Photo it: Space shelter around the earth, the planet’s curve going against the white space of the universe. Maybe a little Strauss is playing. An orbiting satellite comes in, its boxing body with solar panel wings extending out on all sides.
Unfortunately, that satellite is not alone. Years earlier, an abandoned Russian rocket group exploded into orbit after leaking propellants mixed together. Or missiles were tested against a satellite, exploding a spaceship and scattering its parts around the planet. Or a satellite was cut free from its rocket by an explosive charge, throwing one bolt into orbit.
And as our satellite arrives, that bolt, or chip of paint, or broken strut, is approaching a spicy distance. Objects orbiting the earth move impossibly quickly – the maximum is 17,500 miles per hour (28,163 kph), but 5 miles per second may be easier to establish. consider.
The debris and the spacecraft usually overlap. Failure to do so – if the satellite is hit by that debris – could result in damage to tens of millions of dollars worth of hardware.
The odds are starting to shift. More satellites are being launched, and the number of active spacecraft is expected to rise tenfold or more in the coming years. More anti-satellite weapons testing has scattered more debris, and, in 2009, the first crash between an operational spacecraft and a redundant one.
And each new collision increases the amount of debris in orbit, which NASA currently estimates is more than 8,000 metric tons, and covers more than 500,000 pieces larger than a centimeter. in diameter.
This multiplication is partly caused by businesses that are camping on the business of making more money in orbit by launching more satellites. And now, a business is emerging to stop space waste by repairing or removing dying satellites before they become part of the problem.
Astroscale plan to help satellites to end their lives
One of these companies is Astroscale, a company founded in Japan in 2013 by CEO Nobu Okada, with offices in the US and UK. He is about to do his first major experiment to show that this is possible. On March 22, the company launched a 200 kg spacecraft on a Russian rocket Soyuz. It’s called ELSA-d, for Astroscale-display End of Life Services.
All the satellites finally stop working. Their batteries lose their ability to recharge, propellants run out, they are hit by orbital debris, or like any other device, they just break.
Satellites flying in low ground orbit within 2,000 miles of earth, the busiest area around the planet, will eventually be pulled into the atmosphere by gravity. Current international standards require these satellites to be designed to fire in 25 years – but it is becoming increasingly clear that they are not fast enough to reduce the risk of collisions. Even five years, the level of volunteering undertaken by many satellite operators, could be too long to prevent dangerous congestion.
Insert Astroscale: When satellite life is over, Astroscale would like to pay for satellite operators to send a spacecraft to zip up, plucking the obsolete satellite and dragged it down to a lower orbit where it fired even faster.
To prove that possible, Elsa-D has two spacecraft in one. In space, it emits a target satellite with a special magnetic plate attached, and moves to extract it. It then releases the target again, but this time in a spin, as damaged satellites can go up through space. If the diving satellite can splinter, the final display involves moving around the target and being monitored by sensors.
None of this is simple – it requires smart sensors, software that can respond in real time, and robots and tight motion systems.
Some history of service in the area
ELSA-d is among the first private companies to help a different spacecraft in orbit, largely because most satellites are not designed for it. Getting up to the point is so expensive and so dangerous that engineers don’t count on their ability to refuel or repair – everything is built to last.
“The International Space Station and Hubble are in fact two notable exceptions to the general rule that most spacecraft are upgraded for assembly, integration, ground testing – no entry or ever a visit or a change in space, ”says Ben Reed, who leads the space servicing research at NASA’s Goddard Space Center.
That’s a big problem: The astronauts who repair the ISS or the Hubble space telescope are capable of making up in ways that robots can’t – on the last mission to repair the Hubble spectrum in 2009, an astronaut to use brute force to handle after one of its replacement bolts was peeled off.
However, robots can operate with inoperable targets. Last year, Northrop Grumman unveiled a spaceship called the Mission Extension Vehicle, or MEV. His target was a 19-year-old Intelsat communications satellite, running out of fuel and the prospect of losing the ability to keep itself in the right place. The MEV was able to fly to the satellite and insert a docking probe into an unused engine port, plucking it.
