Remember to duck this Friday!
As any one who has been following the news lately knows, a small asteroid named 2012 DA14 will make an especially close flyby of Earth later this week. The 50-meter wide (~150-foot) asteroid will pass within 27,700 km (22,200 miles) of the Earth’s surface at 19:24 UT on February 15. At that time the asteroid will be over the Indian Ocean.
This is the closest known approach of an asteroid of this size. Such an occurrence should happen once every 40 years, on average. The reason this is the first detected close approach of its kind is because we only possessed the technology to easily discover such object over the past 10-15 years.
There is a zero probability that this object will hit the Earth this week. Its orbit is well enough known that not only will it not hit the Earth but it will also not be impacting any Earth-orbiting satellites. There is a 1-in-50,000 chance DA14 could hit the Earth in the years between 2080 and 2109, though it is likely that even these small impact probabilities will drop to zero after this week’s flyby.
As close as this asteroid gets to Earth, it small size means it never gets very bright. It will brighten to about 7-8th magnitude at its closest which will make it an easy binocular or small telescope object. The hard part will be finding it. It will be moving as fast as nearly a degree per minute at its fastest. Not too mention being so close also means parallax will be an issue.
By the time the sun sets in the United States, it will have faded to 11th-12th magnitude. Only observers with relatively large telescopes will be able to spot DA14 by then as it recedes into the distance near the north star, Polaris.