The Russian news agency Interfax reported that the explosion generated about 500 pieces of debris. The previous Briz-M explosions each produced about 100 pieces of debris, according to NASA's orbital debris program office.
Another Briz-M upper stage from a botched August 2011 launch is still in orbit and has not yet ruptured.
In all, there are more than 21,000 pieces of orbital debris larger than 10 cm ( about 4 inches). Scientists estimate there are about 500,000 pieces of debris between 1 and 10 centimeters (about 0.4 inches to 4 inches) and more than 100 million pieces of space junk smaller than 1 centimeter.
Images: Top: File photo of a Briz-M upper-stage rocket motor which broke apart Oct. 16. Credit: Khrunichev. Credit: NASA.