Recently, the news that the Chinese space station has twice urgently avoided the "Starlink" satellite has aroused widespread concern and heated discussion.
According to the Global Times reported on the 28th, the official website of the United Nations Committee on the Peaceful Uses of Outer Space recently released news that on December 3, the Chinese Permanent Mission to the United Nations and other international organizations in Vienna sent a note verbale to the Secretary-General of the United Nations, informing them that the Starlink satellite launched by the US Space Exploration Technology Corporation (SpaceX) has approached the Chinese space station twice this year, posing a threat to the lives and health of astronauts on the Chinese space station.
Chinese Foreign Ministry spokesman Zhao Lijian also confirmed at a regular news conference on December 28 that in July and October this year, SpaceX launched a starlink satellite that approached the Chinese space station twice. During this period, Chinese astronauts are on missions inside the space station, and for safety reasons, the Chinese space station has taken emergency collision avoidance measures.
Screenshot of information posted on the official website of the United Nations Committee on the Peaceful Uses of Outer Space
According to foreign media reports on the 28th, space agencies and a number of space experts and astronomers have said that the "star chain" satellite has now become the "biggest threat" in space, not only because of the large number of "frequent trouble", but also ignore the warnings of relevant agencies to "act willfully".
Worse still, behind all this is the rapid development of commercial space in a "regulatory vacuum". European Space Agency Director Aschbach warned earlier this month that Musk was working on space rules because the "starchain" was so large that it would be difficult for regulators or competitors to catch up.
Nearly 1,800 satellites "cause trouble" 2,100 times a week
Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, said that due to the number and speed of satellite launches, the avoidance operations taken to reduce the risk of space collisions are becoming more frequent, and the "star chain" is an "important factor" in this.
SpaceX founder Elon Musk proposed the Starlink program in 2014 to launch 12,000 satellites into low-Earth orbit to establish a satellite Internet service covering the world, and the company is ready to add 30,000 more satellites, bringing the planned number of launches to 42,000. In 2019, the company sent the first 60 StarLink satellites into space. According to statistics, although the company has only launched nearly 1800 satellites so far, it has caused as many as 2100 close contact events per week.
Hugh Lewis, a space debris expert at the University of Southampton in the United Kingdom, said that the number of satellites in space has increased dramatically due to SpaceX's "Starchain" program, and the number of close-up encounters has also increased sharply in the past two years.
Contents of the medium inquiry part
"I looked at data from the first launch of the Starlink satellite in May 2019. Since then, the database has more than doubled the number of spacecraft proximity events, and now our situation is that at least half of the spacecraft proximity events are related to the 'star chain'. Lewis said in an interview in August. Among them, the "Starlink" satellites have close contact with each other up to 1600 times a week, and other satellites in space have close contact with each other 500 times a week.
However, this issue will be further complicated in the future. So far, even though SpaceX has only launched 1,740 satellites, Lewis' calculations suggest that once all 12,000 satellites of SpaceX's first generation are launched, the Starlink satellites will "participate" in 90% of all close encounters.
A constellation of star-linked moons in the sky.
In addition to SpaceX, many companies are also "catching up". The Satellite Industry Association estimated last year that the number of commercial spacecraft in orbit will exceed 100,000 by 2029.
Automatic collision avoidance failure? StarLink security and reliability "debatable"
Lewis pointed out that due to its near-monopoly status, the impact of the "Starlink" on the safety of low-Earth orbit operation is increasing. But given that SpaceX has only been in the field of satellite operations for two years, its safety and reliability are "debatable."
"We're faced with a situation where most of the activities we see will involve 'Starchain'," he said. They used to be a launch service provider and are now the world's largest satellite operator, but they've only been doing it for two years, so there's a certain lack of experience. ”
Most critically, SpaceX's Starlink satellites rely on an automatic collision avoidance system that keeps its fleet of satellites away from other spacecraft. However, the technology seems to have gotten them into trouble more than once.
According to reports, on September 2, 2019, the "Starlink-44" satellite almost collided with the European Space Agency's "Fengshen" Earth observation satellite, almost causing a tragedy. At that time, the satellite descended to an altitude of 320 kilometers, testing its automatic de-orbit technology, only to get close to the "Fengshen" satellite that was operating at this altitude. SpaceX's proud automatic collision avoidance technology didn't seem to work, and the European Space Agency had to urgently change the "Wind God" to avoid the "Starlink-44" satellite.
