By Charlene Porter
An asteroid about the length of an Olympic pool is going to zip past Earth February 15.
Amateur astronomers in Eastern Europe, Asia and Australia will be able to see the flyby with a moderately powered telescope.
The Near-Earth Object Program at NASA announced the flyby February 7, after tracking the object since the first sighting about a year ago. Scientists explained the phenomenon in a news briefing, expressing complete confidence that the space rock they named 2012 DA14 will not strike our planet.
The asteroid is going to slip between the Earth and the geosynchronous communications satellites ringing the planet, according to Donald Yeomans, manager of the Near Earth Object Program Office at NASA’s Jet Propulsion Laboratory. He says observations remain somewhat uncertain about the size of the object, but “it is thought to be 45 meters in diameter. It will pass within 17,200 miles [about 27,700 kilometers] of the Earth’s surface.”
The asteroid will reach its closest point to Earth at about 19:24 UTC (2:24 EST), and will be traveling more than 28,000 kilometers per hour or almost 8 kilometers per second.
That’s “very fast for a celestial object,” Yeomans said.
Detection of the 2012 DA14 flyby is a record achievement for this specialized field of astronomy. The La Sagra Sky Survey operated by the Astronomical Observatory of Mallorca in Spain first detected this asteroid in February 2012 when it was about 4.3 million kilometers away.
La Sagra reported the information to the Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics in Massachusetts, said center director Timothy Spahr. Subsequently a network of astronomers around the world provided more observations, giving the Minor Planet Center sufficient information to calculate the path of the object.
“With a good orbit,” Spahr said, “we can predict the motion of an asteroid in the future and assess its potential to be dangerous to the Earth.”
These scientists have no worries that 2012 DA14 will come crashing into Earth, but they acknowledge it would be a cataclysmic event if it were to do so. Asked about the potential damage of an object this size, Yeomans compared it to a 1908 incident, now known as the Tunguska impact.
That event occurred “when a similarly sized object collided with the Earth over in Russia’s Siberia,” Yeomans said, “and caused significant ground damage, leveling millions of trees for over 820 square miles [2,070 square kilometers].
By current estimates, Yeomans said, an object the size of 2012 DA14 can be expected to pass this close to Earth every 40 years or so. The collision of Earth with a large space rock is calculated to occur about every 1,200 years.
NASA launched the Near-Earth Object Program 15 years ago, with the mission of identifying all the asteroids of 1 kilometer or larger that could have potential to impact the Earth.
“We’ve done a pretty good job of that,” said Lindley Johnson, program executive. “Our estimates show that we’ve found about 95 percent of those large asteroids that come close to the Earth.”
The search now focuses on smaller objects, like 2012 DA14, which wouldn’t cause a global catastrophe, but could still cause serious regional destruction.