Astronomer watches Starlink satellites sinking to build a ‘planetary barometer’

Dr. Tony Phillips, a renowned astronomer and author, has discovered a novel way to utilize SpaceX's Starlink satellite constellation as a planetary barometer. Phillips, who manages the spaceweather.com website, frequently monitors solar flares, solar wind, and geomagnetic shifts. In a recent article, he declared that Starlink has various drawbacks, including interference with astronomy, atmospheric pollution, and the threat of the Kessler Syndrome in Low Earth Orbit.

However, Phillips argues that Starlink serves another crucial purpose: acting as a reliable barometer for Earth's atmosphere. He explains that the Sun's ultraviolet radiation heats the thermosphere, causing the atmosphere to expand. When this happens, satellites lose altitude at an accelerated rate. To track this phenomenon, Phillips analyzes the Tracking and Launch Element (TLE) data for 1,000 Starlink satellites, along with 107 Planet Labs SuperDoves, 391 Amazon Kuiper satellites, and 651 Eutelsat OneWeb birds.

Each satellite constellation orbits at different altitudes, but Phillips has observed that they all move in response to the same solar events.

By examining the data, Phillips claims to have created a real-time, public index that demonstrates how the atmosphere expands and contracts in response to solar radiation. This novel approach eliminates the need for additional instruments, as the satellites themselves serve as the sensors. Phillips emphasizes that the data, derived from public tracking information, offers a valuable resource for understanding the Earth's atmosphere.