Analysis: Space debris descends faster with many sunspots
In times of particularly strong solar activity, decommissioned satellites have descended faster in recent decades. An analysis has shown this.
(Image: bombermoon / Shutterstock.com)
Space debris loses altitude significantly faster when there are particularly many sunspots on the sun and a threshold of about 67 to 75 percent of the sunspot maximum is exceeded. This is the conclusion of an analysis of the precise orbits of 17 space debris objects over a period of 36 years, which has now been presented. The research group from India responsible for this assumes that the EUV radiation, which is increasingly produced by the sun during these periods, is responsible for the faster descent through interactions with the Earth's atmosphere. Their findings are not only important for dealing with space debris but also for planning satellite missions and their fuel consumption.
Empfohlener redaktioneller Inhalt
Mit Ihrer Zustimmung wird hier eine externe Datenvisualisierung von Datawrapper GmbH geladen.
Ich bin damit einverstanden, dass mir externe Inhalte angezeigt werden. Damit können personenbezogene Daten an Datawrapper GmbH übermittelt werden. Mehr dazu in unserer Datenschutzerklärung.
The work is the first direct proof that objects in near-Earth orbit lose altitude measurably faster when the sun exceeds a certain level of activity, explains the research team. However, the process itself was known. When UV radiation and charged particles from the sun hit the Earth's atmosphere, it heats up and expands. In the case of satellites, this is the so-called thermosphere. For the objects orbiting the Earth, this results in a minimally higher resistance, which, however, slows them down measurably more, causing them to lose altitude. The evidence should now also help to better plan satellite orbits in the future to avoid collisions with space debris.
Rapidly growing number of satellites
Space debris is a growing problem for space travel. Debris and inactive satellites race around the Earth at immense speeds. Since even the smallest parts could destroy other satellites and create new space debris in the process, there is always the danger of a chain reaction. In the worst case, this could sweep entire orbits in Earth orbit clean, thus destroying the satellites there. Recently, such collisions with potentially catastrophic consequences have apparently been narrowly avoided several times. The issue has gained urgency because more and more mega-constellations are being planned and built, which consist of thousands of satellites, like Starlink.
Videos by heise
The work, now presented in the scientific journal Frontiers in Astronomy and Space Sciences presented on the connection between the descent rate of space debris and solar activity, is also based on data from Germany. The GFZ Helmholtz Centre for Geosciences monitors the number of sunspots and daily changes in the radiation of our home star, the research team writes. This information could be used. However, the group describes the fact that their work is based on satellite orbits launched in the 1960s as the most interesting. More than half a century later, they could still help research.
(mho)
