SpaceX upgrades Starlink to reflect less light, can't launch without its Starship SpaceX's has big claims that its second-generation Starlink broadband internet satellites will slash light pollution on Earth, but there's one big catch: they're apparently too heavy to launch. SpaceX satellites have drawn the ire of astronomers since their deployment in 2019. While they may not be completely ruining the …
They are a lot heavier, not just a bit. The ones currently in orbit are between 250kg and 300kg, the earlier ones didn't have the laser links so were lighter. The v2 satellites are 1250kg so 4 or 5 times more massive than the current ones, they're also twice as long so don't fit the fairing when flat and would have to be stood on end for launch on an F9.
So, basically, the light reflection mitigations have very little to do with the increase in mass. It's pretty much the entire Gen 2 design that's the problem in terms of launch mass. It sounds like they designed then with the expectation that Starship would be ready more or less on time.
Don't be misled by Pink Floyd, the far side of the moon is not dark, at new moon the back is pointing directly at the sun and with an orbital velocity in excess of 1km/second long exposures are not a option. (If you add the velocity of the Earth in too you have a total moon velocity varying between 29 and 31 km/s which makes target locking non trivial.)
There's a lot of crud hitting the moon all the time, while space telescopes can also be hit by space crud, they are not sitting on a dirty great rock distorting spacetime and attracting extra space crud.
While the moon has some advantages the disadvantages are far greater. Nice Big space scopes like JWST are the way to go.
And still does not address the problems caused for telescopes not operating in visible light. Radio telescopes are rendered almost useless when these things are in their field of view. When a receiver designed to pick up signals in the picowatt range suddenly gets a signal 14 or 15 orders of magnitude more powerful, the results are not pretty.
Perhaps the constellation companies should pay for a space based radio telescope that won't be affected by their satellites. As an alternative to switching off the satellite transmitters when over a radio telescope, it would probably work out to be the cheapest mitigation strategy.
That is true in their band of operation or observation, and the noise floor in those bands isn't going to be cleared with a magic wand even if you shut starlink down. Nor is the 2.4 band going to be magically clean if you banned home wifi from using it. Outside the those bands the interference drops off markedly, and is readily filterable.
While these issues are real concerns, they need to be balanced against the benefits of alternate uses. Science and military radars aren't the worlds only concerns, just important ones. Maintaining technical advancements in communications and keeping the Viasat/Hugesnet duopoly in check are also important, as they are currently the main lifeline of essential communications to the majority of the earths surface*. Remember the aftermath of the Tonga eruption.
*Surface != land area. We have oceans and ice flows in addition to the landy bits.
"This is a real demonstration of corporate good citizenship...."
....necessitated by the preceding real demonstration of appalling corporate greed and bad citizenship by not giving a damn about the issues, accurately predicted by the astronomy community beforehand, and waiting until until 2,700 of the shiny blobs are already orbiting the earth before publicly acknowledging the problem. In July 22 alone 5 clusters of Starlink satellites were placed in orbit, averaging around 50 individual satellites per launch. Next cluster is planned for August 9th, and who knows how many more after that? Don't look up indeed.
And Musk's proposed solution - a bit of anti-reflective film, probably stuck on with space-gaffer tape, and a few dobs of black paint, with even these modifications making each satellite too heavy to be used with their current technology, so to be launched at an unspecified time in the future on a space vehicle which hasn't even flown yet.
Or in other words - let's put out a press release with some vaguely plausible actions which give the impression we're doing something but in reality we'll be able to launch the whole 10,000 shiny satellites in place without changing a thing - and don't mention the increasing risk of accidental collisions with other satellite systems potentially making low-orbit unusable for mankind in the future. But hey - loadsamoney.
Starlink satellites have a short lifespan (5 years) and fly incredibly low (essentially within the atmosphere); it's how they offer low latency and lower powered uplink hardware than the Internet satellites of old. A collision would actually result in a faster return to Earth because there would be no active station keeping on the debris and the drag:mass would be higher.
