Astronomers are increasingly concerned about light pollution in the night sky caused by the growing number of satellites, as well as space junk, in low Earth orbit.
Sunlight bouncing off satellite surfaces and junk negatively affects astronomers’ work because it interferes with their ability to get a clear view of the night sky. Light from satellites can appear as streaks in images from space, or it can be so bright that it prevents faint objects from being noticed.
In a series of papers published in Nature this week, astronomers highlight how the situation will deteriorate further unless regulations are implemented to reduce the number of launches that put small satellites into low Earth orbit.
Astronomers’ concerns about light pollution became more apparent when SpaceX began regular launches of several Starlink internet satellites from space in 2019.
SpaceX now has more than 3,000 Starlink satellites orbiting Earth, but could deploy up to 42,000 satellites in the coming years, according to a report by Digital Trend.
Amazon also has plans for a similar satellite internet service with Project Kuiper and more than 3,000 satellites are expected to be launched over the next decade.
Amazon also has plans for a similar satellite internet service with Project Kuiper and more than 3,000 satellites are expected to be launched over the next decade.
In response to astronomers’ concerns, SpaceX has tried to reduce the brightness of reflections on its satellites by adding masks to them. But in a paper from Nature, astronomers explain that this solution is not particularly effective because optically dark objects generally radiate brighter in the infrared and sub-millimeter wavelengths, causing interference with terrestrial observations at those wavelengths.
Astronomers are also concerned that deploying more satellites into low-Earth orbit increases the risk of collisions that will create more reflective space junk.
They said the problem could have “dire consequences” for terrestrial astronomy projects, with images sabotaging light and preventing astronomers from detecting fainter objects in the night sky.
“While it is a story of the democratization of space and the provision of affordable global broadband, it is a model that prioritizes urgency, privatized benefits, and short-term goals over true sustainability and the public interest,” said the authors of one of the articles. It also ignores our common ancestry and heritage in space.
Other newspapers commented: “The recently agreed UN High Seas Convention to protect international waters should give us hope that skies can be similarly protected. Events such as the recent appearance of the Northern Lights across the UK all the way south of England at the end of February remind people to look out.” His eyes are astonished. We must seize these sentiments and preserve these wonders for future generations.”
