What are the chances of an asteroid hitting our planet?

Question

Anyone out there that studies science know just how safe we are from getting hit with any large asteroids?

Answer 1

100%

And in a few years there is a 1% chance that Apophis will hit us. It is an asteroid on course to come near the earth. It will come so near that it will be closer to the Earth than some of our satellites.

Gene Shoemaker has been telling scientists for years that the Earth is in a huge danger from stray asteroids and comets. Just look at the moon! For a long time scientists thought the moon had active volcanoes in the past, but all those craters are now known to be caused by meteors. I heard a quote on the History Channel that the earth gets hit by a small asteroid chunk about once every 4 hours. These are chunks of rock that survive burning up in the atmosphere and actually hitting the earth. There are a lot more that get burned up and never reach us; like next week’s Perseid Meteor shower (an annual event).

Arthur C. Clarke, an astronomer and science fiction author has been worried about asteroid collisions long before we knew about the dinosaur killing asteroid collision. He inspired people like Shoemaker and Levy who are amateur astronomers who search for NEOs (Near Earth orbit Objects). NASA is working on plans to do something if we find one on a course for earth. They have found that if you tired to blow one up with a nuclear bomb it would take a few million megatons or gigatons. No nation would allow someone to put a nuclear bomb that big into orbit. So we need other ways.

A former astronaut has a plan to just put a spacecraft near one and let it sit there. The gravity from the spacecraft would be just enough to nudge the asteroid on a different course so it will barely miss the earth. But, his ideas haven’t even left the drawing board yet.

If Apophis enters a narrow course window, as it passes us in 2026, then it will pass by the earth and swing around and in the year 2036 it will hit the earth.

The sooner you catch the asteroid the easier it is to nudge it off course. Some plans for doing this are to use a huge rocket, or to use a huge mirror to let the pressure of light move the threat away from us. The problem is that we don’t notice most comets until they have already crossed our orbit and are glowing from being so close to the sun. That’s why it is crucial to keep track of them and to search for any new ones.

We can thank and blame Jupiter for these asteroid and comet threats. The gravity of Jupiter is so strong that it can reach out beyond the orbit of Uranus to the Kiper Belt and pull asteroids and comets into the inner solar system. But as Comet Shoemaker-Levy 9 proved Jupiter also sucks up a lot of those asteroids and comets. CL-9 was broken up before it hit Jupiter, but it still hit the planet with the power of a few dozen atomic bombs. If just one of those large pieces had hit the earth we would have gone the way of the dinosaur and the dodo.

A comet or asteroid could hit us tomorrow and so few people are trying to do anything about it that it is scary. The danger is real and I need people like you to start working on possible solutions for it.

Answer 2

Apophis is about 350 meters long, not 2,000. Moreover, in order for it to strike the Earth on April 13, 2036, Apophis has to go through a region of space some 600 meters wide on April 13, 2029. The chances of this happening are very slim, but not impossible. If it does strike, it will be the deadliest natural disaster during recorded history, but we have time to either alter it's orbit or at least prepare for the worst. It will not exterminate us off the face of the Earth, instead it will cause total destruction locally or regionally depending on where it strikes, if it strikes at all. Even if it's proven to be on an collision course with Earth, we have time to study the asteroid and take appropriate action. A 2,000 meter long asteroid on the other hand can wipe the human race out for good, especially if it hits the ocean. It will make a massive crater regardless of where it strikes because at 50,000 mph the asteroid will sweep even several miles of sea water aside and plow into the sea floor. The resulting mega-tsunamis, earthquakes, nuclear winter and white hot debris falling all over the world will devastate the enviroment on a scale that will exceed a global nuclear war many times over. If we found one of those on an course that will end in an impact within a year or even 20 years, I doubt we can do anything to stop it. We could be blindsided by a 2,000 meter long asteroid at any time, which is why professional astronomers with the help of amateurs are doing their best to keep close watch for these bringers of death and track their movements. The most dangerous objects are the Aten class asteroids and comets. Both can come our way out of the glare of the Sun, they are hard to see and their orbits are especially unstable and hard to track over time. You have some erroneous information, because although Apophis IS potentially hazardous, an impact with Earth is not imminent. It is of concern, make no mistake about it. But it's not nearly as dangerous as the ones that are out there undetected and on unknown trajectories, one of which that could bring one to Earth with little or no warning.

Answer 3

To view estimated probabilities that particular known objects will strike the Earth in the future you should look at the JPL NEO Risk Pages or the NEODys risk pages, see links below.

At present, (99942) Apophis' chances of hitting us are put at around 1 in 45,000. It will come quite close to the Earth on April 13, 2029 (and yes it is a Friday), about 38,000 km at closest approach (about 1/10th the distance to the Moon.) If it passes through a particular region of space at the right time during that pass its trajectory will be altered such that it will strike the Earth in 2036. The region of space is only about 600 m in size but our present knowledge of Apophis' orbit leads to a position uncertainty of around 500 km when propagated to 2029. However the particular "keyhole" region is some distance away from the central estimate of the trajectory so even increasing our knowledge of the orbit to the point where the uncertainty at 2029 is 100 km may be enough to know for certain that Apophis will not pass through the keyhole.

At a wider level, small asteroids hit us all the time. Researcher Peter Brown from Canada and co-workers published a paper in Nature in 2002 estimating that the Earth gets hit about once a year by an object about 4 meters in diameter. There may be as many as 1 billion such objects with perihelia less than 1.3 AU. We don't really notice these. There may be several hundred thousand to 1 million objects as large as that which caused the Great Siberian Explosion near the Tunguska River in 1908 with perihelia less than 1.3 AU. The recent NASA report estimated around 100,000 objects larger than 100 meters in diameter with perihelia less than 1.3 AU and around 20,000 of those that could come within 20 lunar distances (7.5 million km) of the Earth. It is also estimated that there are about 1,100 objects larger than 1 km in diameter with perihelia less than 1.3 AU. We presently know of about 700-800 such objects, most discovered through NEO survey projects.

Answer 4

It is a 100 percent certainty that we will be hit from time to time. We are not at all "safe." We just have no way of predicting when it will happen.

So find love...

Answer 5

100 %
anytime it could happen, so tell the people you love that you love them, before the end of the world

Answer 6

100%

in fact several already have.

Answer 7

100%

but not today...