Starry nights: one point of light out of 15 will soon be a satellite!

I’m outside on my farm in Saskatchewan chatting with my neighbors who I’ve invited over to look at the sky nocturnal with my telescope. After the exclamations and the wonder at the rings of saturn and the light that has traveled through space for more than two million years since the andromeda galaxy to reach our gaze, our conversation inevitably deviates towards the pandemic, our teleworking organization and complaints about Internet in rural area. My neighbor mentions in passing that he has just changed supplier for star link.

I look up and notice a bright satellite moving across the sky. It is most likely a star link, since they now represent almost half of the few 4,000 operational satellites and that they are particularly brilliant. I take a deep breath and think about how to discuss the cost we’re all going to have to pay for Starlink’s internet access.

I do not blame my neighbors for their choice. Here, as in many rural areas of North America, there is no not many access possibilities to the Internet, and given that many people are working and studying from home during the pandemic, we want to do everything to make our lives easier.

However, I know how high the cost could be. My article to appear in The Astronomical Journal presents predictions of what the night sky will look like if the satellite companies continue with their current projects. I also know that due to the light geometry of the Sun and orbits chosen, the 50^and the northern parallel, where I live, will be the most severely affected part of the world.

In the absence of regulation, I know that in the near future a point out of 15 visible in the sky will be a satellite moving inexorably, and not a star. This will be disastrous for astronomical research and completely change the night sky around the world.

In order to determine how much the night sky will be affected by sunlight reflected from future satellite megaconstellations, we designed a free computer model to predict the brightness satellites as seen from various places on Earth, at different times of the night and in different seasons. We have also created a simple web app based on this simulation.

Our model uses 65,000 satellites in the orbits of the four megaconstellation companies: SpaceX Starlink and Amazon Kuiper (United States), OneWeb (UK) and StarNet/GW (China). We have calibrated our simulation to match the telescopic measurements of Starlink satellites, because they are by far the most numerous.

star link has made some progress in dimming the glare of its satellites since their first launch, but the most are still visible to the naked eye. Our simulations show that, from anywhere in the world, in any season, we will be able to see tens or even hundreds of satellites for at least an hour before sunrise and after sunset.

At present, it is relatively easy to escape the light pollution city ​​to benefit from a starry sky while camping or going to a chalet, but, according to our research, we will not be able to escape this new light pollution satellites anywhere on Earth, not even at the North Pole.

The hardest hit places on Earth will be at 50 degrees north and south, near cities like London, Amsterdam, Berlin, Prague, Kiev, Vancouver, Calgary and my home. At summer solstice, to these latitudes, nearly 200 satellites will be visible ateye naked all night.

I study the dynamics orbital of the Kuiper belt, composed of small bodies that lie beyond Neptune. My research is based on wide-field and long-term images duration exhibition to discover and follow these small objects to learn more about the history of our Solar system.

Telescope observations, which are essential to the knowledge of our universe, are about to become immensely difficult to succeed due to the unregulated development of space.

Astronomers are developing reduction strategies, but they will require time and effort that megaconstellation companies should assume.

Environmental costs

Internet by Starlink may seem cheaper than other options in rural areas, but that’s because you offloads many costs. One of them is the atmospheric pollution caused by the hundreds of launches of rockets necessary to build and maintain this system.

Each deployment of satellites sends rocket parts and other debris onto a low earth orbit already crowded, which increases the risk of collision. A part of these space debris will eventually fall back to Earth, and the regions of the Planet with the highest density of satellites will be the more at risk of impact.

Starlink plans to replace each of the 42,000 satellites after five years of operation, which will require de-orbiting an average of 25 satellites per day, or about six tons of material. The mass of these satellites will not disappear — it will be dispersed in the upper layers of theatmosphere. As satellites are mainly composed ofalloys ofaluminum, they risk forming particles ofalumina by vaporizing in the upper atmosphere, which could destroy ozone and cause global temperature changes.

This question has not yet been studied in depth since low Earth orbit is not subject to any environmental regulations.

rule the sky

At the moment, low Earth orbit, where all these satellites are expected to evolve, is almost unregulated. There are no standards for light pollution, air pollution caused by launches, air pollution caused by re-entry into the atmosphere, and collisions between satellites.

These megaconstellations may not be financially viable in the long term, and internet access speeds may drop significantly when many users connect at the same time or if it rains. Yet satellites are being launched at a breakneck pace right now, and the damage they cause to the night sky, the atmosphere, and the safety of low Earth orbit will not be erased, even if the companies go bankrupt.

There is no doubt that in many places people in rural and remote areas have been left behind in the development of Internet access. But there are many other options that do not entail such high costs. We cannot accept the global loss of access to night sky, which human beings have been able to observe and with which they have been able to connect since the beginning of their existence.

If the companies cooperated instead of competing, there could be far fewer satellites in orbit. Changing the design of the satellites could make them much dimmer, which would lessen their impact on the night sky. We shouldn’t have to choose between astronomy and the Internet.

However, without regulations that require change, or a strong pressure of consumers that demonstrates the importance of the night sky, our vision of stars will soon be changed forever.