The huge communications satellite BlueWalker 3, which is particularly bright in the sky, can be significantly darkened by aligning the huge antennas. This is what three amateur astronomers suspect, who were looking for an explanation as to why the satellite became noticeably darker for several weeks in December. They justified their attempt at an explanation in a scientific article that was published on the preprint server Arxiv but was not checked. Most recently, the satellite was as bright in the sky as it was immediately after the giant antenna was fully opened.
Darkening of the sky possible
As the group around the not entirely unknown Scott Tilley explains, they assume that the huge satellite had to be realigned in Decemberto get enough sunlight. As a result, the dark back in particular pointed in the direction of earth, which is why the apparent brightness decreased noticeably. So far there has been no confirmation from the satellite operator. However, the three amateur astronomers see the process as proof that minor adjustments to the alignment can significantly reduce the brightness of such large satellites in the sky and the associated light pollution.
BlueWalker 3 is a test satellite from AST SpaceMobile that aims to prepare for the construction of the “first and only space-based broadband network for conventional smartphones”. In the future, at least 100 such giant satellites will orbit the earth and supply underserved areas with broadband internet. The satellites are designed to connect directly to traditional smartphones to provide a broadband connection to the Internet. On the other hand, its now unfolded antenna has an area of 64 m². It is the largest of any commercial communications satellite in low Earth orbit.
After unfolding the antenna, BlueWalker 3 had become one of the brightest objects in the night sky. Partly it reached an apparent magnitude of up to +1, only about 15 stars and five planets (as well as the moon) are brighter. In addition, the satellite acts as a kind of “mobile phone tower in space” and transmits strong radio waves on frequencies that were previously reserved for terrestrial communication. That’s why the International Astronomical Union has expressed concern that the satellite is a problem for both optical and radio astronomy. AST SpaceMobile says the internet project should fix one of the biggest problems. The amateur astronomers now believe that operators and the astronomy community could have a constructive dialogue based on the blackout.
(mho)
