Do we need to be worried about the asteroid impact.?
489309
No need to, can't do anything about it.
534145
Probably.  Meteorites hit the moon every hour of every day.  Will an astroid large enough to be detected hit the moon and cause turmoil on Earth?  No.
863906
There is actually a website about that, that shows you how close they come, i don't remember it off-hand though.  it's pretty neat though, you can like fast forward in time, and reverse.\n\nEven if an Asteroid was going to hit the earth, whomever spotted it wouldn't tell anyone, would cause too much commotion.\n\nHere is a pretty cool site I just found about it, it says 1 in 40 chance in 2029 \nhttp://www.space.com/scienceastronomy/asteroid_update_041227.html
364727
Nope...The sun still has plenty of hydrogen, and the only Earth smashing asteroid that we know of is still over 800 years away. Everybody Party!!
463009
They realise they should have turned right at Warsaw.\n\nSeriously, it would result in enormous climate changes, tectonic plates could be affected resulting in earthquakes, harmful radiation from the sun could seep through - the Earths magnetic field behaves like a shield, hence the northern lights. \n\nPolarity changes have happened before on Earth and scientists believe we are overdue for another one.\n\nSo, something else to add to the list of 'Armageddons' we seem to have stacking up against us. No point worrying really, if one catastrophe doesn't get you, then another one will!
1089400
It seems very possible that asteroids seeded this planet with life. That might have not been as accidental as some people think.
195527
Well, without the moon, we'd have almost no tides, which could present its own set of problems. Given that a lot of our weather can be ultimately relatable to tidal action, this could be potentiall disasterous, even if no fragments ever hit earth.\n\nAlmost everyone's answer concerns an extinction level event on earth, and that's not necessarily true. The earth is not a static point around which the moon rotates. Rather, due to the fact that the moon is an appreciable fractional size of the earth, the 2 combine in its revolution around the sun around a mutual center of gravity called a barycenter. Without the moon, the earth's revolution would be subject to some variation given the fact that now only the sun's gravity is affecting the earth.\n\nThe moon does rotate around the earth however; it's not just sitting there in space. Depending on the angle of impact of an incoming planetoid (at the size of the moon, asteroid would be rather small), not every impact would cause an extinction event on earth. For example, if an incoming planetoid impacted from an angle where the planetoid cuts between the orbital paths of the earth and the moon, the impact would cause the debris to enter an elliptical orbit, rather than a circular one, around the earth. It would remain to be seen if said orbit would be dangerous.\n\nIf the planetoid hit the moon from behind AND tangential to the moons orbit, very few of the fragments would actually impact the earth. The debris would continue in the original orbit, but accelerated based off the original velocity of the planetoid. This would decrease the period of revolution around the earth for the remaining debris.\n\nWhat everyone else is describing is where the planetoid would approach from outside the E/M system that would cause such huge devestation on earth. Or, if the planetoid hit the moon headon, causing a slowing of the moons orbital rate by the velocity of the incoming planetoid.\n\n"Freezing at night" is not a valid outcome; the moon shines light on us; it doesn't radiate heat. "Tidal waves" are really related to underwater earthquakes, not actual tidal action by the moon (think about it; every place on the coast experiences high and low tides 2x every 24hrs 34 minutes; if the moon created "tidal waves" every seacoast would be innundated horribly, and without the use of hurricanes!). Electric bills, as someone put, would remain the same (think about it; if it's dark outside, you turn on the lights, regardless of whether or not it's a full moon). Crime rates would probably go up a little in the outlying areas (where there is less artificial illumination to begin with), but not as horribly as someone described.\n\nJust remember: not all impacts would be bad. ;-)
478432
First: we are constantly being bombarded by millions of asteroids. The only thing that saves us is the atmosphere, which vaporizes them.\n\nI'll do a little math. We'll consider the solar system to end after the Oort Cloud, 100,000 AU or 9,300,000,000,000 miles. Therefore, the solar system has a volume of 4/3*π*(9.3*10^12)^3, or ........ about 3.369*10^39 cubic miles. The Earth has a volume of about 2.08*10^12 cubic miles.\n\nIn short, the Earth takes up 0.00000000000000000000000006% of the solar system. Even with trillions of potential threats, the chances are next to nothing.
