Satellite trails, May 19, 2021. | SkyNews
Satellite trails, May 19, 2021. (Dr. Phil Langill, Director RAO, UCalgary)

More satellites, more problems

The number of active satellites in orbit (as of November 4, 2022 at 16:05:27 UTC) is 6,843 — 3,273 of which are Starlink units, up from 1,655 on September 1, 2021.

An increasing number of satellites are being deployed into low Earth orbit (LEO), impacting the way some scientists conduct their research.

Dr. Phil Langill, director of the University of Calgary’s Rothney Astrophysical Observatory, is one such example. He sees these communication satellites, which include SpaceX’s Starlink, as creating a “whole new concern” to the research astronomer.

“There’s all sorts of things we’re discovering now that are just sudden little flashes of light. So when I’m combing through all that data, I’m looking for little flashes of light, because those are the really interesting things,” said Langill in an interview with SkyNews.

Langill uses equipment similar to what many RASC astrophotographers use, but in a slightly different way and for a different purpose. His focus is on the pixels of the images he captures; those images contain data that he uses to analyze, make measurements, and ultimately make conclusions about how the Universe works.

But what if a flash of light he captures is a satellite?

“What if I spot one and I start making some interesting conclusions about some interesting phenomenon of physics in the far reaches of the Universe?” 

Satellite trails, May 19, 2021. | SkyNews

“The more man-made things we put in the way of trying to capture the natural light that comes to us from [the] Universe, [the more it] makes the research [increasingly] difficult all the time.”

The issue, Langill noted, is the potential to make a mistake. The fact that a flash of light could be a blink of light off a satellite passing overhead is concerning. The increasing number of satellites in LEO also creates more background light that researchers need to filter through to find their real measurements. 

“The more satellites that go up, the more likely it is that your detailed, tiny little observation of some faint flash from across the Universe is actually just some man-made thing that’s floating around in the orbit above the Earth,” said Langill. “It’s a big problem, and it’s going to get worse and worse and worse.”

Some satellite providers may keep track of these orbits and share the information online, which would allow astronomers to understand when the satellites will enter their vicinity. But Langill said orbits degrade as predictions start to wander from where the satellites really go. After a few months, it becomes hit-and-miss, which brings into question the reliability of the information.

“Was there a satellite overhead that night? You’re still 50-50 on if you were right or wrong, based on the website. So yes, it’s hard [and] it’s getting harder,” said Langill. 

He also tweeted one of his photos with satellite streaks and received comments from users about asking why he did not edit the image. Langill said such comments speak to the fact that many people do not understand what astronomers do.

“The goal that I had after that night was not to take a pretty picture of satellites or clusters. This is scientific data, and I’m using the data to try and make discoveries about the Universe,” said Langill. “If I photoshopped out the streaks, I would be fudging my data, which you cannot do in science.”

He said the goal is not to create beautiful pictures — it’s about science. And the telescopes and detectors being used provide top-notch data, which comes in the form of counting photons. 

“The more man-made things we put in the way of trying to capture the natural light that comes to us from [the] Universe, [the more it] makes the research [increasingly] difficult all the time.”

Catch-22 and satellite pollution

The impact of communication satellites on data is not news for the scientific community. But for people like Dr. Samantha Lawler, a professor of astronomy at the University of Regina in Saskatchewan who is well aware of the catch-22 situation unfolding before her, it is problematic. 

“Their purpose is to make [high-speed] internet access easier for [people living in] rural or remote locations that don’t have other options,” said Lawler. “I realize this is totally useful, but [it’s] the way that the satellites have been deployed — they’re very reflective, and there’s a lot of them. So it’s really easy to see them in dark night skies.”

Starlink is a new constellation of satellites that SpaceX is in the process of launching, but SpaceX is not the only provider of satellites in LEO. Others include OneWeb, Amazon’s Project Kuiper, and AST SpaceMobile’s BlueWalker 3. The difference, according to Lawler, is that SpaceX now owns the most satellites of any entity in the world.

According to non-profit organization CelesTrak, the number of active satellites in orbit (as of November 4, 2022 at 16:05:27 UTC) is 6,843 — 3,273 of which are Starlink units, up from 1,655 on September 1, 2021 (based on Dewesoft data). In comparison, OneWeb has 461 units, up from 288 during the same period, and based on the same sources. 

“There are several companies that have plans for tens of thousands of satellites,” said Lawler, adding that SpaceX has plans to increase its units over the next few years.

Lawler, along with Aaron Boley and Hanno Rein, published a peer-reviewed paper in the Astronomical Journal in 2022 that provided predictions for the “optical brightnesses and on-sky distributions” of 65,000 satellites on their filed or predicted orbits. This includes Starlink, OneWeb, Kuiper, StarNet, and Guo Wang (also known as GW).

Simulation of the night sky with 65,000 satellites. | SkyNews
This image shows a simulation of the night sky with 65,000 satellites. Each dot is a sunlit satellite that is visible from latitude 50N on the Summer Solstice at midnight. The colours show brightness; everything that is pink, orange, or yellow is bright enough to be visible to the naked eye. The number of sunlit satellites is given by N or Ntot, and the number of naked-eye visible satellites is given by Nvis. (Lawler, Boley, & Rein (2022), The Astronomical Journal vol. 163, issue 1)

Their visibility predictions for near-future satellite megaconstellations (thousands to tens of thousands of artificial satellites in LEO) is that latitudes near 50-degrees north and south will be the most impacted by light pollution. 

“Our prediction was that latitude 50 degrees is actually the worst place in the world for light pollution from these satellites — right in Canadian territory, [and] right where I live,” said Lawler. “At the worst, in the summertime from my latitude, from my house, there will be a couple of hundred naked-eye visible satellites all night long, all flying around the zenith.”

Based on her research, one in every 14 stars in the sky will be a satellite.

SkyNews reached out to both Starlink and SpaceX for a comment, but did not receive responses.

Next steps

In July 2022, SpaceX published a report on its website, noting that it has taken “unprecedented steps” to work with the astronomy community to better understand how the company and its satellite operators “can mitigate the effect that the Sun’s reflection off of satellites can have on astronomical observations.”

But Lawler said that without government regulation, there may not be a strong incentive to meet a particular level of brightness. And since the units are operational for only a few years, what happens when they burn up in large numbers in the atmosphere? 

“What is that going to do to the atmosphere? There’s no environmental regulation at all. There are a whole bunch of issues with pollution and space junk that are worldwide, and that affects Canada just as much as everybody else in the world,” said Lawler.

She, like other astronomers in the field, believes governments need to regulate LEO providers to ensure there is an incentive to manage safety issues, light pollution, and “space junk,” while still offering internet connectivity to remote locations.