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Watching an asteroid’s spin. Image courtesy Alexandra Bolling, NRAO/AUI/NSF
Scientists will use New Mexico’s Very Large Array radio telescope to track an asteroid passing close to Earth later this week:
A 150-foot-wide asteroid called 2012 DA14, discovered just a year ago, will pass only 17,200 miles above the Earth on Feb. 15. That’s closer than the geosynchronous communication and weather satellites. While the object definitely will not strike the Earth, this is a record close approach for an object of this size. Astronomers around the world are preparing to take advantage of the event to study the asteroid.
Astronomers from all over the world will be watching. The VLA group’s goal is to study the object’s spin:
Because of the asteroid’s uneven surface and the different reflectivity of portions of the surface, the reflected radar signal will have a characteristic signature, or “speckles,” as observed from Earth. By measuring which antenna in a widely-separated pair receives the speckle pattern first, the astronomers can learn which way the asteroid is spinning. This way of using the telescopes is significantly different than their normal astronomical observing, and the research team has developed special techniques for processing the data.
Sadly for us, according to VLA spokesman Dave Finley, this isn’t the sort of event that will be easy to go out in your backyard and watch.
-- Email the reporter at jfleck@abqjournal.com. Call the reporter at 505-823-3916
