Imposter stars or quick flashes of light in the night sky has been attributed to the increasing clump of space debris and active satellites in Earth's orbit.
These bright flashes are often mistaken as stars, being recorded in astronomical studies, and are captured at an average of 1,000 times per hour, according to a report led by researchers from the University of North Carolina at Chapel Hill.
The new study, published in the Astrophysical Journal Letters Thursday, November 5, offers an explanation for the brighter-than-usual flashes that have captured the attention of amateur and professional stargazers.
Saving Future Studies From Misleading Twinkles
Most of these flashes are only visible under specific conditions - like the use of powerful viewing telescopes or within astronomical observatories - although there are about a hundred of them bright enough to be seen by the naked eye even from the suburbs.
"Astronomical surveys have seen occasional reflected light glints from satellites; those flashes can cause false alarms in surveys looking for new events in the sky," explains Hank Corbett, lead author of the study and a graduate student from the Department of Physics and Astronomy at UNC-Chapel Hill. He noted that their study is the first effort to focus on these night flashes "in a systematic way" to help reduce its impact on future astronomical discoveries.
Together with collaborators from San Diego State University and the University of Barcelona, the UNC-Chapel Hill team has documented more than 100,000 "imposter stars" over a six-month period. Researchers used Evryscopes, an array of gigapixel-scale telescopes situated in Cerro Tololo in Chile as well as in Mount Laguna in California. The rapid-cadence telescopes take observation of the sky above their observatories every two minutes. Corbett explains that the measurements they have collected allowed them to predict the effect of these reflected light instances on existing observational methods, which would guide future efforts to discount or mitigate its effects on future studies.
Suspicious Bright Lights
Orbital flashes are reflections of light from satellites that serve a variety of purposes - from communication, navigation, surveying, weather forecasting and more. However, the same flashes and reflections can also come from space debris - discarded rocket parts, decommissioned satellites, discarded panel linings from previous space missions.
These artificial flashes, from an Earth-based observer, might appear no different from actual stars. The same can be said about scientific observatories, capturing these lights that are visible for fractions of a second.
Corbett noted that "millions of stargazers" might have seen these imposter stars across the night sky, with these reflections happening quickly that some observers could just dismiss these phenomena as visual noise. Their systematic approach, however, offers an insight as to what causes these mysterious lights.
A press release from the University explains that these mysterious lights either appear as short flashes that mislead scientists into thinking that these are astrophysical events, or streaks of light made by very fast moving objects or slowly rotating satellites like members of SpaceX's Starlink constellation.
Peter Beck, CEO and founder of Rocket Lab, once said in a statement that the growing volume of satellites and debris in space is starting to post a threat to future space missions.
"Initial results show in theory, If you operated many thousands of satellites in LEO and were constantly and randomly moving them you could deny all launch to popular orbits as today's models and regulations would likely fail to converge conjunctions," Beck wrote in a tweet.
Check out more news and information on Space Debris in Science Times.