If your satellite TV goes out on Friday, can you blame it on an asteroid?
Highly unlikely, say scientists monitoring the approach of asteroid 2012 DA14, which will zoom closer to Earth on Friday than any other known object of its size.
The celestial visitor, which is almost as wide as the length of an Olympic-sized swimming pool, is due to pass as close as 17,100 miles at 2:24 p.m. EST (7:24 p.m. GMT) on Friday. That's closer than the television and communications satellites which circle the planet some 500 miles higher.
"This asteroid seems to be passing in the sweet spot between the GPS satellites (which fly at about 12,600 miles above Earth) and the communication and weather satellites, so it's really extremely unlikely that any of these satellites would be threatened," said Donald Yeomans, who oversees NASA's Near-Earth Object Program at the Jet Propulsion Laboratory in Pasadena, Calif.
NASA has been providing details of the asteroid's flight path to satellite operators so they can determine how close it will pass to their particular spacecraft.
"No one has raised a red flag," Yeomans told reporters during a conference call last week. "I certainly don't anticipate any problems."
"I don't know of any odds for a satellite hit, but it must be a very low probability," Yeomans added Tuesday in an email to Discovery News.
Members of the Satellite Industry Association were not taking any particular precautions that the trade group is aware of, added spokeswoman Marie-Pierre Pluvinage.
The non-profit Space Data Association, which shares satellite-tracking information among its member organizations and companies, said it had looked at the asteroid's projected flight path and determined none of the spacecraft monitored in its network would be impacted, chairman Ron Busch told Discovery News.
There’s no chance DA14 will hit Earth, though an object of its size can be expected to strike the planet about once every 1,200 years or so.
"Basketball-sized objects come in daily. Volkswagen-sized objects come in every couple of weeks. As you get to larger and larger sizes the number of objects out there is less and less, so the frequency of hits goes down," Yeomans said.
The orbital trajectory of 2012 DA14 on Feb. 15, 2012.NASA/JPL-Caltech
Overall, about 100 tons of space rocks, most the size of sand grains and pebbles, blast through Earth's atmosphere every day.
As asteroid of DA14's size, which is about 150 feet in diameter, wouldn't cause global catastrophe if it did hit like the six-mile wide object that slammed into what is now Mexico’s Yucatan peninsula, triggering climate changes so severe and long-lasting that dinosaurs, among other plant and animal life, vanished some 66 million years ago.
Moving at about 8 miles per second, an object of DA14's size on a collision course with Earth would strike with the force of about 2.4 million tons of dynamite, the equivalent of hundreds of Hiroshima-type bombs.
"They still do a lot of regional destruction," said Lindley Johnson, who oversees the Near-Earth Object Observations Program at NASA headquarters in Washington DC.
In 1908, for example, an asteroid or comet blasted apart as it approached Siberia, destroying 80 million trees over 830 square miles in the process.
DA14 was just discovered last year, though astronomers suspect it has been regularly visiting Earth for some time. The asteroid is smaller than the objects NASA has been tasked to track, though astronomers are making progress on cataloging all the celestial objects that orbit near Earth.
DA14 will be even less likely to harm Earth in the future. Its close encounter on Friday should tweak its orbit so that upcoming encounters will be fewer and farther away.
"The close approach (on Friday) will perturb its orbit so that actually instead of having an orbital period of one year it’ll lose a couple of months," Yeomans told Discovery News.
"We ran it out for 100 years and there is no closer approach in the foreseeable future. The Earth is going to put this one in an orbit that is considerably safer," he said.