It Just Got A Lot More Crowded In Low-Earth Orbit
Updated: Nov 18, 2021
Astronauts and experiments on the International Space Station work to make life better on Earth and help humanity explore deep into the cosmos. Credits: NASA
There was an emergency on the International Space Station on Monday. The crew was told to shelter in the Soyuz and Dragon capsules, with the warning that the facility was going to pass through a cloud of debris. The debris cloud was the result of a test of the Russian Federation’s anti-satellite (ASAT) system, without warning to other nations. After a local warning to airmen, a missile was launched from the ground in Plesetsk, and destroyed a Russian satellite, Cosmos-1408, that had been in orbit for almost four decades by a high-speed impact. Massing about two metric tons, the satellite was obliterated into at least 1500 trackable pieces, and likely many times more than that too small to track.
Unfortunately, it was not the first time that an ASAT test has fouled low-Earth orbit (LEO). Two and a half years ago, India performed a similar test, making it the fourth nation (after the US, USSR/Russia, and China) to demonstrate such a capability. The Chinese destroyed their own defunct weather satellite in 2007, and the ISS had to perform a maneuver to dodge a piece of it just a few days ago. A few months after the Chinese test, the US blew up an aging spy satellite, out of a stated concern that the toxic rocket propellant in its fuel tank would contaminate populated areas where it entered, but because it was already entering, the debris entered as well.
Credit: Space Station images
But the debris from the Chinese, Indian, and now Russian tests is long lasting, because its altitude is high above the atmosphere, where there is little drag to slow it down and enter it. So it is a problem that is not going to go away any time soon, and as long as it remains in orbit, it will be a hazard not just to the ISS, but to every satellite in LEO, including the hundreds and thousands that are currently being deployed by SpaceX and other companies to provide global Internet service.
LEO velocities are about 27,000 km/hour, which means that potential closing velocities between the debris and valuable satellites going in the opposite direction could be as high as 54,000 km/hour. The impact energy goes up as the square of the velocity, so a head-on collision can be very large. Things as small as paint chips have damaged the windshield of the Space Shuttle orbiter, and a window on the ISS was hit this past spring.
But the real problem is that incidents like this increase the likelihood of the “Kessler syndrome” (after NASA researcher Don Kessler) in which each collision spawns a cascade of collisions, to the point that it becomes almost impossible to get through the region without being hit. This would effectively close off space to humanity until we come up with a way to clean up the mess.
Reaction to and criticism of the event was swift, with the US State Department issuing a statement at a press briefing, followed by one from the Pentagon. Later in the day, NASA administrator also issued a statement of condemnation, saying that he was “outraged by this irresponsible and destabilizing action. With its long and storied history in human spaceflight, it is unthinkable that Russia would endanger not only the American and international partner astronauts on the ISS, but also their own cosmonauts. Their actions are reckless and dangerous, threatening as well the Chinese space station and the taikonauts on board.
All nations have a responsibility to prevent the purposeful creation of space debris from ASATs and to foster a safe, sustainable space environment."
Today, the Secure World Foundation issued a harsh statement as well, calling for the UN to work toward an agreement on how to establish norms in space, to avoid this unacceptable behavior. Russia finally did admit to doing it, while claiming that the ISS was in no danger.
NASA’s astronaut Jack Fischer snapped this shot of a glowing green aurora during Expedition 52 aboard the ISS. Credit: Space Station images
What is unclear is not just why they did such a test, but why they chose to do it on Monday. More than one commenter has noted that it comes as Putin’s government is stirring up trouble on the planet below, flooding refugees into Poland, massing troops on the Ukrainian border, and threatening to cut off energy supplies to western Europe. But it’s not clear even in this context what the purpose would be, though it could be considered a potential “shot across the bow” to warn other spacefaring powers not to interfere with more Earthly events.
It would have been ironic if it had in fact damaged the Russian portion of the ISS, or even injured or killed a cosmonaut, and it seems like a strange act when Russia has assets in LEO as well. But this raises a disturbing possibility. Russia’s space program has been in decline of late. Perhaps Putin is envious of all of the commercial activity that Russia is not participating in, and has decided that if Russia can’t play the game, he wants to tip over the board for everybody. Let’s hope that isn’t the case, because he is certainly capable of doing it.