Discovered a New Binary Star? Nope, It's Just a Starlink Satellite

pcmag.com:

Astronomers have discovered evidence that orbiting Starlink satellites can contaminate their observations and appear as binary stars. 

Earlier this month, a group of astronomers published a preprint paper about “satellite contamination” of spectroscopic observations taken with LAMOST(Opens in a new window), a large telescope in China.

Unlike a traditional telescope, LAMOST can take a spectroscopy(Opens in a new window) of the night sky outside the visible light spectrum, enabling it to view the universe through other bands of electromagnetic radiation. The technique is particularly useful at identifying(Opens in a new window) binary stars, or solar systems with two suns.  

Past surveys of LAMOST data have revealed the presence of many “spectroscopic” binary star candidates, the paper(Opens in a new window) says. But further investigation has found that some of the binary stars appear to be “false positives” after looking at repeated observations. 

The astronomers then looked at the cause and suspect Starlink satellites launched in February 2022 may have been the culprit behind the false positives. As the satellites flew into orbit, they also began reflecting sunlight, which can be visible from Earth around twilight hours.

That said, the astronomers weren’t able to confirm the Starlink satellites crossed the telescope’s field of view, although the paper says exact positioning data on orbiting satellites can be “notoriously not very accurate.”

“Using the skyfield(Opens in a new window) package, the visibility of the (Starlink) satellite was verified, from LAMOST for the time of the observations,” the paper added. “Therefore, we suggest that the observations have been ‘photobombed’ by a train of Starlink satellites on