Part of the U.S. Strategic Command's job is to keep spacecraft from crashing into the tens of thousands of bits of space junk floating around the Earth. Now it's getting some help from other countries.
StratCom's commander, Gen. Robert Kehler, signed “space situational awareness” agreements this spring with U.S. allies Japan and Australia. The pacts will make it easier and faster for StratCom to swap information to help satellites and spacecraft avoid the orbiting detritus from 56 years of space travel. StratCom leaders hope more nations will follow suit.
“It's important for us to preserve the space domain,” said Col. Lina Cashin, chief of StratCom's policy and doctrine division, which is negotiating the agreements. “We need to rely on our partners and allies.”
Until 2004, space-faring nations mostly launched rockets with fingers crossed that the vastness of space would protect them from being hit by others' orbiting debris.
“We had the big-sky theory, that there was a lot of room in space,” Cashin said.
Amid rising fears about space junk, the Air Force launched a pilot project and created a website — www.space-track.org — to provide data on those objects circling the planet that are roughly of baseball size or larger. At the time there were about 10,400.
The next few years showed how severe the problem could become. In 2007 the Chinese conducted a test, firing a missile to shoot down an old weather satellite. That created nearly 3,400 cataloged chunks of junk, according to data from NASA's Orbital Debris Program Office. Some of that junk is expected to orbit for up to 100 years.
Then, two years later, came the disaster that space scientists had feared. An active Iridium satellite from Motorola collided with an inactive Russian Cosmos weather satellite. The crash created another 2,100 pieces of space debris.
“That was a wake-up call,” said Yool Kim, a national security policy researcher who studies space issues for the RAND Corp. “These two events made everyone realize that space is becoming increasingly congested.”
The Air Force's tracking program hadn't foreseen the collision. At the time, Cashin said, the U.S. military kept watch over spacecraft carrying people, or those belonging to the Defense Department and other U.S. government agencies. It didn't cover dormant payloads such as Cosmos or commercial spacecraft like Iridium.
When StratCom took over the Air Force's experimental website in late 2009 it expanded the program to cover all active spacecraft and added more spaceflight-safety services.
Through a network of sensors around the world, StratCom's Joint Space Operations Center — which goes by the acronym JSpOC — now monitors more than 17,000 space objects. Between 20 and 30 times a day, Cashin said, the space operations center issues alerts if it forecasts two of the objects are about to collide. Actual collisions remain rare.
Still, there are close calls. In 2011, astronauts in the International Space Station had only 14 hours' warning to take shelter in their Soyuz “lifeboat” capsules after an unidentified piece of space junk passed within about 800 feet of the station. Last year they took shelter again when a chunk of debris from the Iridium-Cosmos crash passed uncomfortably close.
What scientists fear is that low-Earth orbit will become too crowded for safe launches because of the increasing space flotsam created by collisions. Because of the speed at which objects move in space — up to 17,500 miles per hour — even tiny pieces of junk can badly damage spacecraft.
“Even if it's a small object, you're talking about a lot of momentum,” Kim said.
More groups than ever are launching into space. At least 14 nations and more than 40 international groups and private entities have objects in orbit.
“There are new entrants every day,” Cashin said.
Playing traffic cop in space has become a job too big for the United States on its own.
So Congress in 2009 authorized the sharing of “space situational awareness” data outside the government. StratCom received authority to reach data-sharing agreements with private companies and international groups that launch into space. Later it was authorized to negotiate directly with foreign governments.
Besides the agreements with Japan and Australia, Cashin said, StratCom has completed 37 agreements with international groups and companies. At no charge, StratCom agrees not only to share up-to-the-minute data on space junk, but offers extra assistance during launch and re-entry, during an emergency, or when a satellite is nearing the end of its life.
“We're trying to make it more useful for our partners,” Cashin said.
Those partners, of course, must also make their data available to StratCom.
“It's all about sharing information,” Kim said. “The end goal is to try and obtain a stable and safe environment.”
Still, the prospect of data swapping raises alarms in some quarters. They warn that the United States should make certain it doesn't give up its rights to operate freely in space — or its secrets — in the name of transparency.
“The U.S. always overcomplies with agreements while others undercomply,” said Michaela Dodge, a space and defense policy analyst for the Heritage Foundation, a conservative think tank. “The magical belief that the U.S. will set an example and others will follow — that's just mythology.”
Dodge agrees that space debris poses a growing danger to space commerce.
“Information sharing may be OK as long as you protect your intelligence,” she said. “I'm not saying it's not good. It's just that we have to be very, very cautious.”
Cashin said StratCom isn't spilling any secrets. All of the information it shares is unclassified.
“It behooves us to be safe and responsible,” she said. “This data has been already out in the public domain.”
StratCom won't say what other countries are in the running. Kim said it's logical to guess that the nations with which the U.S. already has space agreements — Canada, Great Britain, France — may sign on next.
It's agreed, though, that simply sharing what's known about space junk won't stop the threat. The Air Force Space Command has projected the amount of debris will triple by 2030.
The Pentagon's Defense Advanced Research Projects Agency is already beginning to study super-high-tech ways of cleaning up space, such as zapping orbiting debris with ground-based lasers or deploying space ships with giant nets to scoop it up.
But with those solutions still at the outer edge of sci-fi fantasy, the answer for now appears to be for those who launch into space to talk to each other so that it is easier for them to see and avoid the debris.
“They're trying to attack the problem as a (space-faring) community,” Kim said. “Strategically, it's definitely a right step.”
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