By John Larson
A husband and wife astronomy team at the Magdalena Ridge Observatory on Nov. 16 documented the second-fastest spinning asteroid on record, missing the earth by about 20,000 miles.
Asteroid 2010 WA was tracked by Bill Ryan, the leading astronomer at the New Mexico Tech facility, using a 2.4-meter telescope. The rock measures about 10 feet in diameter and completes a rotation about every 31 seconds. By comparison, the fastest spinning asteroid, known as 2010 JL88, also discovered by Ryan, takes 24.5 seconds to complete a rotation.
His wife, Eileen Ryan, director of the 2.4-meter telescope, says that the only danger that the asteroid presented was that it had entered the path of satellites in geosynchronistic orbits, which stationary orbits generally above the equator. Those satellites are generally used for global positioning (GPS), weather forecasting, television broadcasting, and defense or intelligence purposes.
There are about 300 satellites at that altitude, according to Eileen Ryan. “If an asteroid were to hit one of those,” she said, “it would understandably cause disruption of services on which we commonly depend. And those are quite expensive pieces of equipment.”
Tracking asteroids is one of the main operations of the telescope, which first went into operation in November 2006.
“We’ve tracked four asteroids in the last month that came that close to the earth,” said Eileen Ryan. She said studying the rotation rate can help scientists understand the geology of the rock passing by.
“The rate of spin, which we are learning about for the first time,” she said, “can tell us about the material of bodies in the asteroid belt.”
In years past, she added, there wasn’t a reliable system for studying an asteroid’s rate of rotation, but her husband has since devised a method which involves spotting them early on and picking out the best candidates.
The Magdalena Ridge Observatory has been involved in a variety of asteroid studies and has built a reputation on being a leader in the field. On a recent Discovery Channel program, “Phil Plait’s ‘Bad Universe: Asteroid Apocalypse’”, Eileen Ryan discussed the observatory’s asteroid studies, explaining that 10 or 12 asteroids might be discovered on any given night.
“We have to assess are they a danger, how strong are they, how big are they,” she said during the program. “All of the work we do can be used for predictions on when or where an object will hit.”
And what about other flying objects?
“We work with NASA, the National Science Foundation, and Los Alamos National Laboratory,” said Eileen Ryan. “We’re also working with the Air Force to track satellites. And if we’re called on to track Santa Claus on Christmas Eve, we’ll do what we can.”