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Home / Science / 3% of SpaceX Starlink satellites may fail in orbit around the Earth

3% of SpaceX Starlink satellites may fail in orbit around the Earth



  • SpaceX has launched nearly 800 Starlink Internet satellites, and a constellation of 42,000 spacecraft is planned for this decade.
  • The company says its satellites can avoid ion-powered collisions, but about 3% seem to have failed because they no longer maneuver in orbit, according to astronomer Jonathan McDowell.
  • Unable to maneuver orbital satellites can crash into other spacecraft and form dangerous space debris.
  • A failure rate of 3% is not so bad, says McDowell, but if this number is maintained for the entire planned SpaceX fleet, it could kill more than 1,200 satellites.
  • Visit the Business Insider homepage to learn more.

SpaceX launches dozens of satellites into space to implement Starlink, the constellation of spaceships surrounding the globe that transmit affordable high-speed Internet across the globe.

So far, the scheme envisioned by SpaceX founder Elon Musk seems to be working. The aerospace company even plans to open a public beta test in the northern United States and southern Canada. Musk wrote on Twitter on October 8, possibly over the next few months.

“Other countries should follow as soon as we get regulatory approval,”

; he added.

However, the unprecedented project left a mark on the seemingly next spacecraft. All satellites are designed to maneuver them in space with an ion engine and even deorbit themselves back to Earth. But satellites with malfunctioning communications systems or propulsion systems can fly uncontrollably and pose a danger to other satellites and even astronauts orbiting the Earth.

SpaceX launched its first batch of 60 prototypes in May 2019, and to date has flown 775 Starlink Internet satellites. But so far, about 3% of these spacecraft may have failed, according to data collected by Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics.

“I would say that their failure rate is not extraordinary,” McDowell told Business Insider. “It’s no worse than anyone else’s failure rates. The fear is that even the usual failure rate in such a huge constellation will end up with a lot of bad space debris.”

Some of these failures may be intentional tests, but how many (if any) are unknown is well known because SpaceX has not released such information. As a result, astronomers such as McDowell have analyzed satellite motion data from SpaceX and the US government, showing which Starlink satellites fell back to Earth and which did not maneuver. (The 3% failure rate does not include the 45 satellites that SpaceX is known to have deliberately de-energized.)

satellites starlink flat pack stack payload falcon 9 rocket spacex twitter D7THAABVUAATipL

The first batch of 60 high-speed Starlink Internet satellites weighing about 500 pounds is packed in a stack before their launch on the Falcon 9 rocket on May 23, 2019.

SpaceX via Twitter



SpaceX has permission from the US government to launch nearly 12,000 Starlink satellites, although it is invited to launch another 30,000 for a total of nearly 42,000. -any launched by mankind. If 3% of the maximum planned constellation of Communication fails, it could mean 1,260 dead, 550-pound satellites the size of a table orbiting the planet.

According to the European Space Agency, as of February there were about 3,200 disabled satellites in Earth orbit. Many of these dead spaceships regularly threaten to collide with others and create a space debris crisis. This week, for example, satellite trackers marked a “very high risk” of a close passage between a dead satellite and a dropped rocket hull, with one company calculating a 10% chance of a collision. (In the end, they didn’t collide.)

SpaceX claims that its satellites will naturally become de-energized or burn up in the Earth’s atmosphere if their propulsion systems fail. But on the Starlink website, this process can take up to five years. Meanwhile, non-existent satellites rotate around the Earth faster than a bullet, and no one diverts them from other spacecraft that may fly in their path.

SpaceX did not accept Business Insider’s request for comment. However, by applying to the Federal Communications Commission, SpaceX mitigated the risk, saying it “considers unacceptable satellite failure of 10 to 5 percent, and even a rate of 1 percent is unlikely.”

If 1% of its satellites actually fail without maneuverability, the company said, “there is about a 1 percent chance in a decade that any failed SpaceX satellite will collide with a piece of tracked debris.”

The company also said its practice “effectively eliminates the possibility that such bets will ever occur.”

Dead satellites can collide and create a space debris crisis

india anti-satellite missile asat test mission shakti space debris debris cloud cloud field orbit simulation march 2019 analytical graphics inc 2

Modeling of space debris created as a result of the Indian test of anti-satellite missiles “Mission Shakti” on March 27, 2019.

Analytical Graphics Inc.



