The constellation of Starlink satellites already counts 775 active items , but SpaceX has already the approval to get to about 12 mila and then aims to launch others 30 mila, thus arriving at 42 thousand . Numbers that are scary and that will create a great crowding in orbit, which is already full of old satellites and space debris . SpaceX’s goal is “noble” (as well as economic), that is to cover the entire planet with ultra-broadband connectivity, even the most remote areas, but certainly not without dangers, such as the rate of satellite malfunctions which could lead to collisions .

According to an estimate, approximately 3% of Starlink satellites are no longer functional , over which there would be zero or little control. The satellites of the SpaceX constellation were designed to be maneuverable via an ion engine and even deorbit to burn in the atmosphere , but if the thrusters or communications do not work properly, the satellites could find themselves wandering in an uncontrolled way becoming a danger to other satellites and future human space missions, as already partially stated by the CEO of Rocket Lab last week.

Jonathan McDowell, astronomer at the Harvard-Smithsonian Center for Astrophysics, explained to Business Insider that he came to the estimate of 3% by analyzing the movement data satellites collected by SpaceX and the US government , showing which Starlink satellites have returned to Earth and which ones would not be under control. The 3% did not include the 45 satellites that SpaceX “pushed” intentionally out of initial orbit.

“I would say their failure rate is not striking , “McDowell told Business Insider. “It’s no worse than anybody else’s failure rates. The concern is that even a normal failure rate in such a large constellation will lead to a lot of space junk “. If SpaceX can indeed launch 42 thousand satellites as expected, a rate of 3% failure means something like “1260 satellites from 250 kg the size of a desk that goes aimlessly around the Planet “.

According to ESA data from last February, there were approximately 3200 satellites not functioning in the earth’s orbit , potential bullets ready to collide with other satellites creating a lot of space debris. In recent weeks, for example, there would have been a close transition defined as “very high risk” (a probability of 10% collision) between a dead satellite and the reject of a rocket body. Fortunately, that has not happened.

SpaceX claims that its satellites naturally deorbit or burn in Earth’s atmosphere if propulsion systems fail. However, this is a process that can take up to five years, according to the company. In filings filed with the Federal Communications Commission, SpaceX downplayed the risk, stating that it “considers unacceptable a bankruptcy of 10 or 5 percent of satellites to deorbit, and even a rate of 1 percent is unlikely. “

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Should 1% of the Starlink satellites lose any maneuverability, SpaceX still believes that there is “about 1% chance for decade for any failed SpaceX satellite to collide with one of the tracked debris. ” So much ado about nothing then? If you focus on SpaceX, perhaps yes, but if you think that Elon Musk’s company is not the only one working to bring tens of thousands of satellites into orbit, then the problem takes on very different connotations.

OneWeb plans to create a constellation consisting of 48 thousand satellites and Amazon wants to reach 3200 with its Kuiper fleet, just to name a few. In the case of satellites totally out of control, the collisions could create clouds of small debris that are very dangerous for future space launches.

Accidental tests and collisions that have already occurred, as well as 500 events in total, generated almost 130 millions of debris fragments in Earth’s orbit whizzing at more than 28 thousand kilometers per hour. If the space junk problem should