MSNBC / SPACE.com
Mon, 11 Oct 2010 16:04 UTC
A small asteroid will zip close by Earth Tuesday (Oct. 12), but poses no chance of hitting the planet or even entering the atmosphere, NASA has announced.
The asteroid 2010 RD54 will fly within about 28,000 miles (45,000 km) of Earth when it makes its closest pass at about 6:51 a.m. EDT (1051 GMT) tomorrow morning, NASA spokesman D.C. Agle told SPACE.com.
The small asteroid is about 20 feet (6 meters) wide and expected to drift silently by Earth instead of creating a dazzling fireball in the atmosphere. The asteroid is too small to survive all the way to the ground, even if it was aimed at Earth, scientists said.
"Small space rocks this size would burn up in our atmosphere & pose no ground danger," NASA's Asteroid Watch group posted on Twitter.
Asteroid Watch is a public outreach effort by NASA's near-Earth objects office at the Jet Propulsion Laboratory in Pasadena, Calif. The group of scientists regularly posts asteroid flyby and sighting alerts on Twitter under the name AsteroidWatch.
Asteroid 2010 RD54 may be visible to skywatchers with moderate telescopes, but will be hard to spot, NASA officials said. Seasoned asteroid hunters may be the best equipped to catch a glimpse, they added.
"A moderate telescope required; it is very small," the Asteroid Watch group wrote on Twitter.
The asteroid will fly well inside the moon's orbit of Earth, and even pass just above some of the highest satellites, which fly in geostationary positions about 22,370 miles (36,000 km) above Earth. For comparison, the International Space Station flies at an altitude of about 220 miles (354 km).
When space rocks like Asteroid 2010 RD54 encounter Earth's atmosphere, they can burn up in spectacular fire balls, but never reach the Earth.
Bigger asteroids about 460 feet (140 meters) wide can cause widespread damage around their impact sites, but for global devastation much larger space rocks would have to strike the Earth.
NASA routinely tracks asteroids and comets that fly near Earth, using a network of ground and space telescopes as part of its Near-Earth Object Observations program. According to the most recent report, the program has tracked about 85 percent of the largest asteroids that fly near Earth and about 15 percent of asteroids in the 460-foot class.
NASA is also planning to tackle a new space plan ordered by President Obama to send astronauts to an asteroid by 2025. The mission, agency officials have said, could help scientists better understand the composition of asteroids and develop improved methods of deflecting them before they endanger the Earth.