Here we go again. Heard of the latest asteroid to strike terror across the Web? It’s 2012 DA14, a flying rock almost 150 feet across discovered on February 23 by astronomers at Observatorio Astronomico de La Sagra in Spain. The observatory uses robotic telescopes to find and track near-Earth asteroids. At the time of discovery, DA14 was passing Earth at a fairly typical distance of 1.5 million miles.
After calculating a preliminary orbit for 2012 DA14, astronomers learned that on February 15, 2013, it will zoom by only 17,000 miles from the surface of our planet. While this is very close by solar system standards, it’s a long ways for you and I. If you consider that the diameter of Earth is about 8,000 miles, this small object will miss us by more than twice that. While it will very briefly pass through the geosynchronous satellite belt, the odds of it hitting one are extremely small. The average separation between satellites there is 59 miles. A geosynchronous satellite orbits 22, 236 miles above Earth, an altitude where the satellite’s orbital period matches Earth’s rotation. That means they’re essentially stationary in the sky, making them ideal for relaying communications around the globe. But I digress.
Some websites are saying a strike is imminent or at the very least possible. The fact is, it won’t happen in the foreseeable future. Yes, it’s possible that sometime in the distant future, there might be a closer pass or even a dead-on hit, but that’s not in the cards for now. On the Torino Impact Hazard Scale DA14 rates a “0”, defined as:
The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage.
And on the related Palermo Impact Scale, it comes in at a -4 , meaning there will be no consequences during this flyby. You might recall the hype surrounding the even closer flyby of asteroid 2011 MD last June. That asteroid, which measured between 3o and 150 feet across, came even closer than DA14 will at a distance of only 7,500 miles. We all survived.
Ongoing surveys like the one at La Sagra are underway to find every possible rock big enough to put the hurt on Earth. Most of the asteroids measuring one kilometer or more have been seen and their orbits determined, but there are still plenty of extremely faint and small rocks out there like DA14. Expect many more to be found in the coming years.
NASA’s Jet Propulsion Lab has released several excellent 3D images recently that give you that “being there” feeling. To see depth in the photos, you’ll need a pair of those red-blue specs called 3-D anaglyph glasses. Click HERE to order a free pair.
In addition to creating detailed photographic maps from its 130-mile-high orbit, Dawn’s been looking for water ice in the asteroid’s polar regions. While none has been discovered yet, the temperature there is colder than -200 F, the cutoff for water to exist in the top 10 feet of Vesta’s rocky soil. The “warmer” equatorial regions hovers around -190 F.