If you haven’t had a chance to catch a glimpse of Comet NEOWISE, you might want to get out after sunset to check it out before this beautiful, radiant ice-ball fades away in the coming weeks. It will be your last chance to see it for 6,800 years, after all.
However, be forewarned that your view of the comet may be obscured by the bright reflective satellites that make up SpaceX’s emerging Starlink constellation. In fact, the satellites have been photobombing the comet in images taken by night sky photographers around the world.
SpaceX, along with companies such as OneWeb and Amazon, are launching these mega-constellations to provide broadband internet to communities around the world. Only a few hundred Starlink satellites have been launched so far, but ultimately these networks may contain thousands of individual spacecraft.
The deployment of abundant satellites in Earth orbit has provoked backlash from the worldwide astronomical community because of the light pollution that they introduce to the night sky.
“Satellite constellations such as Starlink are a major problem not only for professional astronomy but also for being an abusive appropriation of the night sky—a natural heritage of all humankind—preventing the observation of a pristine sky,” said Raul Lima, who studies light pollution at the Polytechnic Institute of Porto in Portugal, in an email.
SpaceX CEO Elon Musk has acknowledged this problem, and the company is responding by adding glare-resistant sunshades to the newer batches of satellites. Still, the older and brighter satellites will remain in orbit for at least a few years, so skywatchers can expect to be frequently “Starlinked,” a term that astrophotographer Stacey Downton, aka AstroStace, uses to describe the interference of the constellation with the night sky.
“[A]t the moment, with software and stacking images, we can ‘reject’ the Starlink trails from our final stacked image,” Downton said in an email. “But how long before we reach a point where we can no longer do that?”
Those hoping to capture long exposures of celestial sights are especially prone to getting Starlinked, according to Mark Brown, an astrophotographer based in Iowa.
“[W]ith the recent launch of the Starlink satellites and other big corporations wanting to do the same, are now facing a ‘sky pollution’ crisis with these hundreds of satellites,” Brown noted in an email.
“I understand that SpaceX is attempting to put into practice satellites that are shielded so as to not reflect as much sunlight,” he continued. “Regardless, in long-exposure imaging, the trails of the satellites will still be apparent. Can they be removed from images? Certainly, but that takes time and resources.”
John Crouch, an architectural and commercial photographer based in Chicago, learned this the hard way when he tried to capture NEOWISE on Wednesday evening, only to find trails of satellites in most of his photos.
“I don't shoot the night skies very often and last night was the first time in a few years,” Crouch said in an email. “I was somewhat shocked at how many satellite passes found their way into the photos. I was out there shooting for about six hours and I'd say about half to 2/3rds had Starlink satellites in the shots.”
“It basically takes three hours to go from Chicago to a dark sky (and three hours back),” he continued. “I'm sure you can imagine my fatigue-fueled annoyance at those satellites for crashing my photos! And that's part of the problem. Light pollution is everywhere humans reside. The irony is Musk's plan to provide service to underserved areas harms one of the few unique advantages of living in a remote setting.”
Julien H. Girard, a physicist and support scientist at the Space Telescope Science Institute in Baltimore, also pointed out that these mega-constellations are particularly damaging to dark rural skies.
“For the general public, at any given time after dusk and before dawn, there will be more visible sats in the sky, especially from rural areas, probably tens of them,” he said in an email.
“As a tech lover to some extent, I see why people find that ‘cool’,” Girard added. “I also enjoy watching the SpaceX rockets landing back to Earth to be reused. But shouldn’t there be more regulations? More scientific and ethical assessment to what is OK and what isn’t? Long term planning?”
To that point, Girard cited several recent efforts to anticipate the effects of escalating satellite light pollution on astronomy from major organizations such as the European Southern Observatory and the American Astronomical Society.
Lima also emphasized that international regulation of the constellations is “urgent” in order to preserve a clear view of the night sky, especially when rare and beautiful visitors such as NEOWISE show up.
“Due to the rising levels of light pollution worldwide, when these short-term phenomena happen such as the visit of a comet, to see it conveniently we are today left with no option than to drive dozens or hundreds of kilometers to find a place with less light pollution,” Lima said.
“This is a permanent problem for those lucky enough to live under pristine skies, i.e., with no light pollution,” he continued. “For those of us who are for now condemned to live under strong light-polluted skies (the majority of the population), not even under dark skies will those citizens have the opportunity to contemplate a starry night without strong artificial interference.”
Jaime Cordova, an astrophotographer based in Wisconsin, pointed out that “a rare astronomical event” such as the appearance of comet NEOWISE means that “every shot counts.”
“I see a lot of arguments being made that ‘it's time for astronomers to give up a monopoly on the sky’ and that this will push for more space-based telescopes, but that's simply not the case,” Cordova said in an email. “It's challenging to put telescopes into space.”
“Aside from that, the night sky is a beautiful thing to look at (and wonder about),” he concluded. “I want to see real constellations, not satellite constellations.”
SpaceX did not respond to a request for comment.