Darkened SpaceX Satellites Can Still Disrupt Astronomy, New Research Suggests (gizmodo.com) 64
"SpaceX's attempt to reduce the reflectivity of Starlink satellites is working, but not to the degree required by astronomers," reports Gizmodo:
Starlink satellites with an anti-reflective coating are half as bright as the standard version, according to research published in The Astrophysical Journal. It's an improvement, but still not good enough, according to the team, led by astronomer Takashi Horiuchi from the National Astronomical Observatory in Japan. These "DarkSats," as they're called, also continue to cause problems at other wavelengths of light [and] were included in a batch of satellites launched by SpaceX on January 7, 2020. The new study aimed to evaluate the effectiveness of that dark coating...
The scientists found that the "albedo of DarkSat is about a half of that of STARLINK-1113," as they wrote in their paper. That's a decent improvement in the visual spectrum, but still not great. What's more, problems persist at other wavelengths. "The darkening paint on DarkSat certainly halves reflection of sunlight compared to the ordinary Starlink satellites, but [the constellation's] negative impact on astronomical observations still remains," Horiuchi told Physics World. He said the mitigating effect is "good in the UV/optical region" of the spectrum, but "the black coating raises the surface temperature of DarkSat and affects intermediate infrared observations."
A third version of Starlink is supposed to be even dimmer. Called "VisorSats," they feature a sun visor that will "dim the satellites once they reach their operational altitude," according to Sky and Telescope. SpaceX launched some VisorSats last year, but the degree to which their albedo is lessened compared to the original version is still not known, or if these versions will exhibit elevated surface temperatures.
Horiuchi told Physics World that SpaceX should seriously consider lifting the altitude of the Starlink constellation to further reduce the brightness of these objects.
. The article ends with a quote from an astronomer at Harvard-Smithsonian Center for Astrophysics and an expert on satellites. He'd told Gizmodo's reporter back in January of 2020 that "SpaceX is making a good-faith effort to fix the problem," and that he believes the company "can get the satellites fainter than what the naked eye can see."
The scientists found that the "albedo of DarkSat is about a half of that of STARLINK-1113," as they wrote in their paper. That's a decent improvement in the visual spectrum, but still not great. What's more, problems persist at other wavelengths. "The darkening paint on DarkSat certainly halves reflection of sunlight compared to the ordinary Starlink satellites, but [the constellation's] negative impact on astronomical observations still remains," Horiuchi told Physics World. He said the mitigating effect is "good in the UV/optical region" of the spectrum, but "the black coating raises the surface temperature of DarkSat and affects intermediate infrared observations."
A third version of Starlink is supposed to be even dimmer. Called "VisorSats," they feature a sun visor that will "dim the satellites once they reach their operational altitude," according to Sky and Telescope. SpaceX launched some VisorSats last year, but the degree to which their albedo is lessened compared to the original version is still not known, or if these versions will exhibit elevated surface temperatures.
Horiuchi told Physics World that SpaceX should seriously consider lifting the altitude of the Starlink constellation to further reduce the brightness of these objects.
. The article ends with a quote from an astronomer at Harvard-Smithsonian Center for Astrophysics and an expert on satellites. He'd told Gizmodo's reporter back in January of 2020 that "SpaceX is making a good-faith effort to fix the problem," and that he believes the company "can get the satellites fainter than what the naked eye can see."
Re: Elon 'the new messiah' Musk (Score:3)
Self evidently he does care or he would not bother to reduce the albedo of these sats at all.
Also, anyone who knows Musk will tell you he doesnâ(TM)t care about money beyond it being a vehicle to his goals. Many will disagree with those goals but suggesting profit is his motive is ignorant.
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Don't raise the satellites (Score:2)
Raising the orbit of these satellites would not benefit astronomers in the long run. If there was a malfunction of the satellite such that it could not deorbit under its own power, it would would still come out of orbit and burn up in a relatively short time. But if the orbit were raised as suggested, the satellite (or the pieces remaining after an explosion or collision) would stay in orbit much longer (maybe for thousands of years, depending on the altitude). That would eventually cause a much bigger
Musk will help astronomers (Score:2)
Astronomers are being very short sighted about this. (pardon the pun) They are trying to protect Earth based astronomy which is not that great anyway due to atmospheric interference. SpaceX will in the near future offer low cost launches of space-based observatories that will far surpass the ones on Earth. The future of astronomy is in space.