On September 2, 2019, the Starlink-44 satellite nearly collided with the European Space Agency's Fengshen Earth observation satellite. Picture according to the European Space Agency
In April, a Starlink satellite nearly collided with a similar satellite of the British company OneWeb, at one point only 57.9 meters apart. The U.S. Space Force's 18th Space Control Squadron issued a "red alert" at the time, and OneWeb subsequently accused SpaceX of shutting down the automatic collision avoidance system on the Starlink satellite.
In addition, automatic collision avoidance systems can sometimes cause more problems. For example, when there is a danger warning, the satellite will automatically change its orbit and enter a new orbit that other satellites cannot predict. However, the satellite changed the orbit of the previous prediction, making collision prediction more complicated.
"Starlink isn't announcing all of the satellite operations they're doing, but they've been making some minor corrections and tweaks. But that poses problems for others, as no one knows where the satellite will be or what it will do in the coming days. Lewis explained. He said there is currently no mechanism to share this information other than relying on experts to manually track releases, and with the increase in the number of Starlink satellites, this approach is simply not available.
Simk Hesser, CEO of Kayhan Space, a U.S. space transportation management company, confirmed the trend. The company estimates that, on average, operators managing about 50 satellites receive as many as 300 official collision alerts per week, including collisions with other satellites as well as debris. Up to 10 of those 300 alarms would require operators to perform "evasion operations," Hirser said.
Hesser expects this size to increase 10-fold in the near future, in part due to the growth of giant satellite networks like Starlink. "The problem is really out of control," he says, "and the current processes are all manual, not scalable, and if there is a collision, there may be (chain) implications because there is not enough information sharing between the parties." ”
Visualization of satellites and space debris around the Earth according to NASA
He likens the problem to "driving on a highway without knowing there was an accident ahead." If two spacecraft collide in orbit, the debris cloud generated by the collision will threaten other satellites passing through the same area.
Lack of regulation Musk accused of "making space rules"
Lewis also mentioned another issue worth worrying about. As the number of close-up incidents increases, so does the risk of operators making the wrong decision at some point. He noted that dodging requires fuel, time and effort, and that satellite operators assess costs and risks "carefully." However, the decision not to circumvent after receiving an alert can confuse the orbital environment for years or even decades.
This means that commercial satellite companies represented by SpaceX's "Starlink" plan may cause more serious security risks in the future.
Infographic. Musk is accused of making space rules.
For example, when the Starlink-44 satellite was close to the Fengshen satellite, the European Space Agency tried to contact SpaceX, but SpaceX did not take any countermeasures and did not want to disclose the reason. Afterwards, SpaceX claimed that a program failure of the company caused "no mail from the European Space Agency" to be received.
According to Jonathan McDowell, 26 of the Starlink moons that are still in orbit are completely out of control, but they are still operating in low-Earth orbit, waiting for them to slowly descend and fall back to the surface under the action of the thin high-altitude atmosphere.
European Space Agency Director Aschbach warned earlier this month that Musk was working on space rules because the "starchain" was so large that it would be difficult for regulators or competitors to catch up. "It's quite amazing that one person owns half of the world's active satellites."
According to foreign media reports, Aschbach's concerns were echoed by Luxembourg's economy minister, Fayote. Fayote believes that new rules are needed to ensure the safe use of space. He said at the country's space conference: "People like Musk, who launch satellites and also throw Tesla into orbit. We need to make common rules. Doing things in a completely deregulated space is a matter of concern. ”
Currently, there is no regulatory body in the world to control satellite launches. Chinese Foreign Ministry spokesman Zhao Lijian said at a news conference on the 28th that the 1967 Outer Space Treaty is recognized as the cornerstone of international law in the field of outer space. The Treaty stipulates that astronauts are envoys sent to outer space by all mankind, and that States shall respect and protect the safety of astronauts and notify the Secretary-General of the United Nations or other States parties of phenomena found in outer space that pose a danger to the lives or health of astronauts;
Zhao Lijian pointed out that the United States claims the concept of "responsible outer space behavior" in its own mouth, but it ignores the obligations of international treaties in outer space, posing a serious threat to the safety of astronauts' lives. He stressed that the US side should respect the international system of outer space based on international law, take immediate measures to prevent the recurrence of such incidents, and adopt a responsible attitude to safeguard the life safety of astronauts in orbit and the safe and stable operation of space facilities.
Red Star News reporter Xu Huan
Edited by Zhang Xun