How much notice would we have if an astoroid was going to hit earth?

Question

maybe a good website referall cause both of the first two answers didnt even attemt to give me a real answer

Answer 1

At least 5 millon miles or more, time frame would be how fast its moving.

Answer 2

If it is a known asteroid and its orbit has been determined, then we should have plenty of notice.  However, it is estimated that up to 90 percent of the Near-Earth Objects associated with asteroids are known.  That means about 10 percent of these asteroids that are expected to make a close encounter with the Earth's obit has not been spotted yet.  These asteroids will fall to a group of sky watchers who monitor the sky for these types of objects.  Those 10 percents is what concerns most people in the field of science.  And the amount of warning will depend on how early they can spot the object and to correctly determine its obit.  There is a chance one may not be spotted by one of these teams and there will be little advance notice.  

For more information, here are a few links that may help you answer this question.

NASA and international Near-Earth Object watch program.

http://neo.jpl.nasa.gov/programs/

NASA links on this topic

http://neo.jpl.nasa.gov/links/

Studies done by NASA

http://impact.arc.nasa.gov/gov_nasastudi...

Studies done in the UK

http://impact.arc.nasa.gov/gov_UK.cfm

NASA report to congress 1998

http://impact.arc.nasa.gov/gov_asteroidp...

Answer 3

Not much at all if any... if your luck is like mine you'll be in a meeting with the governor or on hold with the cable company when it goes south.

Answer 4

I would greatly depend on the size and direction it was coming from. The people, according to "Megadisasters" program that look for these things, fear having one come around the sun and in from that direction. They fear our telescopes would be blinded by the sun.

Large bodies of course can be seen much farther than smaller ones. In some cases they have seen them hours before closest approach, other times weeks.

Answer 5

Usually these things just don't sneak up on us.  Usually scientists are tracking these things for months or even years.    We are also trying to get missle defenses together that may help in that evenutality but I can't tell you how close we are to doing that.

Answer 6

well, if a small asteroid hits your house, sell it. youll have millions of dollars for you to buy textbooks about this and reaserch of how much notice.

Answer 7

depends on when it's discovered

you can only know in about roughly a year.

Answer 8

not too much because satellites around Earth would have a moment's notice to react