The asteroid is called 2012 BX34 and measures roughly 11 meters in diameter. It did cause a few astonomers concern when it was initially discovered. Observers thought BX34 would pass much closer to Earth at around 20,000km, but the predictions were off and we are not going to lose any satellites. A collision with Earth definitely won’t happen so we can all relax.
If you’re trying to visualize how big an 11 meter wide asteroid is, the BBC refer to it as about the same size as a double-decker bus:
Even so, when it passes by at around 11am EST (4pm GMT), you won’t be able to look up and see it with the naked eye. However, if you’re an amateur astronomer with a decent telescope set up, you could catch a glimpse of it speeding past.
Gareth Williams of the Minor Planet Center has some further reassurance for us. A bus-sized asteroid may sound huge, but in the grand scheme of things it is relatively tiny, and even if it did have a course that saw it travel into our atmosphere, it would most likely break up into smaller pieces.