It's a specific, unsettling feeling that comes when you look up at the night sky and see a train of bright lights speeding across the heavens.
When it happens, people often wonder if it's a sign of UFO activity — like one person last week who saw a video of the phenomenon in the west metro.
"Anyone else see the UFO a bit ago? Got this video sent to me from someone going west on Highway 212 between Eden Prairie and Chanhassen. He says it was a line of lights that disappeared," a post on X said.
The line of bright lights isn't a sign of life from some unknown planet; they are satellites from Starlink, the internet service from SpaceX.
"It's the craziest thing, if you didn't know what it was," said Peter Peterson, an associate professor in the Department of Computer Science at the University of Minnesota Duluth, who uses Starlink for home internet. "It looks like 60 stars in a conga line, basically moving really fast."
Satellite internet is nothing new. But older players in satellite internet use geostationary satellites, which are positioned about 22,000 miles over Earth and always orbit over the same patch of the planet, Peterson said.
Starlink satellites orbit about 342 miles above Earth, Peterson said. That means faster internet because the signal has to travel a fraction as far. But it also requires a lot more satellites, because there always needs to be one overhead to ensure service.
The first Starlink satellites launched in 2019. Since then, it's become fairly common to see them marching across the sky, and it likely will become more common as Starlink expands and as competitors potentially enter the market. Astronomer Jonathan McDowell,who tracks SpaceX launches, estimates more than 5,500 Starlink satellites have launched. Consulting firm Deloitte predicts as many as 50,000 satellites could be in low orbit by 2030.
What you're seeing when you spot a train of Starlink satellites in the sky is a recent launch, Peterson said. When the satellites are first launched from a rocket, they are close together and fairly bright. As they reach their intended orbit, they drift apart and appear to dim.
They don't dim completely, though, which is a concern for astronomers and others who are worried about dark skies.
"I can see them every night," said Bob King, an amateur astronomer and columnist in Duluth who goes by Astro Bob. "When you're looking at a galaxy, you want to see the spiral arms, and you want to see the details of nebula. And then here come a bunch of Starlinks, you know, like 'pew pew! laser coming through,' and they're very distracting."
SpaceX has been responsive to some concerns, King said. A coating has been added that makes the satellites dimmer and they now tilt, reflecting less light.
"The problem is that there are just so many of them," King said.
As people hope to see northern lights amid a peak solar storm cycle into next year, more may notice the launched satellites.
It's not just an issue for amateurs, but also professionals who can edit out aberrations in their photos caused by Starlink, but may lose important data in their analysis by doing so, King said.
On the aggregate level, so many satellites may cause light pollution in the sky that could affect an astronomer's ability to see.
Jessica Heim, a Central Minnesota resident, said she has been involved in many discussions with the International Astronomical Union about the effect of satellites on astronomy.
Heim, a PhD student in cultural astronomy at the University of Southern Queensland, said the sheer number of satellites also raises questions about people's relationship with the night sky.
Across human history, the night sky has played a huge role in everything from navigation to timekeeping to culture, Heim said.
These days, many people already live in places where they can't see the Milky Way because of ground-based light pollution sources — something that diminishes the human connection with the night sky, Heim said. You can generally escape light pollution in a remote place like the Boundary Waters or Antarctica, but you couldn't escape satellites.
"Even if you go out someplace that has a clear sky and you can see that … how do the satellites change that?" she said.
To learn when Starlink satellites are visible in your area, visit https://findstarlink.com/.