debris that will settle after the nuke goes off, because as it floats back down because of gravity, then gravity itself will hold down all of the matter upon Earth. As to what it would take to cause the most damage, I've gotten to thinking since the 2004 tsunami that if a well-placed nuke was right on major fault lines either in the ocean or possibly on land (like maybe on the New Madrid fault), the tectonic action resulting from the force of the nuclear blast would be much more destructive than the bomb itself, because the shifting of tectonic plates would then cause damage at a much greater radius from ground zero in the resulting earthquake than would just blast waves in an atmospheric explosion.\n\nMaybe that doesn't answer your question, but it's the best I can figure as I am neither a physicist nor a geologist. :-)
148286
The earth DOES go through an arm of the asteroid belt that extends very close to earth's orbital path that's why we get spectacular metior showers every november.  \n\nnow that that is out of the way.\n\n  yes sometimes satelites and or the spacestation do get hit.  in fact they are more often getting hit than not.  they are under nearly constant bombardment however like was earlier said most of what hits them is smaller than grains of sand.  if they were to get hit by something largish though depending on where it hit exactly and how it is very likely that it would cause MAJOR damage.  ultimately resulting in the satelites decaying orbit and eventuall reentry.  this sort of thing happens all the time.  personally i'm waiting for hubble to take a right good one right in that pretty little mirror it's got.  that will be one great big and expensive I TOLD YOU SO!\n\nas for the space stasion.  some of its components are like 15 years old.  most of us don't even have cars that old.  we are talking potential for irreparable damage and Cascade FAILURE. any # of things could happen including but not limited to Explosive Decompression.
1020350
You might be talking about a star designated as HR8210. It's 150 light years away from us, and the estimated minimum safe distance for Earth to be relatively safe from a supernova explosion is 160- to 200 light years. HR8210 is the closest supernova danger, but it should be many millions of years before it blasts.\n\nThis website has lots more info about HR8210 --> http://www.aad.gov.au/default.asp?casid=6283
586535
A continuing effort to identify even near Earth asteroids which are relatively easy to track and have a greater possibility of collision is still incomplete, with only a fraction of their orbits plotted. Since the orbital periods of comets and other Oort cloud entities are in the tens, hundreds, or even thousands of years, many of these objects have never been seen in recorded history, much less their orbits calculated and possibility of collision with Earth evaluated. With this in mind, an event such as this might be possible at any point in the future, although since objects from the outer solar system tend to be rather reflective, chances are that they would be spotted and we would have some advance warning of a likely intersection with Earth orbit presenting a cause for concern. That said, the chance of it happening in any particular year is extremely remote, the likelihood of it happening sometime in the next several million years greater.
1126158
There are almost 25,000 man-made objects: 8681 currently in orbit, and over 16,000 objects in a state of decay. Not every single satellite is included, since some are too small or too far away from home to be detected.
674694
Meteors aren't the worry, it is asteroids.\n\nAsteroid Toutatis is about 2.9 miles long and 1.5 miles wide (4.6 by 2.4 kilometers).\n\nOn September 29, 2004 Toutatis was within a million miles of Earth, or about four times the distance to the Moon.\n\nOther, smaller asteroids have come closer than that.
1006449
Space detritus misses us constantly.  There's a near miss every 3 weeks or so (on average).  Thing is, the universe is mercifully large, and what is deemed CLOSE is close in terms of the size of our galaxy, but the odds of us being actually struck are low.  \n\nInteresting fact:  Hailey's Comet it supposedly going to finish it's fall in Iowa, some 3 million years from now.  Watch out!
810232
It is estimated that Earth is bombarded by a city-sized asteroid once every 65mil yrs.\ni) Assuming a Poisson distribution, find the probability that Earth will be hit by 2 or less of such asteroids in the next 10000yrs.\nEta Carinae is a suspected hypernova that is 7000 light-years away from Earth. Scientists have observed 200 of such star in many distant galaxies. It was found that the stars have an average life-span of 200mil years with variance 2500mil yrs^2.\nii) Construct a 95% confidence interval for the mean lifespan of Eta Carinae, giving your answer correct to 8 significant figures.\nIt was found later that Eta Carinae was formed 200.01mil yrs ago. \niii) Using the sample of 200 stars earlier, a scientist boldly claimed that Eta Carinae will explode today, causing devastation to Earth in 7000years’ time. By stating clearly the null and alternate hypothesis, test the scientist's claim at 5% level of significance.\nYou may assume the normality of the population of stars observed.
1185571
a meteor is going to pass very close to the earth on that day...check out\nhttp://english.ohmynews.com/articleview/article_view.asp?at_code=341846
932550
the article from 40 years ago must have been wrong, or more likely more accurate observations revealed that the asteroid posed no danger to earth. The only asteroid that "MIGHT" hit the earth that is known of is the asteroid discovered in 2004 and named Apophis. it will come very close to earth in 2029, so close that it might be pulled into an orbit that will hit the earth on its next approach in 2036\n\nhowever we will not know for sure until we get more accurate measurements of its orbit, probably not till its approach in 2029.\n\nSo don't worry about it, by then we should be able to deflect it, if it indeed will be on a collision course.
805597
Since astronomical equipment that monitors the sky will pick up NEOs in the process of general monitoring, there is little cost involved.  Even the few deliberate searches are inexpensive.  Think of it as insurance.  Even if a million dollars a year is spent (the actual figure is FAR less) on searching for NEOs, if one similar to the Chicxulub impact were heading our way, the cost of the impact would be close to infinite, since it would eliminate any possibility of human civilization and come close to exterminating the species.  If we detect one early enough (ten years or more at this point), we can manage to deflect or destroy it.
395085
yeh, a meteorit and a galaxy are coming to earth. Don't worry, they come only after 2 milion years...;))
1155981
it wont be here.....2036 theres an asteroid set to collide with earth the size of Texas...heard it on APNews
400469
http://www.cnn.com/TECH/space/9907/28/asteroid.newser/
26852
The asteroid belt is a very large volume of space.  From any one asteroid, the next nearest (known) asteroid is typically a million miles away.  So you're really not likely to hit anything, unless there are lot more asteroids than the known ones.