Post by kiwithrottlejockey on Apr 22, 2017 14:43:54 GMT 12
from The Washington Post....
Thousands of tiny satellites are about to go into space
and possibly ruin it forever
Space is a mess.
By AVI SELK | 7:00AM EDT - Friday, April 21, 2017
Astronaut Thomas Pesquet of the European Space Agency photographed the Rocky Mountains from the International Space Station in January.
— Photograph: Thomas Pesquet/Agence France-Presse/Getty Images.
HALFWAY THROUGH the European Space Agency's new film, we're at the part where — if this were some happy space documentary from yesteryear — Carl Sagan might be giving us a tour of a distant galaxy.
But it's 2017, Sagan is dead, and this is a film about space trash. So six minutes in, we're stuck a mere 800 miles above Earth, watching a wasp swarm of defunct satellites whip around the globe to a frenetic soundtrack that sounds like the end of “The Dark Knight”.
It's a dramatic simulation of what low Earth orbit looks like today. You can even watch it in 3-D. Because the European Space Agency really, really wants you to pay attention to the space debris problem.
The problem is about to get worse, experts say, as cheap, tiny satellites are shot through the stratosphere in unprecedented numbers.
Worst-case scenario: a massive, unstoppable, chain-reaction traffic wreck above our heads. So much for escaping Earth to distant galaxies.
The short film “Space Debris: A Journey to Earth” was screened this week in Germany at the world's largest annual gathering of space-debris experts.
The news from space was not great.
Hundreds of thousands of bits of space junk are orbiting Earth, according to NASA. These include tiny paint flecks that can take out a space shuttle window, and some 2,000 satellite shards left by a collision of Russian and American satellites several years ago.
In Germany, the audience was shown a slide from another depressing space film, “Gravity”. The part where the International Space Station is destroyed in an avalanche of space trash.
“There were many mistakes in that movie; I will not go through that,” ESA Director General Jan Woerner said. “But the effect, as such, is a very serious one.”
Woerner cut to video from the real International Space Station, which has not yet been destroyed.
Bobbing around in zero gravity, astronaut Thomas Pesquet described what the space station crew has to do when a piece of debris whizzes past: Climb into an escape shuttle, wait and hope.
“This happened four times,” Pesquet said. “In my own interests, let me wish you a successful conference.”
Picture: European Space Agency.
Then it was on to a keynote speech from retired NASA scientist Donald Kessler, known for coming up with an apocalyptic space-crash theory called the Kessler syndrome — or “orbital Nagasaki”, as a researcher once described it to The Washington Post.
Basically: A thing hits another thing at 25,000 mph or so. Those things then explode into more things, which hit yet more things, initiating a catastrophic chain reaction of collisions that makes low Earth orbit totally unusable.
Kessler predicted this in the 1970s, when space had fewer things in it. At this week's conference, he previewed a new study he worked on that found “a statistically meaningful number of satellites” that have been damaged by debris.
And an ESA official described a recent study finding that a particularly crowded region of space has already become unstable, which he worried could foretell Kessler's doomsday scenario.
The bad news didn't stop there.
As satellites get smaller and cheaper, more and more of them are going into orbit to potentially smash into each other.
In February, The New York Times reported, India launched 104 tiny satellites into space from a single rocket.
It was a world record, though one not likely to stand for long.
In all of human history, ESA's debris chief said at the conference, about 7,000 spacecraft have left Earth. He pulled up a slide of 12,000 new satellites set to go up soon, announced by companies such as Samsung and SpaceX.
Many of these — like the batch India sent into space — are nano-satellites: tiny, motorless machines that promise to revolutionize communications.
They're simple enough to make that grade school students in Arlington, Virginia, put one together for a class project. Once in orbit, they fan out into wide constellations, outperforming their bulkier ancestors.
But these tiny satellites have big problems, according to experts at the conference. There will be lots of them, for one thing. And since they can't navigate, they'll keep careening through space long after they've stopped working and are thus more likely to collide with other things.
Hugh Lewis, an aerospace researcher with the University of Southampton, spoke at the conference about a dire computer model his team ran. They simulated the effects of 270 nano-satellites launched into space each year for 50 years — a realistic assumption, Lewis said, as more than 100 a year are already going up.
He projected the results of the simulation onto the wall; the chance of space collisions more than doubled with the tiny satellites in play.
Lewis noted that “mega-constellations” of satellites aren't necessarily bad. He said they have the potential to provide affordable communications to the half of the world that lacks such technology.
But other experts at the conference noted that voluntary guidelines to mitigate space debris (bring your dead satellite out of orbit within 25 years, for example) often go ignored.
“No one has found an ideal solution for cleaning up the junk that's already there,” Rachel Feltman wrote for The Washington Post last year.
And if the next Space Age only adds more of it, low Earth orbit could resemble something even worse than a dramatically scored wasp swarm by the time the ESA makes a sequel to its space-trash film.
• Avi Selk is an American-Canadian nomad. He reported for the Dallas Morning News from 2009 until December 2016, when he joined the general assignment desk at The Washington Post.
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• VIDEO: Watch man-made objects journey from the outer solar system back to Earth
• Space trash is a big problem. These economists have a solution.
www.washingtonpost.com/news/speaking-of-science/wp/2017/04/21/thousands-of-tiny-satellites-are-about-to-go-into-space-and-possibly-ruin-it-forever