Yes, it is also important for individuals to use small telescopes or just the naked eye to enjoy the heavens. But that type of viewing is not going to be disturbed
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Astronomers are being very short sighted about this. (pardon the pun) They are trying to protect Earth based astronomy which is not that great anyway due to atmospheric interference. SpaceX will in the near future offer low cost launches of space-based observatories that will far surpass the ones on Earth. The future of astronomy is in space.
Astronomers have overcome most of the disadvantages of the atmosphere with adaptive optics and computer control and are now able to image things visually with similar resolution to Hubble.
Saying that astronomers should just to do all their observations in space reveals complete ignorance of costs. Space observatories are more than an order of magnitude more expensive that an advanced ground based one, and the launch costs are just a footnote on the whole bill. The Spitzer Space Telescope for example cost US
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Earth based astronomy might not be great due to the atmosphere, but its what 99.9% of *professional* astronomers have access to - even with SpaceX's fantastic price-to-orbit, you aren't going to be able to give even a majority of professional astronomers access to space based systems over the next 100 years. Plus someone still has to pay for that.
If you ignore that, then you are basically saying its OK to harm astronomy for the next however long it takes to replace that ability with space based platforms.
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A Mars settlement has the potential to be incredibly profitable.
Citation needed. Or at least an explanation of the claim that passes basic arithmetic skills and does not rely on science fiction.
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If you can't figure out how settling new territory with unexploited resources could be incredibly profitable then you're either being disingenuous or are beyond help.
In other words, you were not sayin' just sayin'
We have to figure out exactly how this windfall will be made. What are the resources on mars that can be profitable to send back to earth? How will it be collected and processed if we are going to do this. What will be the launching and re-entry costs? Then what are the resources on Mars that will be profitable for use on Mars.
Otherwise you're acting like my wife when she gets pissed at me, I ask her what's wrong, and she says "If you don't know, I'm not g
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Re: Musk thinks there's profit on Mars. (Score:2)
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Musk thinks there's enough money to be made on Mars that people will be able to get loans for their tickets.
Sorry for not providing a more detailed answer I'm not going to take your bait for a long drawn out debate where I will provide detailed information and you use short and simple messages to prompt me into providing ever more detailed explanations until I am tired and bored with nothing to show for it and you can gloat to yourself about how you got me to waste a bunch of time by posting short and simple challenges to my effortful comments. I've done this before.
In other words you have absolutely zero idea of how any profit can be made, But you just know. Okay, you gave me your answer.
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Musk also thought that firing pods full of people down vacuum tubes at 700mph would revolutionise transport. It hasn't and there's not only no sign it ever will, but also good evidence that Hyperloop will never deliver anything.
Not everything Elon Musk thinks of is practical or a good idea. If you want to exploit resources on Mar, you've got to factor in the costs of getting the mining equipment and personnel out there and getting the mined resources back to Earth, which will be considerable.
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Your conclusion that his motive is not profit assumes that his goal of settling Mars is not motivated by profit. A Mars settlement has the potential to be incredibly profitable.
How? Perchlorate mining?
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A Mars settlement has the potential to be incredibly profitable.
What? Have they discovered sources there of eternal life, cheap fusion energy and FTL travel? Because that's the only way a Mars colony would ever be viable, let alone profitable. You know that there's no atmosphere and even the soil is toxic, right?
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Hello Bot
Telco or Russia?
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This statement is true, but it glosses over the the issue. Economic value is, nevertheless, one kind of value that can be extracted from the space commons. The question isn't does one thing have value and one thing does not. The question is how can we accomodate competing interests in a way that balances costs and benefits fairly.
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Comment removed (Score:4, Interesting)
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The effect of astronomy on future extraterrestrial prospecting.
As far as our Solar System is concerned, you most likely can't beat cheap interplanetary probes for that purpose...which could be developed with SpaceX's satellites as a starting point. It's just easier to get way closer.
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That means a lot of data is generated by a lot of different point of views, creating a massive amount of data. This makes it easier to detect falsified data if it can't be corroborated by the many other people that have looked at the same part of the sky at the same time.
You could say something similar about dash cams in cars. Why do you need your own crappy one in your care if some large institutions could provide some superior surveillance tech?
I'
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Satellites have a lot of economic value. Earth based astronomy is fine but what value does is actually have over space based astronomy?
