At http://phys.org/print300699048.html … Finnish scientists in collaboration with the Russians have been looking at the Chelyabinsk meteorite that exploded over Russia in February. This was he largest cosmic object entering the atmosphere since Tunguska in 1908 – it is believed. The asteroid was just 20m in diameter but managed to release energy equivalent to 440 kilo tons of TNT and apparently, we are told, asteroids such as this collide with Earth every 100 years. Who did the arithmetic I wonder as the maths is missing. Are they just averaging two events? It disintegrated high in the atmosphere – its saving grace. Not a lot of substance is given away.
At http://phys.org/print300699447.html … Comet ISON has a dust coma that is red – but not as red near the nucleus. Only one side of the comet nucleus is showing signs of responding to the presence of the Sun. It is thought it is the heat of the Sun that causes the comet to brighten – by shedding dust and ice particles. In EU theory an electroc magnetic effect is involved – rather than heat. It is expected by all concerned to become brighter as it gets close to the Sun.
At http://phys.org/print300698735.html … will Comet ISON survive its orbit around the Sun to wing its way out of the inner solar system ?