Comet 20013 A1 (Siding Spring) to obliterate Mars' atmosphere in October 20th 2014.
Youtuber BPEarthWatch's mission seems to be to pre-empt the End Times i.e. religious fever for DOOM. This urge motivates BPEarthWatch to look into all sorts of doomy news, weather and space events and ratchet up the paranoia and fear for THE END IS NIGH; you know BME or Biblical Magnitude Events.
Plus, I really like his laid-back delivery in the face of his maker's potential for ultimate horror i.e. the universe we all live in.
FEB 12TH UPDATE: here's a little more information concerning Comet Siding Spring.
Michal Sadlon of INOVE sent through a link to a 3D-visualisation his team's been working on - very sexy, very illustrative.