What is the effect of "dead" satellites falling to Earth?

A new study suggests that the burning of satellites as they fall to Earth may weaken their magnetic field.

In a worst-case scenario, this could strip our planet of part of its atmosphere, according to a new paper led by physicist Sierra Salter-Hunt, which warns of the risky implications of growing "mega-constellations" of satellites like those launched by SpaceX. For Elon Musk.

Salter-Hunt suggests that "spacecraft dust" from defunct satellites burning up in the atmosphere could create enough magnetic dust to cut our planet's protective shield in two.

The paper, which has not yet been peer-reviewed, reveals that the increased size of magnetic particles left behind by dead satellites could create a band of plasma dust with a stronger charge than the rest of the magnetosphere, the part of the Earth's atmosphere that protects us from sunlight radiation.

If giant satellite constellations develop as planned, the amount of dust they release could create a magnetic shield that could limit the Earth's magnetosphere's reach into space, protecting the atmosphere from solar radiation.

“I was shocked by everything I found, and no one has studied it,” said Salter-Hunt, a doctoral student at the University of Iceland. “I think it’s really worrying.”

In her research paper, she estimated that between 500,000 and one million private satellites could orbit our planet in the coming decades, with the primary goal of building huge constellations to provide the Internet, such as SpaceX's Starlink network, which can be monitored as it orbits the Earth.

Private satellites have already caused problems for astronomers, as they can interfere with radio telescopes and cosmic images, as well as posing a collision threat to other spacecraft.

But the biggest problem comes when the missions of these satellites end, as most of their structures burn up in the Earth’s atmosphere to reduce the amount of floating space waste, but this leads to an increase in the amount of evaporated metal particles.

Currently, it is unknown where all the spacecraft dust will eventually end up, but Salter-Hunt suggests that it may end up in the upper part of the ionosphere, a region of the atmosphere located between 50 and 400 miles above the surface.

Salter-Hunt fears that magnetic dust will cause problems, although scientists disagree.

But even if increasing radiation levels could destroy our atmosphere, Ms Salter-Hunt said this could take centuries, if not millennia, to happen.