Asteroid images from ground confirmed by spacecraft flyby

  • Published
  • By Jeanne D. Dailey
  • Air Force Research Laboratory
Kirtland Air Force Base --  In July, the European Space Agency Rosetta spacecraft beamed back to Earth impressive images of the 100-kilometer-sized asteroid, Lutetia.
Astronomers using three of the world's largest ground-based telescopes were making their own assessments of the asteroid's shape and size.
Their Rosetta pre-flyby images were compared at an October meeting of the Division for Planetary Science of the American Astronomical Society in Pasadena, Calif, revealing that the groundbased images are astoundingly accurate.
Dr. Jack Drummond, an Air Force Research Laboratory astronomer at the Starfire Optical Range here and an observation team member, reported, "We carefully evaluated the size and shape of Lutetia, and pinned down the orientation of its spin pole using telescopes
on Earth, prior to the flyby. After many years developing these techniques at Starfire, it is gratifying to see how they work when put to this kind of test."
Adaptive optics was first developed at the Starfire Optical Range in the early 1990s and is considered the cradle of adaptive optics.
Jack Drummond is an expert in turning AO images into models of asteroids, detailing their shapes and sizes. He is the lead author on the first of two papers predicting the appearance of Lutetia, both published in the journal Astronomy and Astrophysics.
In addition to Dr. Drummond, the international team consisted of team lead Dr. William J. Merline and Dr. Clark Chapman of the Southwest Research Institute in Boulder, Colo, Dr.
Benoit Carry of the European Space Research Institute in Paris, France, and Dr. Al Conrad of the Keck Observatory on Mauna Kea, Hawaii.
The AFRL Directed Energy Directorate's Starfire Optical Range is a vital resource in achieving the Air Force's mission to operate freely in space.
The SOR operates one of the world's premier adaptive optics telescopes capable of tracking low-earth orbiting satellites. At 3.5-meters, the telescope is the second largest in the Department of Defense.
The SOR's primary mission is to develop optical sensing, imaging, and atmospheric propagation technologies to support Air Force aerospace missions.
Note: images are available at http://www.boulder.swri.edu/merline/press.