Tuesday, January 31, 2023

Astronomer warns 1 out of every 15 lights in the sky could soon be a satellite

I am on my rural farm in Saskatchewan, chatting with neighbors whom I have invited to admire the night sky through my telescope.

After exclamations and open-mouthed surprise over the rings of Saturn and the light that has traveled in space for over two million years to reach our eyes from the Andromeda Galaxy, our conversation inevitably turns to the pandemic, our work from home, and complaints about the rural internet. My neighbor casually mentions that they just switched to using Starlink for their ISP.

I look up and notice a bright satellite moving across the sky, almost certainly Starlink, as they now account for almost half of the nearly 4,000 active satellites and are very bright. I take a deep breath and think carefully about how to negotiate the substantial costs we all have to pay for Starlink Internet.

I don’t blame my neighbors for switching. Here, as in many rural North America, there are no great internet access options, and since many people work and take lessons from home during a pandemic, anything that makes life easier is immediately accepted.

But I know exactly how high this price is. My upcoming article Astronomical journalThere are predictions about what the night sky will look like if satellite companies fulfill their current plans.

I also know that due to the geometry of the sunlight and the chosen orbits of 50 degrees north latitude, where I live will be the most severely affected part of the world.

Without any rules, I know that in the near future, one out of every 15 points you see in the sky will actually crawl relentlessly over satellites, not stars. It will be devastating to astronomical research and will completely change the night sky around the world.

The future is too bright

To find out how strongly the night sky would be affected by sunlight reflected from planned satellite megaconstellations, we built an open source computer model to predict the brightness of satellites as seen from different places on Earth, at different times of the night, in different seasons.

We also created a simple web application based on this simulation.

YouTube video

Our model uses 65,000 satellites in orbit registered by the four giant constellation companies: SpaceX Starlink and Amazon Kuiper (USA), OneWeb (UK) and StarNet / GW (China). We calibrated our simulation to match the measurements of the Starlink satellite telescopes, as they are the most abundant.

Starlink has so far taken some steps towards dimming its satellites since their first launch, but most of them are still visible to the naked eye.

Our simulations show that from anywhere in the world, at any time of the year, tens to hundreds of satellites will be visible, at least an hour before sunrise and after sunset.

It’s relatively easy right now to avoid urban light pollution for dark skies while camping or visiting your hut, but our simulations show that you can’t avoid this new satellite light pollution anywhere on Earth, even at the North Pole.

The most heavily affected places on Earth will be in latitude 50 degrees north and south, close to cities such as London, Amsterdam, Berlin, Prague, Kiev, Vancouver, Calgary and my own home. On the day of the summer solstice, about 200 satellites will be visible with the naked eye from these latitudes all night long.

I am studying the orbital dynamics of the Kuiper Belt, the belt of small bodies beyond Neptune. My research relies on long exposure wide field imaging to detect and track these small bodies to learn about the history of our solar system.

Telescope observations, which are the key to studying our universe, will soon become much, much more difficult due to the unregulated evolution of the cosmos.

Astronomers are devising some mitigation strategies, but these will take time and effort, which must be paid for by the constellation’s giant companies.

Unknown environmental costs

Internet from Starlink may seem cheaper than other rural options, but this is because many of the costs are not covered. One of the immediate costs is air pollution from the hundreds of rocket launches required to build and maintain this system.

Each satellite deployment dumps spent rocket bodies and other debris into already loaded low-earth orbit, increasing the risk of collision. Some of this space debris will eventually fall back to Earth, and those parts of the globe with the highest satellite density will likely be literally affected as well.

Starlink plans to replace each of the 42,000 satellites after five years of operation, requiring an average of 25 satellites per day, about six tons of material. The mass of these satellites will not go anywhere – it will be deposited in the upper atmosphere.

Since satellites are composed primarily of aluminum alloys, they can form alumina particles when they evaporate in the upper atmosphere, potentially destroying ozone and causing global temperature changes.

This has not yet been deeply studied because no environmental regulations currently apply to low-earth orbit.

By adjusting the sky

Currently, the low Earth orbit in which all these satellites are planned to operate is almost completely unregulated. There are no regulations regarding light pollution, air pollution from launches, air pollution from reentry, or collisions between satellites.

These mega-constellations may not even be financially viable in the long run, and internet speeds can slow to creep when many users are connecting at the same time or when it is raining.

But companies are launching satellites right now at a frantic pace, and the damage they are doing to the night sky, atmosphere, and safety in low-Earth orbit will not be reversed even if operators go bankrupt.

There is no doubt that rural and remote Internet users in many places have been left behind by the development of Internet infrastructure. But there are many other options for online delivery that do not incur such huge costs.

We cannot come to terms with the global loss of access to the night sky, which we have been able to see and keep in touch since we were human.

With cooperation, rather than competition between satellite companies, we could have a lot less in orbit. By changing the design of the satellites, you can make them much weaker and less affect the night sky. We don’t have to choose between astronomy and the Internet.

But without rules requiring these changes, or strong consumer pressure to point out the importance of the night sky, our view of the stars will soon change forever.

Samantha Lawler, Assistant Professor of Astronomy, University of Regina.

This article is reprinted from The Conversation under a Creative Commons license. Read the original article.

Nation World News Desk
Nation World News Deskhttps://nationworldnews.com
Nation World News is the fastest emerging news website covering all the latest news, world’s top stories, science news entertainment sports cricket’s latest discoveries, new technology gadgets, politics news, and more.
Latest news
Related news