Last Updated: Thursday, August 02, 2012, 16:21
Supernovae can occur at the end of a massive star`s lifetime when its nuclear fuel is exhausted and gravity causes it to collapse on itself.
Last Updated: Sunday, July 10, 2011, 16:51
The blue coloured eighth planet of the solar system, will this year complete its first revolution of the sun since its discovery in 1846.
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