Wednesday, November 24, 2021

Blown-up satellite pieces circling Earth shown in scientist's unsettling simulation
"It wasn't a good outcome. It was never going to be a good outcome."

By Mark Kaufman on November 20, 2021

A simulation of space debris from the blown-up Russian satellite Cosmos 1408.
 Credit: Screenshot: YouTube / Hugh Lewis

Russia blew up a big, derelict satellite in an objectively terrible area of space.

The space community is heated, disappointed, and frustrated by the Nov. 15 missile test that transpired some 300 miles above Earth. The explosion of the around 4,850-pound satellite created a cloud of fragments that triggered an emergency response on the relatively nearby International Space Station: Astronauts awoke and hastily prepared to evacuate the threatened space outpost.

A simulation of the orbital debris, created by Hugh Lewis, a professor of astronautics at the University of Southampton who researches space debris, shows the ring of problematic junk orbiting Earth.

"We're going to see consequences from this particular event for the next few decades," Lewis told Mashable. "It wasn't a good outcome. It was never going to be a good outcome."

"There wasn't a worse target to aim for with respect for human spaceflight," Lewis added. "It wasn't a good outcome. It was never going to be a good outcome."

It's a bad outcome because humanity is adding more space debris into increasingly crowded orbits around Earth much faster than it's removed (satellites below altitudes of some 1,200 miles above Earth gradually fall into the atmosphere and burn up, a process called atmospheric drag). Already, spacecraft today have to maneuver to avoid collisions with other debris. Earlier this November, threatening debris from a Chinese weapon test in 2007 forced NASA to move the space station. The U.S., Russia, and China have all destroyed satellites in space, resulting in clouds of space junk.

The two simulations below show the new debris cloud as it travels around Earth and spreads out. Already, there are some 1,250–2,500 pieces of known, trackable debris, and certainly thousands of tiny undetectable objects. The consequences are long-term.

"This debris field will expand in size and spread in a ring around the Earth that will likely remain on orbit to threaten other space objects for years to come," the Secure World Foundation, an organization promoting sustainable and peaceful uses of space, said in a statement. "Regardless of rationale, to deliberately create orbital debris of this magnitude is extremely irresponsible."

Russia claims its latest missile test "did not pose a threat" to the space station.


To create a realistic view of the evolving debris ring, Lewis used a computer program that modeled the breakup of the satellite, and then simulated how the fragments would move around Earth. The debris cloud spreads out, with some fragments moving to higher and lower altitudes — hence the potential danger to the space station. (Things, however, have largely returned to normal aboard humanity's oldest and largest space outpost.)



The looming problem is that space debris spawns more space debris, specifically by increasing the odds for more collisions. In 2009, for example, the defunct Russian satellite Cosmos 2251 slammed into an Iridium communication satellite, creating some 2,000 pieces of debris four inches or larger along with countless tiny fragments. In 2013, astronaut Chris Hadfield spotted a "bullet hole" in a space station solar panel — from either space junk or a small meteorite. Humanity has already put large amounts of debris into orbit around Earth, and its impacts are serious and growing. "Spent rockets, satellites, and other space trash have accumulated in orbit increasing the likelihood of collision with other debris," NASA wrote in 2016.

Over the coming three or four decades, if enough debris eventually accumulates, a runaway cascade of collisions will ensue, an extreme event dubbed the "Kessler Syndrome" by Don Kessler, a former senior scientist for orbital debris research at NASA. In 2018, Kessler expressed worry to Mashable about SpaceX's plans to launch thousands of Starlink satellites into Earth's orbit. Already, the private space company has launched over 1,800 satellites, with plans for thousands more. SpaceX has plans to deorbit failing or old satellites into Earth's atmosphere, but the sheer number of satellites still means a lot of objects zipping around the planet. Among other mega-satellite constellations, Amazon plans to launch over 3,200 satellites, too.


The latest satellite blow-up itself isn't nearly "end days" for the fleets of satellites monitoring weather, the planet, and providing crucial communications. But it shows that civilization is now in the incremental, slow-moving process of increased collisions.

"It's a very insidious type of process," explained Lewis. "What we see is not this sudden transition. We're seeing gradual change."

Gradual change, unfortunately, means a heightened risk for humans aboard the space station. One of the most serious emergencies on the station would be a "rapid depress" of air pressure, which could happen during a collision. (Fortunately, the station's modules do have some protective shields.)

SEE ALSO: How the space station flipped out of control—and why that's a big problem

There are plans and ideas to catch and remove large, defunct satellites and rocket parts — the kind of debris that might be too high to naturally fall into (and burn up in) the atmosphere — from Earth's orbit. The European Space Agency has paid a company to capture part of an old rocket with a crab-like apparatus, and researchers tested a harpoon that catches space debris. But these won't be deployed, at least in large numbers, any time soon.

To clean up Earth's space neighborhood, the best option is closely monitoring spacecraft (to maneuver and avoid collisions), ensuring old satellites are well-placed to burn up in the atmosphere, and promoting international coordination in launching sprawling satellite constellations. Satellite companies, like Iridium, SpaceX, and Amazon, certainly have a big financial incentive to avoid collisions, which would lead to more collisions and loss of expensive (and expensive to launch) inventory. "It's in the companies' own interest to operate in a clean way," noted Lewis.

But it's in no one's interest to unexpectedly blast a satellite into thousands of fragments in a region of space where people live. After the early morning missile strike, NASA had little time to react, or even try and maneuver the station. So the agency awoke the astronauts and prepared for the worst.

"That shows you how reckless the act was," said Lewis.


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