WASHINGTON -- The Feb. 19 explosion of a Russian Breeze-M rocket stage launched a year ago created an amount of orbital debris on "the same order of magnitude" as the Jan. 11 Chinese anti-satellite (A-Sat) test, a NASA debris scientists said Feb. 23.

 

"This is an unprecedented set of events in terms of such large breakups in such a short time," Mark Matney, an orbital debris scientist at NASA's Johnson Space Flight Center, said Feb. 23.

 

The Proton debris is in a highly elliptical orbit with an apogee of 15,000 kilometers and a perigee of 500 kilometers. That means the Proton debris will remain in orbit for several decades because the time spent at perigee is very short, Matney said

 

The Breeze-M upper stage, part of a Proton rocket launched Feb. 28, 2006, by International Launch Services, was supposed to deliver the Arabsat 4A satellite into geosynchronous orbit. It failed and, for unknown reasons, the hypergolic fuel-laden rocket exploded almost a year later. Debris larger than 10 centimeters is being tracked although Matney said the official catalog of space debris had not yet been updated. The Air Force personnel responsible for tracking debris catalog "are pretty busy" building the catalog of the debris field from the Chinese FY-11 weather satellite destroyed during the anti-satellite test, the NASA scientist said.

 

There are also reports of another February debris event. Observers in Finland photographed the apparent explosion of an auxiliary motor on a Russian SL-12 rocket Feb. 14, according to T.S. Kelso, technical program manager at the Center for Space Standards and Innovation in Colorado Springs, Colo., a research arm of Analytical Graphics Inc. "These events are most unusual. If they are indeed both on-orbit explosions, that would make two events in less than a week. According to the NASA Orbital Debris Program Office, there were only eight events all of last year, and that was the most since 1993," Kelso said in a Feb. 23 e-mail.