More than a half million pieces of space debris are orbiting the earth, at speeds up to 17,500 miles per hour, causing safety concerns for astronauts aboard the International Space Station and threatening to damage or destroy spacecraft and critical military, intelligence, communications, weather and navigation satellites.
Richard Rast, a senior engineer at the Air Force Research Laboratory, created an innovative way to track this space debris to help reduce the risk of potential collisions—a system that could become a cost-effective supplement to the current processes used by the Air Force and NASA that rely on expensive telescopes, radar systems and considerable manpower for analysis.
Rast’s invention uses a series of small telescopes developed by Los Alamos National Laboratory that capture the faint light signals entering the lens. Rast converts the camera photos into a movie, where he uses the human eye’s sensitivity to detect variations between frames to separate man-made objects from the star background and identify objects the size of just a few centimeters.
“Richard Rast demonstrated that his small telescope approach can find and track space objects at a much lower cost than traditional methods and provide a quality of data previously assumed impossible for a small telescope system to achieve,” said Maj. James Thomas, the chief of the Air Force Research Laboratory’s Satellite Assessment Center at Kirtland Air Force Base in Albuquerque, N.M.
Rast’s small telescopes are portable, providing an added advantage to the large telescopes now in use that cannot be easily repositioned to capture critical images and therefore can potentially miss valuable information.
“He is breaking new ground,” said Thomas. “We are on the cutting edge of being able to discover and track objects in the farthest orbit, the geostationary belt. Before that, they looked like blips. Richard’s techniques help identify these objects.”
Air Force Capt. Stephen Bump, the assessment center’s acting deputy branch chief, said Rast’s ability to use small portable telescopes to see things in space, predict collisions and warn satellites to avoid them is “just now taking hold and it is going to continue to grow.”
“This is the future of space situational awareness,” said Bump.
A five-telescope version of Rast’s system is currently being tested by the Air Force in Hawaii. The Air Force is also evaluating locations for a 16-telescope system that will serve as a pilot project and, if successful, will become part of the Air Force’s permanent space surveillance system.
Being aware of objects in space is critically important because of the nation’s reliance on satellites. If satellites are damaged by space debris, it costs millions of dollars to replace them and can take down vital communications, surveillance, navigation, timing, weather, imagery and military systems.
As satellites reach end-of-life and are replaced with new versions, the old equipment and the boosters often are not properly de-orbited or moved to safe disposal orbits, creating the growing hazard. The space debris currently orbiting the earth includes more than a half million objects, of which more than 20,000 pieces are larger than a softball and are traveling at extraordinarily high speeds.
The risk was dramatically depicted in the recent Academy Award-winning film Gravity, in which high-speed debris strikes the space shuttle, sending a medical engineer aboard the orbiting laboratory hurtling into space and touching off a series of catastrophes.
The real-life dangers of floating debris became evident in March 2014 when astronauts aboard the space station were forced to raise its altitude by half a mile in order to dodge a piece of an old weather satellite predicted to come within 1,900 feet of the station.
Thomas noted that recent budget cutbacks have reduced the ability of some government facilities to maintain their observational capabilities, putting all space platforms at greater risk of accidental damage. The Air Force had to disable its radar fence, the Space Surveillance System, across the entire southern United States, for example, and manpower for data analysis at other tracking facilities is being severely stretched.
Rast has used his experimental system on a number of occasions, including to locate a satellite that had drifted far from its original orbit and had been lost for a decade.
The Air Force engineer also was able to use his small telescope to capture video of a laser beam fired from the CALIPSO, a joint NASA and French space agency satellite. The telescope’s portability and Rast’s ability to be in the right place at the right time helped enable the discovery. The result made NASA aware that CALIPSO’s laser is a potential eye hazard for people observing from earth.
An avid amateur astronomer, Rast first experimented with his invention for a project some years ago and was startled that he could see the same satellites as much larger telescopes. After telling his boss about the discovery, his space debris project got underway.
Rast said he sees his role as helping government organizations become aware of and embrace new technology and new ideas. Working at the Air Force Research Laboratory, he said, also gives him the “freedom to be creative and think outside the box” to help his country.