The shooting stars overshadowed by satellites

But is this bright point that spins in the night is really a shooting star. Nevertheless, a satellite that travels at a speed of 28,000 km/h, 300 kilometers above the surface of the earth?

This year. Moreover, more satellites will be launched than during the 50 years that followed Sputnikthe very first satellite put in orbit around the Earth in 1957, says Jean-Frédéric Morin, professor at Laval University and director of the Interdisciplinary Center for Research on World Governance.

In the near future. However, one in 15 bright points will be a satellite, according to Samantha Lawler, astrophysicist at the University of Régina.

“The stars will always be there. Therefore, but there will also be many other stars in motion in the sky, which are in fact satellites,” she says.

Ms. Similarly, shooting stars overshadowed satellites Lawler’s estimates show that there are about 12,000 satellites active in the sky, 8,000 of which are Elon Musk starlinks.

In 2020. Consequently, at the start of the Starlink constellation, there were 2666 active satellites, which represented 46% of the 5,774 objects in space. Therefore, In five years. However, the number of satellites in orbit could reach 100,000, believes René Doyon, astrophysicist at the University of Montreal and director of the Mont-Mégantic shooting stars overshadowed satellites Observatory.

“It may explode in a very significant way, and that is worrying,” he said Soleil.

The Far West – Shooting stars overshadowed satellites

The increase in satellites is exponential, notes Jean-Frédéric Morin. Consequently, And there is no sheriff to regulate everything. In addition, It is the Far West.

“In the past, only the great powers and a few multinationals could afford to have spatial activities. Consequently, Today, space is accessible to a wide range of actors, including developing countries, start-ups And universities, ”he says.

The emergence of SpaceX marked the boom of this industry. Moreover, We now favor constellations of thousands of small satellites in low orbit to reduce communication deadlines. In addition, improve coverage in distant communities in Quebec, for example.

“The international astronomical union cannot prevent progress and technologies. […] And either we cannot prevent cellular. internet coverage, “said shooting stars overshadowed satellites René Doyon, while stressing that the proliferation of satellites is” a problem “.

Professor Morin’s team at Laval University has set up the largest. database on international agreements framing space. There are about 2000.

“These are mainly bilateral agreements. and the majority of them are not legally binding,” certifies the professor specializing in global governance.

“We can dream of a multilateral treaty or a United Nations agency that would regulate satellite launches. However, in the current geopolitical context, it is an shooting stars overshadowed satellites illusion. What is currently prevailing is rather a race for low orbits, ”he adds.

“Domino” effect – Shooting stars overshadowed satellites

This frantic race is not about to end. It is motivated by both economic interests and national security considerations.

On the one hand. the constellations of satellites represent lucrative investments reserved for a few actors who will win the bet, as were railways or telecommunications networks, says Jean-Frédéric Morin.

On the other hand. independent internet access by satellite has become a strategic issue, pushing states like China or European countries to develop their own networks so as not to depend on the goodwill of the Elon Musk company, and thus find themselves in a position of vulnerability, as was the case for Ukraine, he continues.

However, proliferation poses serious risks.

“The more satellites we add, the higher the risk of collision. A collision generates debris, which can become very dangerous projectiles for other satellites. A bolt that travels thousands of kilometers on time can make big damage. ”

— René Doyon, astrophysicist at the University of Montreal and director of the Mont-Mégantic Observatory

There are currently 1.1 million debris of more than one centimeter around the earth.

“The effect [domino] occurs when these debris projected by the first collision collide in turn with other space objects. each collision projecting new debris and so on, generating an exponential series of collisions between objects, “explains Cynthia Duvet, which adds that the risk that this happens is particularly high.

Little risk of falling on someone

Due to its immense area, Canada is particularly vulnerable to the spinoffs of shooting stars overshadowed satellites space debris. Last summer, a Saskatchewan farmer discovered fragments of a SpaceX satellite on his farm.

“The risks that an individual is injured by the fall of a satellite are practically zero. but someone, somewhere on earth, will be killed in the future by an atmospheric back to school that could have been avoided,” certifies the astrophysicist Samantha Lawler.

A study published in 2022 in Nature Astronomy estimated at 10% the risk that a person dies. on the planet because of the fall of a satellite by 2032. This calculation did not take into account the tens of thousands of other satellites which should fall back into. the atmosphere during the same period.

“As the debris are more and more numerous and that some of them do not burn entirely in their fall through the atmosphere, this type of incident will become more and more frequent,” adds Jean-Frédéric Morin.

The International Telecommunications Union attributes orbits to satellites to avoid collisions and ensure radio communications with them. However, these trajectories are a limited resource, warns Ms. Duette.

“There may be saturation. especially considering the presence of outdated satellites and pieces of space objects emanating from past collisions,” she continues.

Latitude 50 to 54. which crosses certain regions of Canada, corresponds to shooting stars overshadowed satellites the area where the density of satellites in the sky is the highest, due to the privileged orbital trajectories.

“This band of latitudes is therefore also the most exposed to the risks of injury. damage caused by uncontrolled return,” warns Samantha Lawler.

Environmental consequences

Beyond direct risks for human life. atmospheric launches and revenues produce enormous amounts of pollution which are currently poorly measured, indicates to the Soleil The teacher in astrophysics at the University of Régina.

Having satellites from the sky also poses a high risk on the environment.

The destruction by combustion. which aims to disintegrate spatial objects by bringing them into the atmosphere, and the slowdown by combustion, which allows them to guide them towards a precise point of fall, generate atmospheric pollution, contribute to the depletion of the ozone layer and could disturb the climate shooting stars overshadowed satellites of the stratosphere.

Radioactive waste can fall back into the ocean and rockets emit black soot which absorbs heat and contributes to the acceleration of climate change, gives as an example Jean-Frédéric Morin.

“That said, it is important to emphasize that satellites are also precious tools for environmental protection.” The GPS system, for example, optimizes transport networks and reducing emissions, ”admits Mr. Morin.

Contamination

Satellites also hinder the work of astronomers. They alter approximately shooting stars overshadowed satellites 30% of the images taken by the terrestrial telescopes, including those of the all -new Vera C. Rubin observatory, the most powerful in the world, installed in the Chilean mountains.

“We can see the trail of the satellites, it’s very unpleasant. […] Within five years, all images could be contaminated, ”deplores René Doyon.

He suggests painting satellites in black to make them less visible. “We would no longer see them with the naked eye. The less they shine, the better it is, ”he explains.

This will not solve all the problems. The space. although it seems infinite from the earth, actually lacks space to accommodate all these satellites in orbit around our planet.

“Companies must find out how to provide their services with fewer satellites, but whose operational lifespan is longer. This is the technical challenge to be met for the shooting stars overshadowed satellites future, ”says Samantha Lawler.