Why didn't anyone see the meteor that fell in Russia? [video]

You must be tired of hearing about the famous meteor that crashed in Russia two weeks ago, right? Since then we have learned that it is ordinary chondrite - the most common form of space rock - that the gram of fragments can be sold for 40 times higher than gold, and that its entry in the atmosphere caused a sonic explosion equivalent to 30 atomic bombs like Hiroshima's.

But have you ever stopped to think that despite so many satellites, radars, observatories, and space telescopes aimed at space, no one saw such an object approaching? What's worse, the whole planet was alert, as the day after its impact on Russia, asteroid 2012 DA14 would be grazing over here on Earth!

So how did no one detect the approach of the meteor that hit Russia? According to NASA, what happened was that the meteor came from the same direction as the sun, being hidden from the "view" of all equipment. And to further clarify this mystery, the space agency even decided to produce the video above, which explains very well why the arrival of the space rock went unnoticed.

The video is English, but the Portuguese subtitles - which you can enable in the menu itself - are quite understandable.