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SpaceX and Starlink change the night sky quickly



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This image of a distant galaxy group from the Lowell Observatory in Arizona is affected by the traces of the Starlink satellites by diagonal lines shortly after their launch in May.


Victoria Girgis / Lowell Observatory

The astronomer Cees Bassa spends a lot of time working with advanced radio telescopes for space. However, on May 24, 2019, he stepped outside near the famous Dutch Dwingeloo Radio Observatory and instead pointed a small video camera at the night sky.

It was more than sufficient to take a train with over 50 bright lights moving in formation. This was one of the first recordings of the SpaceX Starlink constellation. The company launched its first full batch of 60 broadband satellites less than 24 hours ago.

SpaceX wants to send thousands of satellites into orbit close to Earth to provide broadband Internet access that anyone can connect to (at a price) from almost anywhere.

Bassa enthusiastically tweeted the video and called it a "fantastic view" and "a must see".

But then he started running the numbers. He calculated that once about 1,600 Starlink satellites are in orbit, up to 15 of the bright lights will be visible in much of Asia, North America, and Europe for most of the night in summer.

"Even in spring, autumn and winter, around half a dozen Starlink satellites are always visible up to three hours before sunrise and three hours after sunset. Depending on how bright they are at the end of the day drastically affect the character of the night sky, "he wrote in May.

In late 2019, it became clear that the Starlink satellites are more reflective than SpaceX or astronomers expected.

"What surprised everyone was the sheer brightness," said Jeffrey C. Hall of Lowell Observatory reporters at a meeting of the American Astronomical Society in January.

With SpaceX 60 more satellites are to be launched on Sunday 300 by next week the revolving router in the sky. The company is targeting almost 1,600 by the end of 2020. And this is just the beginning.

SpaceX has the thumbs up from the FCC to launch a total of nearly 12,000 satellites and has submitted filings to the International Telecommunication Union indicating that it may wish to launch an additional 30,000 .

For a small context, it is estimated that mankind has launched fewer than 9,000 satellites since the 1950s.

Bassa provided the numbers for the FCC-approved Starlink constellation in full size as well as for smaller satellite fleets planned by OneWeb and Amazon. He found that the number of satellites visible in the night sky increased roughly in proportion to the total size of the constellations. So if SpaceX recognizes the full scope of its Starlink ambitions without figuring out how the satellites can become less bright, we can assume that almost 100 points of light will fly across the night sky at almost any time.

Recent simulations have shown that even with 25,000 satellites in orbit close to Earth, the vast majority are too weak to be seen with the naked eye, but considerable uncertainty remains.

"The appearance of the pristine night sky, especially when viewed from dark places, is still changing because the new satellites could be significantly brighter than existing artificial objects in orbit," the International Astronomical Union said in a statement from February 12, in which the results of the simulations were announced.

SpaceX did not immediately answer a number of questions related to this story.

Since Starlink satellites interfere with astronomical observations at this very early stage, there was an outcry from astronomers and a promise by SpaceX to work with scientists and scientists to remedy the situation. An experimental "DarkSat" with a coating that should reflect it less was started with a batch of Starlink satellites but it is unclear whether the approach can work.

The dark coating can cause the satellite to absorb more solar heat and ultimately not work properly. When Bassa tried to watch the DarkSat in January, it didn't appear to be much weaker than its uncoated Starlink siblings. Other astrophotographers, including Thierry Legault, have recorded similar observations in the video below. Bassa hopes to get another look at what's going on with the experimental satellite soon, but told me that the weather has not been cooperative so far.

SpaceX has also worked on software that allows observatories to plan their astronomical observations to avoid Starlink satellites.

"However, some observatories may not be equipped to use such a software program," says a FAQ on their International Astronomical Union website. "If the number of satellites gets too high, avoidance programs may not work as effectively as intended."

There are other concerns.

Managing an unprecedented amount of orbital traffic is a high stakes game. A small number of accidental collisions can lead to dozens of debris, which then cause more collisions. In the worst-case scenario
known as Kessler Syndrome
cascading collisions make orbit an inaccessible wasteland and block access to space and our global telecommunications networks.

SpaceX and others are committed to managing their satellite traffic responsibly and proactively, including the requirements of regulators to orbit out-of-service satellites so that they burn safely in the atmosphere.

But it did not take long for Starlink to cause fear among other orbital operators. A Starlink satellite from the first batch launched in May came a little too close to a satellite of the European Space Agency in September and for the first time forced ESA to perform a "collision avoidance maneuver ".

The constellations continue to increase.

SpaceX has launched new batches of uncoated, highly reflective Starlink satellites every few weeks, and its competitor OneWeb is also expanding its own satellite deployments. Despite protests from astronomers who have started to publish open letters and circulating petitions, space companies have strong incentives to rapidly expand their satellite constellations in the meantime.

On March 29, 2018, the FCC SpaceX gave the green light for the start of the first phase of Starlink with 4,425 satellites. However, this approval assumes that half of these satellites will be launched and operational within six years. This means that SpaceX will have to launch almost 2,000 more satellites over the next four years, or about 40 per month, provided each satellite it launches reaches its operational orbit and works without incident.

