Asteroid Collision 2012
Will there be an asteroid collision in 2012? Will a giant meteor bring about the end of the world on December 21, 2012? We've put this page on asteroids, comets and meteorites together to answer that question. In describing any potential asteroid collision with earth, we've tried not to get too technical. We think you will find this page helpful. Short answer, there will be no catastrophic 2012 end of the world asteroid collision on December 21. Read on and find out why we don't need to fear any giant asteroid in 2012.
NEO's - Asteroids, Comets and Meteorites
Comets (made up mainly of water, ice and dust) and asteroids (of more solid composition) that come near earth are called Near Earth Objects (NEOs). But just because they come near earth it does not mean that the earth is under any kind of threat or even the threat of extinction. Many objects pass earth all the time and there is no danger to us. Even some that come close do not threaten earth because their size is so small.
The threat which NEO’s could cause is listed on what is called the Torino Scale and it ranges from a remote chance of local destruction (basically, where the object lands) from a bus sized object hitting earth to a certain collision from an object that is capable of causing global climatic catastrophe and would threaten the future of civilization as we know it. This threat would exist whether the object landed on the earth or in the sea.
NEO’s are constantly monitored by scientists to determine their possible threat to earth; what kind of damage might be caused if there was an asteroid or comet strike on earth. Scientists look at size, shape, mass, composition and structure of NEO’s to decide the best way to redirect one should it come dangerously close to earth.
The Hubble telescope (see image below) orbits 353 miles (569 km) above the Earth. From there is has a clear view of objects deep into outer space, free of any of the earth's atmospheric disturbances.
The difference between Asteroids, Meteors etc.Asteroid
An asteroid is a relatively small, inactive, rocky body orbiting the Sun. "small" can be up to many kilometers but it is small in comparison to the sun. When an asteroid enters the atmosphere of another heavenly body (eg. earth), it is called a Meteor. It could be small or it could be a giant meteor. Comet
A comet is a relatively small, at times active, object whose ices can vaporize in sunlight forming an atmosphere (coma) of dust and gas and, sometimes, a tail of dust and/or gas.Meteoroid
A meteoroid small particle from a comet or asteroid orbiting the Sun. Called a meteoroid when it is still out side our atmosphere. Meteor
A meteor is the light phenomena which results when a meteoroid enters the Earth's atmosphere and vaporizes; a shooting star.Meteorite
A meteoroid that survives its passage through the Earth's atmosphere and lands upon the Earth's surface.
Actual Asteroid / Comet Collisions
- Earth is bombarded with over 100 tons of dust and sand sized particles every day.
- About once a year a car sized object enters the earth’s atmosphere but burns up on entry.
- About every two thousand years, a large football sized meteoroid strikes the earth causing significant damage in the area where it lands.
These first three types of collision are observable and we know they happen. There is a fourth type which those who believe the earth is billions of years old also believe happens. They believe that once every million years or so, an object large enough to threaten earth’s civilization comes along. The extinction of the dinosaurs has been blamed on a large asteroid hitting earth. However, the evidence does not support it. Large dinosaur fossil graveyards are evidence of a sudden burial by water deposited minerals that could only have been caused by a worldwide flood. The only way the bones could have been preserved so well for so long is if they were buried quickly. Different cultures all over the world have stories and drawings depicting a worldwide flood…. But, back to asteroids, and a possible collision with the earth.
Asteroid Size and Damage
Space rocks smaller than 25 meters would probably burn up on entry
- An object 25 meters to 1 kilometer would cause local to regional damage
- Anything larger than 1-2 kilometers would have worldwide effects
Potential Asteroid Threats
Many will have heard of the asteroid Apophis which will pass close to the earth in 2029. It is not currently listed as a threat to earth by NASA.
The largest known threat anywhere near 2012 is an asteroid called Toutatis which is 4.6 x 2.4 kilometers. The orbit of Toutatis, which brings it close to earth every four years, goes from just inside the Earth's orbit to the main asteroid belt between Jupiter and Mars. Asteroids in this asteroid belt have been measured to be as big as 940 kilometers across but because of their orbit and location are no threat to the earth. In November 9, 2008 Toutatis came as close as 7,510,000km to the earth. It’s next close pass at around 6,900,000km is expected on December 12, 2012. Toutatis also came close to the earth in 1996, 2000 and 2004. However, NASA rates the chances of Toutatis hitting earth as being essentially zero.
NASA has identified 982 PHA’s (potentially hazardous asteroids) and 65 PHC’s (potentially hazardous comets). A potentially hazardous object is one that makes close approaches to the earth and also is big enough that if it strikes could cause significant regional damage. NOTE: regional is nowhere near as big as global. A region could be a town or a city.
However while these have been identified as a potential danger because of size and closeness, NASA also said that there is a zero chance of any of these hitting earth. They also state that there is no known NEO’s on a collision path with earth. And while it is possible that there may be as yet an undiscovered NEO on a collision path, it is unlikely that this will happen in the next 100 years.
0 The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage.
1 A routine discovery in which a pass near the Earth is predicted that poses no unusual level of danger. Chance of collision is extremely unlikely with no cause for public attention or public concern.
Meriting Attention by Astronomers
2 A discovery, which may become routine with expanded searches, of an object making a somewhat close but not highly unusual pass near the Earth. While meriting attention by astronomers, there is no cause for public attention or public concern as an actual collision is very unlikely. New telescopic observations very likely will lead to re-assignment to Level 0.
3 A close encounter, meriting attention by astronomers. Current calculations give a 1% or greater chance of collision capable of localized destruction. Most likely, new telescopic observations will lead to re-assignment to Level 0. Attention by public and by public officials is merited if the encounter is less than a decade away.
4 A close encounter, meriting attention by astronomers. Current calculations give a 1% or greater chance of collision capable of regional devastation. Most likely, new telescopic observations will lead to re-assignment to Level 0. Attention by public and by public officials is merited if the encounter is less than a decade away.
5 A close encounter posing a serious, but still uncertain threat of regional devastation. Critical attention by astronomers is needed to determine conclusively whether or not a collision will occur. If the encounter is less than a decade away, governmental contingency planning may be warranted.
6 A close encounter by a large object posing a serious but still uncertain threat of a global catastrophe. Critical attention by astronomers is needed to determine conclusively whether or not a collision will occur. If the encounter is less than three decades away, governmental contingency planning may be warranted.
7 A very close encounter by a large object, which if occurring this century, poses an unprecedented but still uncertain threat of a global catastrophe. For such a threat in this century, international contingency planning is warranted, especially to determine urgently and conclusively whether or not a collision will occur.
8 A collision is certain, capable of causing localized destruction for an impact over land or possibly a tsunami if close offshore. Such events occur on average between once per 50 years and once per several 1000 years.
9 A collision is certain, capable of causing unprecedented regional devastation for a land impact or the threat of a major tsunami for an ocean impact. Such events occur on average between once per 10,000 years and once per 100,000 years.
10 A collision is certain, capable of causing global climatic catastrophe that may threaten the future of civilization as we know it, whether impacting land or ocean. Such events occur on average once per 100,000 years, or less often.
The main source of information on this page is from the following links....