I'd also recommend re-reading the article. The modifications don't increase the weight appreciably, they're modifications to the next generation, which are heavier beasts.
"A collision would actually result in a faster return to Earth because there would be no active station keeping on the debris and the drag:mass would be higher."
Collusions can slow down bits of the satellites and accelerate other pieces sending them into unplanned and unknown orbits. With no way to track very small pieces, there is no way to get out of their way. A tiny piece of something was found to have gone completely through the mechanical arm of the ISS. When astronauts are performing spacewalks, they come across a bunch of new impacts since the last time somebody was outside.
"waiting until until 2,700 of the shiny blobs are already orbiting the earth before publicly acknowledging the problem."
Actually the current fleet already have exceptional measures installed to reduce their impact on astronomy because SpaceX have been listening to astronomers since before the first operational launches. The orbits were lowered so they spend less time sunlit over the dark side of the planet. Dark paint was already used and this report shows they have found something 10x darker. The satellites already face the edges of the solar panels towards Earth during the brief times that it matters. A visor was added to keep the Earth facing parts in shadow until a better solution was found for version 2 satellites. At the request of astronomers, the state vectors for Starlink satellites have been published during the ascent and descent phases instead of just for the operational orbits that are normally available.
"who knows how many more after that?"
Anyone who has read the publicly accessible filings.
In every possible way your comment shows an outstanding level of ignorance on this subject.
“In every possible way your comment shows an outstanding level of ignorance on this subject”
Hmm – the ameliorative actions you’ve mentioned regarding reducing the widely predicted issues affected astronomical observation all have one thing in common – they don’t work sufficiently, do they, otherwise the new set of proposals wouldn’t be necessary.
As for the final number of Starlink satellites planned to be placed in orbit, no definitive number has been released by the company. Their Wiki states: On 15 October 2019, the United States FCC submitted filings to the International Telecommunications Union on SpaceX's behalf to arrange spectrum for 30,000 additional Starlink satellites to supplement the 12,000 Starlink satellites already approved by the FCC. After that, who knows?
I would suggest as many as Musk knows they can get away with until the whole of low-earth orbit is saturated.
I note you don’t mention the elephant in the room – the incontrovertible fact that the bigger the number of satellites, the bigger the chances of low-orbit collisions. Mentioned in this BBC news article written 24hrs ago, https://www.bbc.co.uk/news/technology-62339835
there have already been a number of near misses involving Starlink satellites, including near misses with China’s space station. To quote Dr King of Portsmouth University “"If there are too many fragments (generated by collisions), it could make low-Earth orbit unusable in the future…. And we may not be able to get out of low-Earth orbit into higher orbits, where our navigational satellites and telecoms satellites are situated."
SpaceX's Starlink satellites alone are involved in about 1,600 close encounters between two spacecraft every week, that's about 50 % of all such incidents, according to Hugh Lewis, the head of the Astronautics Research Group at the University of Southampton, U.K. https://www.space.com/spacex-starlink-satellite-collision-alerts-on-the-rise
“These encounters include situations when two spacecraft pass within a distance of 0.6 miles (1 kilometer) from each other. And the situation is bound to get worse. Only (currently) 2,700 of an expected constellation of tens of thousands have been placed into orbit so far. Once SpaceX launches all 12,000 satellites of its first generation constellation, Starlink satellites will be involved in 90% of all close approaches, Lewis’ calculations suggest.”
Add another 30,000+ Starlink satellites into the mix and you don’t need the intellect of Elon Musk to work out what’s likely to happen.
They are a lot of objects in space from low earth orbit to geostationary orbit, some 26,000 objects are tracked ranging from Space Station, Satelites, Spent rocket stages and other debris. Sounds a lot but space is big with in GEO it's 266,947,554,950,031.00 cubic KM, on average each object in space has 9 billion cubic km of room.