This explains why SpaceX didn't just stop pausing while figuring out how its satellites can be less reflected. Presumably there is also pressure to be one step ahead of the competition, as rival OneWeb begins to introduce its own broadband constellation and Amazon's Kuiper project is waiting in the wings.

There could also be pressure to benefit from the upcoming 5G gold rush. While Starlink will sell retail Internet access to customers through its own proprietary receiver, like other satellite ISPs, Musk has suggested that Starlink could also sell wholesale or backhaul Internet access to 5G carriers.

More recently, Gwynne Shotwell, COO of SpaceX, has suggested that the company may be looking to outsource its Starlink business. SpaceX already has a sister company, SpaceX Services, which, according to the latest FCC documents, operates Starlink's ground stations.

"Right now we're a private company, but Starlink is the right kind of business we can go public," Shotwell told a group of private investors last week, according to Bloomberg.

Enthusiasm for a possible IPO is another reason why the pace of Starlink launches is unlikely to slow down so quickly.

The Case in Court

The tension between the rush to send thousands of satellites into orbit and the outcry over their unintended consequences suggests that the problem must be resolved immediately in court.

A trio of Italian astronomers, led by Stefano Gallozzi from the Astronomical Observatory in Rome, recently wrote a scientific paper suggesting that the United States government could be sued by another nation before the International Court of Justice under the 1967 Space Treaty , [19659006] The logic here is that, according to the treaty, each country is ultimately responsible for satellites launched by private entities on their territory. Because SpaceX is an American company, the U.S. government is technically responsible to the rest of the world for everything SpaceX does in space.


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Look at this:

Are SpaceX Starlink satellites ruining the night sky?



2:57

However, to sue the US government in The Hague, the US would have to submit to the jurisdiction of the International Court of Justice. Space law experts consider this highly unlikely.

"The chances of another state bringing the United States to the International Court of Justice are slim and will be less sued under the space treaty," said Michael Listner, a lawyer specializing in space law and policy.

Meanwhile Joanne Gabrynowicz, emeritus editor-in-chief of the Journal of Space Law, says that the Starlink space contract and other constellations that affect astronomers' work is still almost impossible to bring the issue to an international court. 19659051] "Article 9 of the Space Treaty states that signatories need to avoid harmful interference in the use of space by other signatories, so the question is how much light pollution is harmful," she told me.

There are some precedents in US law for the control of retail companies that are trying to change our view of space from the ground up. A section of the US code specifically prohibits "intrusive space advertising," so it would probably not be advisable for SpaceX to use images of its satellite trains moving across the sky in Starlink marketing materials.

A New Operating Environment

The legal community has other rumors about Starlink and its effects on how we get starlight on Earth.

Ramon Ryan, a law student and new editor-in-chief of the Vanderbilt Journal of Entertainment and Tech Law, has investigated the novel topic and believes the FCC may have violated a federal environmental law when it gave SpaceX permission, one to launch unprecedented number of satellites. He explains the argument in a long article, the draft of which he gave me and which is to be published in the magazine this summer.

The FCC has for years assumed that commercial satellites have no adverse environmental effects and are therefore categorically excluded from the detailed environmental assessments required by the National Environmental Policy Act.

Interestingly, NASA does not exclude its launches from the environmental review, although it streamlines the process by using a single review to cover similar routine launches. Ryan suggests that the FCC might be wise to adopt NASA's approach and consider the environmental impact of satellite constellations.


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Check it out:

SpaceX launches the first series of Starlink satellites



7:05

"A court would likely find that the FCC is required to review commercial satellite projects at [the National Environmental Policy Act] because these projects are likely to have direct, indirect, and cumulative environmental effects," Ryan writes.

"We strongly reject this theory," an FCC spokesman told me. "The FCC's measures to unanimously approve the SpaceX deployment were entirely lawful. The ordinance contains numerous legal grounds based on public records, which, moreover, did not include comments as part of this subsequent criticism."

However, Ryan suggests that the FCC could environmental test frequently used satellite components. Satellite operators could then design their constellations to pass this boilerplate assessment, avoiding a potentially lengthy review of their specific project.

"In this way, the FCC would create standards in the commercial satellite industry that would promote economic growth and stability while fulfilling Congress's mandate to the federal government to proactively consider the environmental impact of its actions," concludes Ryan.

No such legal challenges against Starlink or other competing satellite constellations have been filed.

According to the FCC, Listner and other legal experts, SpaceX followed the letter of the law to get Starlink on its way. The company has also worked with groups of astronomers to address their concerns, though it has no legal obligation to do so.

Some astronomers even argue that Starlink's promise of broadband internet access could be worth the cost of science to almost any location.

"We have the choice of either denying people the Internet … and denying them educational, financial and other opportunities (or making it easier for people to do ground-based astronomy," writes astronomer Pamela Gay. "Yes, the sky will be full of satellites, but which is the bigger good?"

It is a debate that is likely to continue for many months and years.


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