The image below is an up to date map of the solar system displaying the orbits of the terrestrial planets, and the estimated position of thousands of known asteroids. This diagram is missing comets, space probes and of course the undiscovered asteroids, even conservative estimates would suggest that for every asteroid on a dangerous Earth-Approaching orbit there are hundreds more which have yet to be discovered. There are over 300 known objects on Earth-crossing orbits, the majority of which are potentially capable of causing death and destruction on a scale unheard of in human history.
The terrestrial planets (Mercury, Venus, Earth and Mars) are shown on the diagram by Cyan or White squares, and their orbits are represented by the blue ellipses around the sun (the yellow dot at the centre). The Earth is highlighted because of it's special importance to us.
Small green points mark the location of asteroids which do not approach close to the Earth right now; this does not preclude the possibility that they won't in the Future, but generally we can consider the Earth to be safe from these for the near future. Yellow objects (with the exception of the one in the middle, the Sun) are Earth Approaching asteroids - named Amors after the first one discovered - Amors have orbits which come close to the Earth but they don't cross the Earth's orbit. However their orbits are close enough to the earth that they could potentially be perturbed by the influence of the planets and begin to cross the Earth's orbit in a short time. There are over 250 objects classified on such orbits
Finally the Red boxes mark the location of the Apollo and Aten asteroids, these cross the Earth's orbit, and are the most directly identifiable astronomical threat for the near future. Included in this selection is the Infamous asteroid 1997XF11 which made a major impact on the World's headlines in March 1997 when observations indicated that It had a good chance of colliding with the Earth in 2028. Thankfully, new observations were made and the newly calculated orbit predicts a close approach of about 600,000 kilometres.
It is estimated that there are perhaps 100,000 to 1000,000 undiscovered asteroids on similar Earth crossing orbits.
Have a Nice Day. Looks like whatever we do to this planet to fuck it up ourselves, we're fucked eventually anyway.
http://www.carleton.ca/~tpatters/tea...s/neostorm.gif |
