A total of 49 satellites took off last Thursday from Florida aboard a Falcon 9 rocket. They were to be part of the Starlink constellation, intended to provide internet from space.

But the deployment of this new batch was “significantly affected by a geomagnetic storm on Friday,” SpaceX wrote in a blog post published Tuesday.

These events are due to eruptions on the surface of the Sun, which can cause particles to be ejected all the way to Earth, where they cause a magnetic storm.

These storms are notably the cause of the aurora borealis, but can also disrupt telecommunications.

"These storms warm the atmosphere and increase atmospheric density at our lower deployment altitudes," SpaceX said, noting that the satellites had been placed in an orbit approaching Earth at an altitude of 210 km at the closest.

There, SpaceX carries out checks, before sending its machines higher.

This way, if they don't work, they can be easily redirected back to Earth and thus not create space junk.

To counter the resistance effect induced by the magnetic storm, the satellites had been placed in "secure mode", the company explained.

But "preliminary analyzes show that resistance at low altitudes prevented the satellites from leaving safe mode to begin their orbit elevation maneuvers," she continued.

Result: "up to 40 of the satellites will re-enter or have already re-entered the Earth's atmosphere."

They pose no risk of collision with other satellites, SpaceX reassured, and are designed to disintegrate in the atmosphere, so that “no part of the satellite touches the ground”.

Starlink's first satellites were sent in May 2019. The constellation currently includes around 1,500 active satellites, Elon Musk tweeted in mid-January, and the company plans to position thousands more.

© 2022 AFP