However, SpaceX is not alone, trying to launch a large number of Internet satellites. OneWeb has already launched 74 satellites for the planned constellation of 48,000, and Amazon is aiming to launch more than 3,200 for its Kuiper fleet. It is unclear how many dead satellites these constellations can also leave in orbit.

Because no one can maneuver them, the failed satellites sometimes rush to other spacecraft, including the International Space Station and the astronaut crew.

Even if a satellite crashes into another satellite without people on board, it can create dangerous conditions.

“We’re replacing two satellites with essentially two fractional explosions,” said Dan Chaperley, CEO of satellite tracking company LeoLabs, in January. That month, two dead satellites nearly crossed and exploded in hundreds of thousands of wreckage.

experiment of collision of satellite fragments explosion simulation

The projectile strikes the model of the spacecraft during NASA Air Force tests designed to simulate space debris collisions.

Arnold Engineering Complex / Air Force



This would not be the first such explosion, and it will take a long time to exacerbate the garbage problem. In 2007, China tested an anti-satellite missile by blowing up one of its own weather satellites. Two years later, an American and a Russian spacecraft collided by accident. These two events alone increased the amount of large debris in low-Earth orbit by about 70%. India conducted its own test of anti-satellite missiles in 2019, and it is estimated that the explosion formed 6,500 fragments larger than an eraser

In all, more than 500 such “fragmentation events” have created nearly 130 million pieces of debris in Earth orbit. These pieces of debris revolve around the planet at speeds in excess of 17,500 mph, or about 10 times faster than a sphere.

This is a problem not only of robotic spacecraft, but also of those in which humans are. Just last month, a piece of garbage piled up a mile from a space lab the size of a football field. To avoid a collision, mission controllers fired the propulsion of an attached Russian cargo spacecraft to maneuver the station without causing damage. Three crew members locked themselves inside the ISS segment with the Soyuz spacecraft so that they could escape if the wreckage hit.

A space shuttle is trying to trash the wings of the trash into a hole damaged by NASA

The space debris got into the radiator of the Endeavor spacecraft, found after one of its missions. The inlet is about 0.25 inches wide and the outlet is twice as large.

NASA



If the problem of space debris becomes extreme, the chain of collisions can get out of control and surround the Earth in a virtually impassable field of debris. This possibility is known as Kessler’s syndrome, after Donald J. Kessler, who worked at NASA’s Johnson Space Center and calculated in a 1978 article that it could take hundreds or even thousands of years to make spaceflight safe again.

“This is a long-term effect that has been going on for decades and centuries,” said Ted Muhlhaupt, who manages the analysis of The Aerospace Corporation’s satellite system, Business Insider. “Anything that makes a lot of rubbish will increase that risk.”

A huge number of objects in Earth orbit may already have an effect similar to Kessler, as described last week by CEO of Rocket Lab Peter Beck.

space debris satellites of the Earth's orbit

Illustration of space debris. Satellites and garbage have no scale.

ESA / ID & Sense / ONiRiXEL



“It has a huge impact on the launch site,” he told CNN Business, adding that the missiles “should try to break through between them.” [satellite] constellation “.

Starlink is already a danger to space debris

SpaceX has barely launched 2% of the planned constellation, but it is already approaching.

In September 2019, the European Space Agency had to maneuver one of its spacecraft at the last minute to avoid a possible collision with the Starlink satellite. The chance of this crash was 1 in 1,000. Although it may seem low, NASA regularly moves the ISS with odds of 1 in 100,000.

ESA said it had to relocate its satellite because SpaceX “had no plans to take action.” SpaceX said it missed ESA emails about the problem due to a “bug” in its communications systems.

spacex starlink internet satellite spaceship solar panel lattice terrestrial orbit illustration 00002

Illustration of the satellite Internet constellation “Spacelink” in orbit around the Earth.

SpaceX



In general, such approaches seem to occur more frequently.

“Recently, we’ve seen a sharp rise in the number of connectors,” said Dan Altrogge, an astrodynamicist at Analytical Graphics, Inc., where he uses software that evaluates connection data since 2005, Business Insider said. “And it seems to fit in very well with the new spacecraft with the big constellation that has been launched.”

When launching new satellite constellations, regulators such as the FCC may need to estimate how many dead spacecraft they are willing to accept.

“What is the allowable failure rate?” McDowell asked. “It’s maybe I’m not competent to have an opinion.”




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