A German student’s refinement of the space rock Apophis’ chances of smacking Earth in the next few decades has caused quite an international stir, even if he happens to be wrong.

Apophis, or Asteroid 99942, is a space rock between 690 and 1080 feet (210 and 330 meters) wide that scientists expect to make two close swings by Earth, first in 2029 and then again in 2036.

After careful analysis, NASA scientists have given the space rock a slim 1-in-45,000 chance of walloping Earth on its second pass, adding that the Apophis bears watching because perturbations in its path could require more calculations.

But when German student Nico Marquardt, 13, made his own calculations using telescopic observations from the Institute of Astrophysics in Potsdam, he came up with a 1-in-450 chance the asteroid would collide with Earth if it ran into a manmade satellite in geosynchronous orbit some 22,300 miles (36,000 km) above the planet, according to the German newspaper Potsdamer Neuerster Nachrichten and the AFP wire service. He submitted the findings for his regional science competition with the title: ‘Apophis – The Killer Asteroid,’ and found confirmation from folks at NASA and the European Space Agency, the publications reported.

But another report, from a different news outlet – and later officially confirmed by NASA itself – laid down the law: A 1-in-45,000 of impact. And those are mighty good odds. One eagle-eyed reader alerted SPACE.com this morning that a simple percentage error may be at the heart of Marquardt’s findings.

“Contrary to recent press reports, NASA offices involved in near-Earth object research were not contacted and have had no correspondence with a young German student, who claims the Apophis impact probability is far higher than the current estimate,” NASA officials said.

Apophis seems to have an on again-off again relationship with the people of Earth. Despite NASA’s increasingly more refined observations suggesting it won’t whack us a good one in 2036, reports seem to trickle out through in the media every year about how it will.

And how awful! An 200 billion-ton impact in the Atlantic Ocean spawning tsunamis large enough to wipe out the U.S. East Coast and the western coast of Europe. Clouds of dust that blot out the sun for who knows how long, according to press reports.

But NASA says that, right now, that won’t happen.

Current estimates based on asteroid tracking by NASA’s Spaceguard project predict Apophis zip by Earth at a distance of about 18,300 miles (29,470 km) on its first pass in 2029, then swing further out at about 30 million miles (47.9 million km) in 2039. Its course will not bring it near the main belt of geosynchronous satellites, NASA said.

Perturbations in its orbit do bear watching to ensure that the odds of an Earth impact don’t increase, but they are holding steady at 1-in-45,000, the agency added.

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