What is space debris and where did it come from

American astronomers said that accumulations of space debris in Earth orbit – decommissioned satellites, other artificial objects and their debris – began to make it difficult to observe space. Millions of pieces of such debris are increasingly affecting the operation of highly sensitive ground-based telescopes, causing growing concern among scientists. In some countries, there are already programs to clean up the orbit, and astronomers are now proposing to make sure that satellites do not interfere, but rather help science.

Lasers are not for icicles

“This is a very hot topic,” he said in an interview. The New York Times Louisiana State University astronomer Eric Burns. “We have to deal with so many satellites that they simply limit the capabilities of highly sensitive ground-based telescopes.”

To date, the amount of space debris in Earth orbit – defective or end-of-life satellites, their fragments, components or fragments of rocket stages, upper stages and other artificial bodies – has reached astronomical proportions. According to official data from the European Space Agency (ESA), in orbit located more than 131 million pieces of space debris.

Since 1957, when the USSR launched the first artificial Earth satellite, more than 6,500 rocket launches have taken place all over the world. More than 15,000 satellites have been put into orbit.

If for some reason such a satellite was not disposed of after the end of its service life or simply turned out to be abandoned, it continues to be in orbit, it may collide with another satellite, as a result of which, instead of two pieces of space debris, there is a risk of forming several tens or hundreds.

In recent years, some countries have launched programs aimed at cleaning up the Earth’s orbit. Last December, the US Senate approved law The Orbital Sustainability Act (ORBITS Act), which mandates NASA to develop a detailed plan for orbit cleanup. To do this, NASA and other US agencies, as well as attracted private companies, will first create a list of artificial space objects that “pose an immediate safety threat to operating satellites, as well as to other orbital activities.” Then the specialists will present a plan for the disposal of these objects.

Methods may vary. In March, NASA published a special report. According to agency experts, cleaning up only the 50 most dangerous large pieces of debris in the first year alone will reduce potential risks for operating satellites by $3.5 million. Cleaning smaller items – about 100,000 – will reduce risks by $23 million in the first year.

“To clean up large pieces of debris, we analyzed five possible scenarios,” notes NASA. “Trash capture with subsequent controlled release into the ocean; capture of garbage with subsequent uncontrolled entry into the dense layers of the atmosphere with subsequent combustion of garbage; destruction or movement of debris from a dangerous trajectory using a laser; moving debris from a dangerous trajectory using a special high-altitude probe; disposal of debris in orbit by dispersing or burning it.

To clean up small objects, NASA is considering the following options: using ground or orbital laser systems to destroy them, as well as using a special apparatus to collect or disperse them.

The agency has already calculated the cost for various types of space debris cleanup – from $500 for a single use of a laser to destroy a small piece of debris in low Earth orbit and up to $60,000 for the controlled descent of a large piece of debris into the ocean, followed by search and disposal.

NASA does not say which methods it considers the most promising. The Office notes that now the government, Congress and experts must analyze this report, give their assessments, determine the budget and action plan for the coming years.

SSR will come – put things in order

Back in 2016, the World Economic Forum began developing a program Space Sustainability Rating (SSR). aim of this program is to encourage more responsible use of Earth orbit for research or commercial purposes. To the project joined The European Space Agency, and six years later – in June 2022 – the launch of the program was officially announced.

Its essence lies in the fact that all organizations or companies that want to launch their satellite or other apparatus into orbit apply to SSR with a description of their plans, including the disposal of spent units or their launch on safe trajectories. SSR experts study this plan, give it their opinion and, if necessary, help the company or organization to finalize the satellite operation plan so that it does not turn into dangerous space debris: calculate the dangers of collision with other objects in orbit, dispose of it by descending into the dense layers of the atmosphere, or remove to a safer trajectory in orbit.

SSR also provides expert advice to companies and organizations that are ready to launch vehicles to clean up or dispose of already existing space debris.

The creators of SSR note that a positive assessment of a project is beneficial for the companies themselves, which can thus attract new investors or receive a positive public response for their business.

Currently, the SSR project, in addition to ESA, includes a special working group Space Enabled from the Massachusetts Institute of Technology (MIT), the University of Texas (Austin), Nihon University (Tokyo, Japan), the American engineering and research and consulting company BryceTech, the French telecommunications company Stellar Telecommunications. The European Space Agency says that SSR has great potential in the near future.

“Many large companies such as Airbus, Lockheed Martin, SpaceX and Voyager Space Holdings have actively supported the concept of the program and have expressed interest in participating in it,”— notes ESA.

Astronomers also offer to work for the future. Eric Burns of Louisiana State University and some of his colleagues are proposing miniature sensors to measure cosmic gamma rays on new satellites. In August last year, an international team of scientists prepared, with the support of ESA, reportin which he proposed to equip new satellites of the European geopositioning system Galileo G2 with sensors.

According to scientists, this will not only help the study of space, but also save money on launching separate research satellites and probes to measure gamma radiation. Scientists hope that commercial satellites equipped with such sensors, even after completing their direct commercial task, will not interfere, but will help ground-based observatories in collecting information about bursts of gamma radiation in the solar system, about deep space, solar radiation, etc. If the number of such satellites will be large enough, they can even form something like an orbiting gamma-ray telescope.

“There are a lot of questions that we can get answers to in this way,” Mr. Burns believes. current ones.”

Scientists already have successful experience of cooperation with commercial satellite operators. Since 2011, the American telecommunications company, satellite operator Iridium, has been installing magnetometers on its satellites as part of a special joint project with the Applied Physics Laboratory of Johns Hopkins University (Baltimore, USA). During this project, called Ampere (Active Magnetosphere and Planetary Electrodynamics Response Experiment) scientists explore the Earth’s magnetosphere and ionosphere. Including are watching for geomagnetic radiation, disturbances in the ionosphere, and also receive real-time data on how the ionosphere and magnetosphere protect the Earth from the solar wind – a stream of charged / ionized particles flowing from the solar corona.

Evgeniy Khvostik