An avalanche-like increase in debris in orbit threatens to deprive all earthlings of space

The low-Earth Debris cascade of debris that will destroy the Hubble Space Telescope and the International Space Station was vividly portrayed in the film Gravity starring Sandra Bullock, and it came to mind by the explosion of its own satellite, carried out by the Russian military early on. Monday, November 15th. Representatives of many space organizations in the world expressed indignation over these experiments and reminded that the surrounding outer space is a common resource and space wars are unacceptable. How real and inevitable is the negative development of events?

Plans to conduct such experiments were not announced in advance, and after space divisions in various countries expressed their indignation, Roscosmos’ partners assured that the danger had passed: “At the moment, the crew of the International Space Station performs regular work according to the flight program. other issues are not within the jurisdiction of the state-owned company Roscosmos. statedthat Russia destroyed the inactive Tselina-D satellite in orbit as part of activities “to ensure defense capabilities aimed at preventing sudden damage to the country’s security in space and on Earth by existing and promising space assets from other states.”

The destroyed satellite was launched in 1982 and has not worked for several decades. The type of weapon that shot him down is not known for sure. Defense Minister Sergei Shoigu said a “promising system” was used, which “brilliantly hit the old satellite”.

As a result, a cloud of space debris formed in orbit. Russian Foreign Minister Sergei Lavrov, in response to the allegations, recalled that the Pentagon itself tested such orbital weapons. It is also known that in January 2007, China used its version of anti-satellite weapons, which at the time also aroused indignation in the United States and other countries. A ballistic missile was launched from the Xichang Chinese Space Center in Sichuan Province, which at an altitude of 865 km destroyed the old meteorological satellite Feng Yun 1C, which was launched into orbit in 1999.

After the Russian military destroyed their inoperative satellite, the ISS crew was forced to take refuge in the descent vehicles, as debris flying at high speed dangerously close to the ISS could jeopardize the station’s airtightness. In some cases, satellites and spacecraft can still maneuver away from space debris that particularly threatens them, but perhaps sooner or later the situation will turn out to be such that the number of debris in orbit begins to grow like a snowball, and an increasing number of orbital collisions will actually cut off humanity from space. This scenario itself, in the initial stages that we may already be, has been called Kessler’s syndrome.

Donald Kessler, then at NASA, addressed this scenario in his prominent 1978 newspaper with the title “Collision frequency for artificial satellites: creation of a junk belt”.

He warned that as “the number of artificial satellites in Earth’s orbit increases, so does the likelihood of collisions between them.” “A collision between satellites will lead to the formation of additional fragments in orbit, each of which increases the likelihood of further collisions, gradually leading to the growth of a cloud of debris around the earth,” Kessler believed. As this cloud becomes denser with time, Kessler expressed concern that it will be “a major problem in the next century”. Kessler has not been with NASA since 1996, but he is still an active member of the space debris community to this day.

The phrase “Kessler Syndrome” was coined by John Gabbard, who tracked satellite destruction events for NORAD – North American Aerospace Defense Command, North American Aerospace Defense Command – a joint US-Canadian air defense system that provides control over air and near space and warning of airstrikes against these countries .

Kessler later developed the meaning of the term, stating that it “is intended to describe the phenomenon where random collisions between objects large enough to be cataloged pose a danger to spacecraft due to a cloud of small debris, the number of which begins to significantly exceed the number of meteoroids. of natural origin. He added that “this phenomenon will eventually become the most important long-term source of garbage” if we do nothing about it.

This “stand-alone, erratic, cascading collision process” is likely to be greatly accelerated by the frequent use of anti-satellite weapons. So far, only one case is known when one of the non-functioning satellites spontaneously crashed into another and worked, and this happened on February 10, 2009. On that day, the American communications satellite Iridium 33, which is part of the satellite constellation of the same name and launched into space from Baikonur by the launch vehicle Proton-K, with the already dead satellite Kosmos-2251.

According to some estimates, there are currently around 330 million debris in the space around us, which seems to be an incredible number. Apparently no one has sent out 330 million individual objects in orbit, but the problem is that debris in space can multiply, break up into many smaller and smaller particles, which can then crash into other objects and so on. As a result of all this, the number of debris increases exponentially over time.

