A large asteroid, known as 2011 AG5 and big enough to release 100 megatons of energy, will miss Earth in 2040 after NASA narrowed down it’s cone of uncertainty, revealing that it’s no longer a threat to mankind.
Astronomers took up the task to manage the astroid from the University of Hawaii at Manoa for several days in October.
“An analysis of the new data conducted by NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California, shows that the risk of collision in 2040 has been eliminated,” NASA said.
The new observations, made with the Gemini 8-meter telescope in Mauna Kea, Hawaii, reduce the orbit uncertainties by more than a factor of 60. That means the Earth’s position in February 2040 is not in range of the asteroid’s possible future paths.
The asteroid, which is 460 feet in diameter, will get no closer to Earth than 553,000 miles, or more than twice the distance to the moon, NASA said.
A collision with Earth would have released about 100 megatons of energy, several thousand times more powerful than the atomic bombs that ended World War II, according to the Gemini Observatory.
Observing the asteroid wasn’t easy, said David Tholen, an astronomer at the University of Hawaii Institute for Astronomy.
The asteroid’s position was very close to the sun, so astronomers had to observe it when the sky was dark. Tholen told CNN there was about a half-hour between when the asteroid got high enough in the sky for the telescope to point at it and before the sky became too light to observe it.
Because the astronomers were looking at the asteroid low in the sky, they were viewing it through a lot of atmosphere, which scattered some of the light and made the object fainter, he said.
“The second effect is the turbulence of the atmosphere makes things fainter,” Tholen said. “We had to keep trying over and over until we got one of those nights when the atmosphere was calm.”
The last near miss astroid was known as “2005 YU55,” which passed by Earth on November 8, 2011. The meteorite is the same size as an aircraft-carrier. It was the largest near-miss for the planet in three decades.