Asteroid Flies Near Earth

Cornell astronomers were able to shoot delay-doppler radar images of an asteroid called 2007 TU24 as it flew past earth yesterday. Using the Arecibo Observatory and the Green Bank Telescope as a bistatic-radar system, astronomers transmitted radio signals from the Observatory in Puerto Rico off the asteroid and then sent them to the Robert Byrd Greenbank Telescope in West Virginia.
Although astronomers were able to capture images, the asteroid was smaller than they had predicted, at about .2 km in diameter.
“We expected it to be bigger based on how bright it was,” said Michael Nolan, of Cornell’s Arecibo Observatory.
Cornell’s Arecibo Observatory is one of only two facilities in the world — the other is a NASA facility in California — that has the technology to capture such images. The next time an asteroid of that magnitude is predicted to pass is in 2027.