According to recent analyses, if unmanned spacecraft – such as those currently being launched in huge numbers – suddenly lose their ability to maneuver, as a result of a solar storm or a technical defect, experts will only have less than 72 hours to avoid a series of devastating collisions.

The number of orbital objects is increasing at a rapid pace, driven by the launch of huge constellations of satellites for communications and commercial purposes. Despite the great benefits that these networks provide, they contribute directly to the accumulation of space debris, raising the possibility of collisions, as well as polluting the radio and visible spectrum, and incompletely understood effects on the upper atmosphere resulting from the combustion of rocket remnants and satellite materials when they enter the atmosphere.

A report published by New Scientist magazine indicates that the number of active satellites in orbit has increased from about 4,000 in 2018 to nearly 14,000 today. The Starlink constellation, affiliated with SpaceX, is the main factor in this tremendous increase, as the number of its operating satellites currently amounts to than 9,000 satellites, orbiting at altitudes ranging between 340 and 550 kilometers above the Earth’s surface.

To assess the increased risk, researchers from Princeton University developed a new metric they call the “impact hour.” Their models revealed that if satellites in orbit in 2018 – before Starlink launched – had suddenly lost their ability to maneuver, it would have taken about 121 days for the first major collision to occur. Today, this deadline has decreased to only 2.8 days, which reflects the fragility of the current balance.

Professor Hugh Lewis from the University of Birmingham explains that this “clock” not only shows how crowded the orbit is, but poses an existential question: “Can we continue to build this fragile edifice? The moons there are, the severe the collapse will be at the first glitch.”

Despite these warnings, major companies – such as SpaceX and Amazon, in addition to Chinese companies – are planning to launch tens of thousands of additional satellites in the coming years, which reinforces experts’ fears that near orbital space may become unusable, closing a vital window to future scientific and commercial activities.

Source: science.mail.ru