SpaceX’s artificial constellation of broadband-providing satellites could increasingly spoil views of the night sky and hinder astronomy, experts say.
Elon Musk’s Starlink project recently placed 60 satellites in low-Earth orbit as they look to beam high-speed internet down to the the planet’s surface.
It soon became clear that the bright train of orbiting satellites were quite visible to the naked eye, as astronomers and space enthusiasts tracked the launch.
The sight has provoked an outcry among the astronomy community, with the development seen as a new headache for researchers who already have to find workarounds to deal with objects cluttering their images of deep space.
SpaceX’s plans for the Starlink program are fuelling concerns, with the firm setting its sights on increasing their artificial constellation to 12,000 satellites by 2025.
University of Alabama astronomer Bill Keel told the AFP that the sighting of the satellite train had experts trying to extrapolate what effect artificial constellations of such steady brightness might have as they grow in size and number.
Fears developed, he said, that ‘in 20 years or less, for a good part the night anywhere in the world, the human eye would see more satellites than stars.’
The brightness of the satellites has since dimmed as they ascended to their final orbiting altitude of around 340 miles (550 kilometres) above the Earth’s surface and stabilised their orientations.
However, this has not entirely allayed the scientific community’s concerns, with fears as to how views of the night sky will be impacted with SpaceX’s plans to increase the number of orbiting satellites from 60 to 12,000 over the next five years.
There are currently 2,100 active satellites orbiting our planet, according to the Satellite Industry Association — and SpaceX is not the only company looking to enter the burgeoning space internet market.
Yet even if SpaceX alone adds another 12,000 satellites, there ‘will be hundreds above the horizon at any given time,’ Harvard Smithsonian Center for Astrophysics researcher Jonathan McDowell told the AFP.
This issue will be exacerbated at specific times of the year and during certain points in the nighttime, he noted.
‘It’ll certainly be dramatic in the night sky if you’re far away from the city and you have a nice, dark area.’
‘It’ll definitely cause problems for some kinds of professional astronomical observation.’
SpaceX CEO Elon Musk offered contradictory messages on Twitter in response to the concern.
Despite reporting he had already taken steps to investigate ways to reduce the reflectivity of the Starlink satellites, Mr Musk also said that ‘Starlink won’t be seen by anyone unless looking very carefully’.
The satellite constellation ‘will have ~0% impact on advancements in astronomy’ and we ‘need to move telescopes to orbit anyway,’ he added.
While SpaceX cares ‘a great deal about science’, the work to give ‘billions of economically disadvantaged people’ high-speed internet access through the Starlink network ‘is the greater good,’ he wrote.
Responding to Mr Musk’s comments, Professor Keel said that he was happy that the SpaceX CEO had offered to look into ways to reduce the reflectivity of future satellites, but questioned why the issue had not been addressed before.
If optical astronomers are concerned, then their radio astronomy colleagues are ‘in near despair,’ Professor Keel added.
Radio astronomers rely on the electromagnetic waves emitted by celestial objects to examine cosmic phenomena — such as the black hole that was imaged last month.
So-called ‘side emissions’ generated by satellite operators can interfere with the observation bands that radio astronomers are looking out for if not adequately mitigated.
‘There’s every reason to join our radio astronomy colleagues in calling for a “before” response,’ said Professor Keel.
‘It’s not just safeguarding our professional interests but, as far as possible, protecting the night sky for humanity.’
Amateur astronomer Marco Langbroek caught footage of dozens of miniature satellites from SpaceX’s Starlink project traversing their new orbit around Earth.
In the video, shot from the Netherlands, the satellites — which appear as a string of consecutive lights — can be seen flying through the night sky a little more than a day after they were launched.
A blog post from Langbroek detailed the amateur astronomer’s excitement as the satellites entered his camera’s field of view.
‘It started with two faint, flashing objects moving into the field of view,’ he wrote.
‘Then, a few tens of seconds later, my jaw dropped as the “train” entered the field of view. I could not help shouting “OAAAAAH!!!!” (followed by a few expletives…).’
To time the satellites voyage and get the video, Langbroek said he calculated the instruments’ orbit himself.
‘There were no orbital elements for the objects available yet on Space-Track, but based on the orbital information (53 degree inclination, initially 440 km orbital altitude) I had calculated a search orbit and stood ready with my camera,’ he wrote in a post.
‘My search orbit turned out to be not too bad: very close in sky track, and with the objects passing some 3 minutes early on the predictions. And what a SPECTACULAR view it was!’
While Langbroek set up his camera in anticipation of viewing the satellites, other stargazers weren’t anticipating the spectacle, causing an outpouring of UFO claims.
Following the fly-by dutch UFO website www.ufomeldpunt.nl was flooded with reports.
‘There’s a long line of lights. Faster than a plane. Huh?’ said one poster.
‘Bizarre train of stars or lights moving across the skies at constant speed,’ posted another.
In a report by dutch outlet, NOS, one witness said he was concerned the lights were an attack.
‘I didn’t know what to think,’ said an eye-witness who saw the lights go over The Hague reports NOS. ‘Is Russia attacking America? Are they UFOs? I really didn’t know.’