Now density differs depending on the orbit but orbits themselves are like a motorway on earth each Satellite does the same speed on the same orbit, if they went faster or slower they would make their orbit lower or higher. So as a result it is like traffic going along a highway with a 3 meter wide satellite getting close to another satellite on another road 1 km away been classed as a close encounter which really it isn't.
Like today the closest conjunction is 2 satellites passing 0.117 km away with a 1 in 1000 chance of hitting.
https://platform.leolabs.space/visualizations/conjunctions/today
Now this looks a lot of objects, but remember these are not to scale and if they was you wouldn't see any.
https://platform.leolabs.space/visualizations/leo
The gen 2 Starlinks are bigger and heavier because they are vastly more capable than gen 1s, not because they added a coat of paint and some window tint film (ok fractionally heavier than without, but not really significant compared to the overall mass).
Certainly these teeny weeny weight gains aren't the reason they can't be launched by a Falcon.
Other satellites have had problems before and still do today and they haven't fixed them, like Iridium satellites that was so bright they you could see them with the naked eye when their antennas reflected sunlight > https://www.youtube.com/watch?v=uymzXNdXwmo . Some companies are now doing the same thing as SpaceX and are reducing the reflectivity.
The black material has "five-times lower specular peak compared to the darkest available space stable paint,"
Probably not as black as the inside of a coffin on a moonless night.
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"Isn't one of the main uses of Vantablack being for Satellites?"
A near perfect black paint on a satellite is going to lead to a massive heat problem. It's also going to be much easier for the sat to absorb heat from the sun than to radiate it away when it goes to the dark side of the planet. Even if the cycle was closely matched, the ramping up and down of the temperature through such an extreme causes metals to fatigue and parts to come loose.
To date, SpaceX has not crashed only one Starship shaped test article. They haven't tested it with its booster and they should be on special watch after being given another inappropriate approval to continue operations in Texas smack in the middle of several wildlife preserves and just a loud shout from an international border. Due to international agreements, the flight paths they can take from that location are severely restricted. Elon may have finally listened to his staff and that's why it's full speed ahead on constructing a duplicate launch facility in Florida. It remains to be seen how patient Kennedy Space Center and Cape Canaveral are with big things going boom all over the place if things continue in the same groove.
So far there hasn't been any talk about how the second stage of the Starship stack is going to deploy a pile of Starlink satellites. If they plan to recover Starship, they'll need a reliable way to open and securely re-close the bay so it can re-enter the atmosphere without tearing itself apart. The Falcon 9 upper stage is discarded with only the booster landing for reuse since it never gets to orbit or to orbital speeds. Elon's goal with Starship is full reuse of the whole stack. I see that as extremely ambitious at a time when he's also stating that SpaceX can't survive unless it's launching Starlink satellites on the Starship rocket. Maybe that's why his last funding drive failed to raise the amount of investment SpaceX was hoping for. Did they ever get back their $250mn investment in Solar City bonds? Has Elon been cashing out Tesla stock to prop up SpaceX? Inquiring minds would like to know.
"So far there hasn't been any talk about how the second stage of the Starship stack is going to deploy a pile of Starlink satellites"
Really? Have you not been paying any attention?
They're using something based on an industrial pallet stacker to release the satellites - been referred to as a pez dispenser for a while now.
"They're using something based on an industrial pallet stacker to release the satellites - been referred to as a pez dispenser for a while now."
I pay lots of attention.
IF they can get the satellites out and miss crashing into the nose cone doors, they still need to get those doors closed properly and latched so the second stage can re-enter the atmosphere provided they've been able to solve the problem of the heat shield tiles breaking off. If the second stage can't be buttoned up, it won't survive coming back down. What do they do at that point? Leave it in orbit to eventually come down somewhere? Do they aim for a little used tract of ocean and just let it breakup and let sink what doesn't burn up? There is a serious amount of engineering to be done. They don't even seem to be to the CGI rendering stage for some of it yet.
I'd love to get a bootleg copy of their financials and a breakdown of how much each Starlink/Starship deployment might cost. Guesses have been made, but not very good ones that I can tell.
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