Large areas in low orbit around the earth, especially the highly coveted band between 900 and 1400 km, will eventually become inaccessible for long periods of time measured in decades.

In 1991, Kessler stated that “it is now necessary to begin limiting the number of missile bodies and other objects left in orbit.” Decades later, this warning, which at the time seemed overly pessimistic, began to take on very real and even threatening features, given the pace of launching more and more new rockets into space. In addition, attempts to disrupt this process may already be unsuccessful, as the rate at which space debris is created is now higher than the rate at which this debris falls and burns into the Earth’s atmosphere.

“Simulation results confirmed by test data [ВВС США]as well as a number of independent researchers, suggest that the current space debris situation is unstable or exceeds a critical threshold, so that any attempt to reduce the number of debris by eliminating their sources is likely to fail: new collision fragments will be generated faster than the previous deorbit retardation in the upper atmosphere “, wrote Kessler in 2009.

The European Space Agency agrees that the debris generated from the collisions will begin to dominate the useful parts of the low-Earth orbit, and this will be a factor that must be constantly considered, “even if all launches are stopped completely, which is extremely unlikely. . ” In addition, the geostationary orbit, which extends over the earth in the area of ​​36 thousand km and which hosts hundreds of satellites, is also not immune to the “Kessler syndrome”.

However, Kessler never claimed that a destructive cascade of debris could form within a short period of time, estimated at several days or months, or that this cascade could be triggered by a single space launch. The film Gravity from 2013 used just such a scenario, where the destruction of a Russian satellite led to cascading events, the rapid proliferation of space debris that eventually destroyed the International Space Station. In reality, a single triggering event is unlikely to lead to massive destruction of satellites, but collisions that create large amounts of debris can significantly speed up the entire process.

There is a tendency to constantly incite “Kessler’s syndrome”. Space launches are becoming cheaper, space is becoming more and more accessible for commercial exploitation. Miniaturization allows you to create smaller and smaller satellites and again reduce the cost of their operation. This means that with each launch, an increasing number of satellites are launched into space. In addition, there is a trend towards satellite mega-constellations, where entire fleets of orbiting spacecraft work together to provide services such as broadband Internet connection. Elon Musk’s SpaceX, which has already launched more than 1,700 Starlink satellites into orbit, is considered a leader in this direction, but other companies, such as OneWeb and Amazon, which intend to distribute similar space constellations, are also catching up.

There are currently about 7,630 satellites in Earth’s orbit, of which about 4,700 are still in operation (ESA estimates). Each object placed in orbit increases the risk of collisions, and each collision in turn increases the probability of future collisions. This can make the prospects for the long-term viability of satellites quite dubious.

When will an unacceptably high density of debris make the Earth’s orbit a place unsuitable for satellites, space stations and astronauts, and how long can this last? In the worst case, the existing debris cloud will destroy several more satellites and make parts of the Earth’s orbit unusable for any long-term operation. The debris cloud below 500 km will eventually fall back to earth, but this will take a decade or more. In the case of the area over 600 km, it can remain closed indefinitely if we do not find a way to forcibly clear it.

All this entails significant risks for modern telecommunications systems, the absence of the already known services of global positioning systems GPS, financial systems will also suffer, the military potential in many countries will be largely lost, and among other things, the world will lose weather satellites and mapping tool. That is to say, humanity will largely return technically to the middle of the 20th century.

But there are still ways to reduce space debris. These include limiting the amount of new space debris through systematic decontamination operations, such as maintaining and repairing satellites in orbit; avoid collisions in space, for example by ensuring the maneuverability of all satellites and banning anti-satellite weapons tests; make more impact-resistant satellite cases; and finally, some problems can be solved by a more responsible approach to disposing of satellites that take out their resources – for example, by developing satellites that can turn independently. It is also very important to look for new and effective ways to remove existing space debris.

It is likely that over time, reasonable limits will also be adopted for the amount and type of objects that will be allowed to be sent into space. It will not be easy to agree on this with all parties, including various states and private traders, but this forced action will help maintain a healthy ecology in close proximity to Earth and avoid the loss of this resource.

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