Asteroid 2015 SZ2 Close Encounter with Earth Sept. 30, 2015

a reply to: Milah

interesting url

http:/www.express... End-of-the-world-asteroid-Blood-Moon-September-apocalypse-armageddon-comet-meteor

and all this in the science directory.

When scientists predict perihelion and CPA of comets and asteroids, it requires a number of good positional fixes to get an accurate orbit. The extremely accurate software which they use, also takes into account the moving Earth and the gravity and orbit of anything substantial near the object. This usually puts the standard deviation that they are correct in the 99.7% probability, or 3 standard deviations for reasonably circular orbits. Elliptical Orbits are more difficult, and take more time, but in these they push the sample frequency to try to get to a 3 sigma confidence. As the object gets close to the estimated CPA, the final fixes usually push the confidence level to 4 sigma (99.994%)

Why say all that? Well consider an NEO that has been cataloged as above, and it is .01 lunar distance CPA. That is 2,500 miles away from the Earth, with Earth/Moon motion and gravity factored in as well. Even at a close distance like this, it would take an enormous force to push that object toward Earth. It would have to be hit by another object to cause such an anomaly.

Scares are not warranted unless an object is really headed for the Earth, in which the same mathematics would provide that analysis as well. Science should be trusted in this regard, and not ignored.

Here one that just miss us on Sept 22 2015

On September 22nd 21:44 UTC, an 8 metre sized Apollo NEO dubbed 2015 SK7 made a close approach of our planet at 0.068 of a Lunar Distance. (26,241 Km)

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