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A shooting star during the Perseid meteor shower. Soon thousands of satellites will crowd the night sky. Image via Shutterstock / The conversation.
By Samantha Lawler, University of Regina
I walk out of my rural Saskatchewan home before dawn and look up, expecting to be breathless at the number of stars above me. I’m a professional astronomer, but I still enjoy naked eye stargazing as much as an impatient child. This is the first place I have lived that is dark enough to easily see the Milky Way and I am amazed and awestruck every time I look up.
This time, however, I swear softly. There is a bright satellite. And another sequel behind. And another. And another.
I was excited to see the artificial satellites, but now I know what’s coming. We are about to undergo a dramatic transition in our satellite experience. You will no longer run away from your city on a camping trip and see the stars unobstructed: you will have to look through a grid of bright, crawling satellites, regardless of your location.
Crowded orbits
If the mega constellations of satellites become reality, the night sky will become a mundane highway of moving lights, obscuring the stars. Now, every time I see the bright reflection of a satellite tracking through the stars, I am reminded of what has already been approved by the United States Federal Communications Commission, the agency that regulates the frequencies transmitted by satellites in the United States, putting itself in fact in charge of regulating every space launch on the planet.
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SpaceX has already received approval for 12,000 Starlink satellites and is seeking approval for another 30,000. Other companies are not far behind.
The Starlink mega constellation itself would increase the number of active satellites by more than tenfold: there are about 3,000 active satellites in orbit; Current Starlinks are 99% brighter because they are in lower orbits, closer to the Earth’s surface and more reflective than Starlink engineers predicted.
SpaceX is launching sets of 60 satellites every two weeks and there will be a thousand Starlinks in orbit by Christmas 2020.
Time-lapse photograph of the Lyrid meteor shower from April 2020. At 0:50 am, a train of Starlink satellites whizzes across the landscape.
With the naked eye, stargazing from a dark place in the sky allows you to see approximately 4,500 stars. From a typical suburban location, around 400 can be seen. Simulations show that from 52 degrees north (the latitude of both Saskatoon and London, UK) hundreds of Starlinks will be visible for a couple of hours after sunset and before. of dawn (comparable to the number of visible stars) and dozens of these will be visible all night during the summer months.
Light pollution has long been a threat to stargazing, but at least it can be avoided by leaving urban centers.
But satellites will be a global phenomenon that obscures the stars, especially severe in the latitudes of the northern United States, Canada and much of Europe.
Star sacrifices
To their credit, SpaceX and Amazon – which is also investing in satellite Internet services – have voluntarily begun to participate in discussions with professional astronomers about possible ways to mitigate the effects of thousands of bright satellites on specific observations, such as interstellar objects.
SpaceX also tried a “darksat” coating, although the astronomers’ preliminary measurements showed it was only marginally fainter than other Starlinks. Meanwhile, the launches continue with bright and absolute Starlinks.
Simulations show that professional astronomy and amateur astrophotography will be severely affected by the mega luminous constellations. The discoveries of dangerous near-Earth asteroids will be particularly devastated by the hundreds of Starlinks confusing their targets, leaving Earth more vulnerable to world-altering impacts.
The purpose of the Starlink mega constellation is to provide global Internet access. It is often claimed by Starlink supporters that this will provide Internet access to places around the globe not currently served by other communication technologies. But the information currently available shows that the cost of access will be too high in almost any place that needs internet access. Therefore, Starlink will likely provide an alternative only for residents of rich countries who already have other ways to access the internet.
Crowding the night sky
Even as SpaceX changes its plans, other companies are actively developing separate mega-constellations and there are more in the pipeline.
Currently, there are no rules on satellite orbits or right of way, and if a collision (or multiple collisions) were to occur, it is unclear who would be to blame and who should clean up the debris (if even possible). The only international law that applies to satellite debris, from 1972, basically states that the country that launched the satellite must clean up any mess it leaves on the surface of the Earth after the crash.
Space junk – or orbital debris – is a growing problem.
Most satellites today are launched by private companies, not governments, and most of the satellite debris remains abandoned in orbit because there are no rules on cleaning. There are thousands of pieces of this space junk, ranging in size from bolts to dead satellites the size of a bus.
With tens of thousands of new satellites approved for launch and no laws on orbit crowding, right of way or space cleanup, the stage is set for the disastrous possibility of Kessler’s syndrome, a cascade of debris that could destroy most satellites in orbit and prevent launches for decades.
Losing our connections
As humans, we have deep connections with stars that date back to the dawn of humanity and, in fact, we are made of material from ancient stars.
The Native Skywatchers program celebrates humanity’s ancient love of the night sky and shares indigenous knowledge of astronomy. An elderly Dakota recently shared her traditional knowledge of the skies: the spirit of the blue woman To Win lives in Wichakiyuhapi (the Big Dipper), where she leads new children from the star nation into our world and waits to greet our spirits at the door while we leave our world.
Big companies like SpaceX and Amazon will only respond to legislation – which is slow, especially for international legislation – and consumer pressure. Is having another source of the internet worth losing access to unhindered stargazing for you and almost every other person on the planet? Our species has been observing the stars for thousands of years, do we really want to lose access now for the profit of a few large corporations?
On your next clear night, go out and look up. Enjoy the stars you can see now, because without major changes in the plans of companies that want to launch mega constellations, your view of the stars is about to change dramatically.
Samantha Lawler, assistant professor of astronomy, Regina University
This article was republished by The conversation under a Creative Commons license. Read the original article.
Bottom line: How SpaceX Starlink satellites and other satellite mega-constellations will change the look of our night sky and our stargazing experience.
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