729001
LMAO.\n\nAnd we should be worried about this?  Why?\n\nHave a nice day.
250469
i agree debris would be the larger problem in the near future.\nIts all about time scale and which two planets, it might not affect our lifetime. On the other hand our neighborhood as become pretty calm and not so much traffic as when the planets were forming, I suspect it will only get calmer and more boring unless the sun does some crazy stuff.
116610
cute_blondie_angel is correct, although the impact was likely a comet and not an asteroid as there is no impact crater.
592550
earth is a living thing man, it is still not stable, but you have to look at it in time frames... we've only been here for so long.. it was stable for the dinousaurs for a while.. at least before it got hit with a comet, it had to go back and fix itself
517283
That is the BIG question!  When will it happen?  No one knows and there are only guesses.  Some believe it will not happen as a one big one because the Bible foretells us that it one hundred pound rocks will fall from the sky.  Scientist say we are past due for a big one to hit because the earth was hit so many millions of years ago. \n\nI do not think sitting around and worrying about it will be a productive and worthy of our attention.  When it happens it will happen.  The chance of it happening in our life-time (compared to the millions of years since the last one) is so small that it is not worth computing.  \n\nWe have plenty of people being dooms-day prophets, we need to be more optimistic and looking for how we can improve each others lives for the here and now.
688079
No, if you think about it-*your* death is all that would matter to you at the time of death- If an asteroid wiped out the Earth, then the consequences for you would be no more than the much much more likely event of you dying in a car accident, or of a fatal stroke. Unless you have some altruistic worry about humankind in general, being killed by an asteroid and being killed by choking on a chicken bone is pretty much the same thing.  Of course, and normal person loves their family and freinds-but again, they are much more likely to die of disease or in a car accident-in addition, there is absolutely nothing you could do about an asteroid, so best to spend any worry energy on common means of death (accident, disease) and preventing that in you and the ones you love, than about low-probability things that you cannot effect.
871527
First off, as others have said, the physics of Apophis are well known now.  At the time, however, the asteriod was too far away to get the accurate measurements needed to determine it's trajectory.  But within a couple of days they DID get the measurements.  No, Apophis will not hit in 2029.  There is a miniscule chance (1:45000) it may hit in 2036, but we'll know decades before and there IS something we can do about it.  On the flip side, there will be a day when Apophis will hit us if we do nothing.  It's only a matter of time.\n\nIf, however, the Earth was going to go and there wasn't a thing that could be done about it, who would want to know?  Civilization would disintegrate - no one would go to work crime would be rampant, and things would be horrific long before the asteroid hit.  No government would tell us.  \n\nPersonally, I wouldn't want to know my family was going to die without any hope.
563193
From what I understand for a specific asteroid they can extrapolate its orbit from what they have observed so far while taking into account the uncertainity in their estimates (because of not enough time spent observing it for example) and see what probability it has of impacting the Earth.  What has happened with every potential Earth impactor we've found is that as the object was observed more closely and the uncertainities vanished the probability of Earth impact went to zero.\n\nIf OTOH you want to know the probability that an asteroid, not just a specific asteroid that is being observed will hit the Earth then you've got to make some assumptions.  First you have to assume how many asteroids of each size there are that cross the Earth's orbit and those assumptions are being changed as more observations come in.  Then you can calculate the probability of one of them hitting the Earth and how long on average between impacts (I'm not sure the actual steps of the calculation, you might have to check some journal articles on it but it'd probably be pretty tough going if you don't have a good grounding in maths and physics and if you haven't read a journal article before you probably won't want to).\n\nWith large asteroids the asteroid watchers seems to be pretty confident that all the big ones that we'd have plenty of warning if a big one were on its way so the small ones that might only wipe out a city or the comets that come from nowhere at much higher speed worries right now.
376755
Nope, nothing that we have found will be coming very near us on that date.  Just to give an update on the object the Braxton_Paul mentioned, 2004MN4 (now designated 99942 Apophis), has pretty much been put into the clear for the close approach in 2029.  It will come close, but unless something funny happens to the orbit (collision, unexpected outgassing phase etc), it will miss us.\n\nWhat we are trying to get a fix on now is the next close pass by this bad-boy: 2036.  We can't rule out an impact probablitity for that encounter yet.