An asteroid half the size of a football field will make a close approach to Earth, but poses no threat of smacking into the planet, NASA officials said today (Feb. 7).

The asteroid 2012 DA14will approach within 17,200 miles (27,680 kilometers) of Earth when it zips by during its close encounter next Friday, Feb. 15. That is the closest shave ever for an asteroid the size of 2012 DA14, which is about 150 feet (45 meters) wide, that astronomers have known about in advance, NASA scientists said.

The asteroid will not only pass between Earth and the moon's orbit, but also fly lower than the ring of geosynchronous communications, weather and navigation satellites that fly high above the planet. Asteroid 2012 DA14 will be 5,000 miles (8,046 km) closer to Earth than those satellites during the flyby.

"This asteroid seems to be passing in the sweet spot between the GPS satellites and weather and communications satellites," Don Yeomans, the head of NASA's asteroid-tracking program, told reporters in a teleconference today (Feb. 7). "It's extremely unlikely that any of these will be impacted." [See Asteroid 2012 DA14's Close Flyby in Action (Video)]

Geosynchronous satellites typically orbit about 22,000 miles (35,800 km) above the Earth's equator.

Record-setting space rock flyby

Asteroid 2012 DA14's close encounter is also a record-breaking celestial event, Yeomans said. An object this large only passes this close to the Earth about once every 40 years, and likely only hits the planet once every 1,200 years, he added.

Amateur astronomers have already captured some photos of asteroid 2012 DA14, and NASA plans to make detailed radar observations of the space rock to learn about its composition, spin and surface features, the scientists said.

The asteroid is similar in size to the object that exploded over Siberia, Russia, in 1908 in the Tunguska event. That explosion leveled hundreds of square miles of land, scientists said. While asteroid 2012 DA14 could potential create such destruction if it struck the Earth, there is absolutely no chance of an impact for the foreseeable future, NASA officials said.

"This asteroid's orbit is so well known that we can say with confidence that even considering its orbital uncertainties, it can pass no closer than 17,100 miles from the Earth's surface," Yeomans said. "No Earth impact is possible."

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Asteroid Flyby Next Week One for the Record Books, NASA says