Space Debris: US Air Force Holds Satellite Collision Avoidance Data

The U.S. Air Force remains undecided about how much data it will make available on the whereabouts of satellites and orbital debris beyond what it publicises now, as it weighs orbital traffic safety concerns against the national security penchant for secrecy.

Two years ago an active Iridium Communications satellite and a retired Russian Cosmos spacecraft slammed into each other, spewing thousands of pieces of debris across popular orbital routes. This was the worst-ever collision of man-made objects in orbit.

Even now, the US Air Force is still grappling with how much of the data, which it harvests from ground-based radars, should be made public, Richard W. McKinney said.

Commercial satellite operators and others interested in the growing problem of space debris have long requested the U.S. military to loosen its grip on what it harvests from its sensors, which feed into a catalogue of orbital objects.

A select portion of that catalogue, called Two-Line Elements (TLEs), is made public to give basic information on a satellite’s whereabouts.

Following the Iridium-Cosmos collision, the Air Force agreed to review whether it should be making public a larger share of the data it collects. McKinney said that process continues.

“We’re looking at that, and we’re looking at M2M relationships,” McKinney said at the MilSpace 2011 conference organised by SMi Group of London, referring to automated, machine-to-machine communications that would manage data dissemination. “A policy on how we would share data, and whether we go beyond TLEs, is part of the review.

“There are some real security issues involved, but having said that, I can say we don’t want to see another collision in space, because that would create yet more debris and that would make further collisions even more frequent.”

The U.S. Space Surveillance Network is about to undertake a major upgrade of the Space Fence, a group of Very High Frequency radars deployed across the United States in a line at about 33 degrees north latitude.

The upgrade, for which two design contracts worth $107 million, have been awarded to competing teams led by Raytheon Integrated Defense Systems and Lockheed Martin Mission Systems and Sensors.

These will feature higher-frequency, S-band radars able to detect smaller pieces of orbital junk in low and medium Earth orbit. The Air Force has estimated that the new Space Fence, which could be operational by late 2015, will cost $3.5 billion.