Now, the MEV can use its own engines to keep the satellite in the right place for another five years – a huge financial benefit for Intelsat, which paid more than $ 120 million to build that satellite in 1999. , and it will now be possible to delay relocation. e. Intelsat has hired Northrop to use a second MEV to extend the life of another satellite, with docking expected in the coming weeks.
The future of satellites is ready for repair
Circulating inoperative satellites to a position using the MEV model, for all its benefits, is still very expensive: It requires a dedicated spacecraft, rather than a more cost-effective vehicle that can service to one spaceship before moving on to the next.
NASA’s Reed is developing a mission called OSAM-1 with that idea in mind. It plans to feature several space service technologies in 2022, including the Landsat-7 refueling, a U.S. terrestrial satellite image launched in 1999.
Landsat-7 was not designed for orbital crops. The NASA spacecraft must use robotic devices to cut off a thermal shield and remove metal wires that secure a cap on the fuel valve, using a refueling device to pump it into a new exciter. , and then try to shut it all down again so that the satellite can continue on its path.
This type of technology will be essential for cleaning old debris in orbit, from dead satellites to discarded rockets. To make things easier in the future, satellite designers need to design their vehicles with features such as accessible compartments and refueling ports. Lockheed Martin said in February that it would be designing the next generation of GPS satellites for servicing, but that option is promising.
“It’s kind of a chicken and an egg,” says Reed of NASA. “There is no public servant. Why would anyone design their satellite to be in service if there is no server? ”
Space safety advocates want to start with something as simple as a sticker – a standard decal with symbols that can be an optical target for an approaching satellite, without adding much mass.
“The hardest part of the autonomous mission is rendezvous and grapple – the time in which we are about two meters away from something else floating free, and by the way, no there is no tree, we must get hold of it. somewhere it won’t break, there are no lanterns or LEDs or retroreflectors, ”says Reed. In contrast, the spacecraft arriving at the ISS detects reflective targets in advance on the space station to accurately determine how far they are approaching.
The Astroscale playground is one step further: It is hoped that satellite operators will use similar symbols, but on a magnetic metal plate that will make grip simpler. OneWeb, a company that builds a large satellite constellation in low-earth orbit, has said it will install similar fixtures to all of its spacecraft.
Government mandate for sustainability?
“I will pay with the ton if they can remove debris,” General David Thomson, commander-in-chief of the U.S. Space Force, told reporters last week when asked if they should the government pays companies to take debris out of orbit.
Maybe that’s the way for a place service to become a real business, and avoid the chicken-and-egg problem of who invests first in expensive technology and see their real benefits as distributed objects. Astroscale and other companies making that investment hope that governments will push satellite operators to develop higher standards, but also become customers find a way, as they have in sending satellite launch, human space light, and now lunar exploration.
“We know that sustainability in orbit is a big business,” Charity Weeden, Astroscale’s head of public policy, told Quartz. “It opens the door to access on-orbit services – tow trucks, petrol stations, tool shops and more. It gives operators choice and flexibility, continuity of service, and certainty in the face of incoming regulatory requirements. It helps protect your investment and in doing so, protects the orbital environment. ”
White House Office of Science and Technology Policy
But it will not be easy to get there, with turf wars who will make those decisions and how persistent it is within national governments and global institutions. “I don’t see it as a linear approach, unfortunately,” Weeden warns, but notes that there have never been so many different NGOs, trade bodies and governments involved in debating the right way to deal with space debris. That conversation, however, will be guided by what technicians are capable of proving – which is why Elsa-D and similar public and private missions are so important.
“We are in the place of those conversations, because we are both proposing policies and improving governance structure, but also doing something about it,” Weeden says. “There’s a lot to talk about, but not much to do. We open the action case. ”