Comet C/2010 X1 was named after Leonid Elenin (Леонид Еленин), a Russian amateur astronomer who discovered it on 10 December 2010. He was remotely using the International Scientific Optical Network’s robotic observatory near Mayhill, New Mexico, USA. It is not a very spectacular object: even at its brightest, it will be 25 times too faint for the naked eye to see. It is probably only about 3–4 km in diameter. It’s most likely a lot smaller than the famous Halley’s comet, which has a mass of 2.2×1014 kg. This sounds a lot, but the earth’s mass (M⊕) is 5.9722 × 1024 kg—27 billion times more.
Furthermore, its closest approach to Earth is 34.4 million km (21.4 million miles) on 16 October 2011—this is about the same as the closest approach of Venus. Venus has 81.5% of the mass of the Earth, and poses not the slightest threat. So a fortiori, how much less will a little pipsqueak snowball at about the same distance, with only 0.000,000,003% of the earth’s mass?