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Many questions, few answers when it comes to space traffic management, experts say

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WASHINGTON – With an ever growing number of countries and corporations launching satellites into orbit, there’s never been a greater need for thorough tracking of objects in space, but many questions need to be answered first, according to a panel of experts at a recent conference.

“The time is now to address this issue,” said George Nield, Federal Aviation Administration associate administrator for commercial space transportation, speaking at a panel on space situational awareness (SSA) at the American Institute of Aeronautics and Astronautics Science and Technology Forum held in Grapevine, Texas, Jan. 11. “We need to avoid the temptation because it is a complex and challenging problem to try to get everything perfect before we start taking action.”

One of the first issues for any new space traffic management system is data collection. “There’s great work to be done on the collection side,” said Mike Gazarik, vice president of engineering at Ball Aerospace. “How do you want to collect the data, from space or on the ground?… Are we doing it for the nation or the world? Well, that’s difficult to separate in space.”

Donald Greiman, vice president of commercial space situation awareness at Schafer Corporation, said that whoever is in charge of SSA would need their own way to collect data on objects in orbit, similar to air traffic control radar used by the FAA.

Developing a tracking system in the air “did not rely on a system that was 100 percent self-reporting from each airplane,” he said, adding that similar capabilities are needed for space. “We need an independent way, a la air traffic radar, to have that transparency to see what people are doing in space.”

As the previous commander of 14th Air Force at Air Force Space Command, retired Lt. Gen. Susan Helms had access to the most advance radar the U.S. has to offer, but said that often even that wasn’t enough.

“The [Defense Department] has radars, but they are not promulgated to the point you can get that kind of actionable knowledge quickly in a time dominate manner,” she said.

Helms recalled one story of having two satellites pass within close proximity of each other, but not knowing if they had collided until after the fact. “It’s not like a TV explosion in the sky,” she said. “If they do collide, you don’t know that unless you take a look with your radar.”

Comparing it to weather prediction, Helms said knowledge of possible satellite collisions should be like hurricanes: you know they’re coming well in advance and have plenty of time to prepare.

Instead, in the case of the near-miss, “this was the tornado that came out of nowhere,” she said. “I’d rather have a hurricane and not a tornado. I wish I had world coverage radars so I could get an assessment of the possibility of collision on this object now.”

But collecting data is just the first part of the battle. Better analysis and processing are needed to turn the raw data into something useful, Greiman said.

He said there were more than 670,000 conjunction warnings in 2014 alone, and noted that the Air Force’s plans for an advance tracking system known as Space Fence will soon add more raw data to the pile. “We simply have to come up, if nothing else, with a better way of doing measurements and predictions of conjunctions,” Greiman said.

Even if data collection and analysis are excellent, there’s still a legal question of who exactly can force a change in orbit.

“In the United States we don’t have an agency that has the authority to tell a space operator to move their satellite out of the way of a piece of degree,” said P.J. Blount, an adjunct law professor at Montclair State University. “I think this jurisdiction question is going to be an important one.”

Private companies might be willing to take more risks than the U.S. government would like, Blount explained, by weighing the cost of a collision versus a loss of satellite lifespan due to having to maneuver the craft.

It becomes an even more uncertain issue for the international community. “We have the possibility of conjunction, not just between U.S. assets, but a U.S. actor and an actor from another nation,” Blount said.

Travis Blake, senior manager at the Advanced Technology Center for Lockheed Martin Space Systems, said he believes the idea of space being very large has hindered work on SSA somewhat, as most believe the possibility of a collision wasn’t realistic. “The ability to have to manage what’s up there has not had to come along as quickly as it did in the maritime and the air traffic world,” he said.

It’s a bit of a misconception, however, Blake argued, as while space is very large, certain areas like geosynchronous orbit are becoming very crowded. “What we’re seeing now in the space era is we have taken this very large portion of space, and we’ve kind of constricted it down to these corridors that we operate in,” he said.

The various “corridors” used by spacecraft could further complicate issues, Helms said, as different areas of space might require different rules for avoiding collision, such as changing how much of an empty “bubble” each object needs around it. “The mode you use for [LEO] is not the model you want to use for GEO,” she said.

Greiman said there needs to be a central authority for space traffic management, an agency that could tell an operator, “Your cubesat has got a three-year lifecycle. Show me in your launch and registration plan how at three years and six months you’re going to de-orbit that cubesat, or take out an insurance policy?”

For his part, Greiman put his support behind transferring SSA duties from the Air Force to the FAA, an idea that has been widely discussed in government circles. “The FAA in my opinion…is not just an option, it’s the only option,” he said. “It’s the only agency that can put safety as number one and has the government association to protect the information.”

Nield, the FAA administrator, said his agency is ready. “We’re in the process right now of figuring out what this ought to look like,” he said. “We’re very excited about getting this started.”

The FAA would need three things to perform space traffic tracking properly, Nield said. “The authority to distribute the information just like the [Defense Department] has today, immunity from lawsuits just like DoD has today, and the resources to do the job because of course we’re not currently funded to do that duty,” he said.

Regardless of how better SSA eventually develops, it’s critical that it does, Nield said.

“It’s very important for those of us in the business to periodically step back and think for a minute on how dependent we have become as a nation and as a society on space and spacecraft,” he said. “To the extent that we have more and more congestion, more and more collisions, there’s a very real possibility that individual spacecraft and even the entire regions of space that we count on so much will at some point become unusable. Pretty scary thought.”

SpaceNews.com

Source: Space News

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Many questions, few answers when it comes to space traffic management, experts say

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