The fact that we can afford to do it. Space based astronomy is astronomically more expensive, by a factor of ten or more. Who is going to pay for it?
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ground based astronomy is at itâ(TM)s end (Score:5, Insightful)
SpaceX is at least working to reduce the albedo. What happens when we have satellites from organizations / countries that donâ(TM)t give a fig about astronomers? Eventually there will be too many of these to make ground based astronomy practical.
Realistically we need a plan to put way more space based telescopes up beyond these constellation to continue research - thatâ(TM)s what astronomers should be focusing on.
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I see this often, but it is not realistic at all.
Ground observation has to continue for various reasons. One of them is that you can only launch so much aperture in orbit. James Webb Telescope has been under construction for a very long time, and has to fold its mirror, and unfold it unattended (and not servicable). Anything larger th
Astronomy will eventually move to space (Score:4, Insightful)
Terrestrial communications are of vastly greater economic value. It's not even close. We have millennia to explore space.
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And then BOOM. Bye Bye Dinosaurs.
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High speed broadband is irrelevant to a lot of human beings too. If SpaceX wanted to do something "for humanity", they'd be working on a project to provide clean drinking water to everybody. They aren't doing that because people will actually pay them money to be able to download cat videos and pornhub quicker.
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"thousands of star systems are lost to us forever due"
Us? As in, future generations millions of years from now? All presuming we get FTL travel worked out?
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Not true. The nearest big galaxy to us is the Andromeda galaxy (two million light years) and it's actually getting closer and is predicted to collide with our galaxy. The longer we delay, the more likely the billions of star systems in it are to be in our grasp.
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Terrestrial communications can just use wires/fibers. Like they have in the past and works really well.
Dear Elon (Score:2)
As a compensation, please provide us with free real time video looking both up and down from all satellites. Thanks ;)
Darksats are not the plan (Score:5, Interesting)
Blaming the wrong people (Score:1)
Fuck off with this (Score:2, Insightful)
I never see these so called âoeastronomersâ (who somehow hate the space industry trying to be able to fund journeys to the planets) ask for clouds to be eliminated, birds to be shot, or air traffic be halted. Clouds, birds, and airplanes are unpredictable and considerably fatter and slower than satellites, whereas satellites can be predicted to the millisecond and exact location weeks in advance. Just turn off the telescope for the fraction of a second it will be in view should the field of view g
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That's not how telescopes work.
Even low orbit birds (such as the ISS) are visible an hour or more after full darkness (and the opposite at dawn) at ground level. Birds higher up (a substantial portion, if not a majority of some constellations) are visible much later
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That's not how telescopes work.
LOL did someone tell you they are using film or something? Or do you have proof that their sensors can't be turned on an off? What does it do when a bird, cloud, or airplane crosses the path? Will it explode or something?
If you can't cover the sensor, just ignore the data stream plus or minus 50 milliseconds FFS. Granted I don't do anything high-falutin' but most of the time I take short exposures on my telescope and use registax. I wouldn't be surprised if they do something similar or worse given they have
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Here in reality, birds don't glow at night, and neither do clouds or planes. Most all big scopes are sited, deliberately, in areas that have a minimum (or none) of all three.
Again, not how telescopes work. They accumulate photons across periods from minutes to hours. You can't simply stop the electrochemical processes in progress inside the
Vantablack (Score:1)
Coat the satellites with Vantablack.
Bigger problems on the ground (Score:2)
Most (nearly all) interesting optical astronomy is better done from space. This has been true for 50 years at least, and we've seen this play out with instruments like Hubble.
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most optical astronomy is done from the ground, where you can get both more light gathering and larger baselines (and therefore, resolution), and get a pretty good instrument built for well under a billion dollars. (in fact, by total observation time, I'd guess that "most" optical astronomy is probably done on instruments costing under $20,000. There are still discoveries being made by amateur astronomy. The sky is vast).
The benefit of space is avoiding effects of the atmosphere such as absorptivity and dis
Gizmodo now the news site of record ? (Score:2)
Gizmodo ?!
Can they spell their own names nowadays ?
I had to stop reading Gizmodo because of the gross - and uncorrected - errors in almost every story they post.
Worse than Slashdot, seriously.
Spare me (Score:2)
How much are the Telcos and CableCos paying for this?
Such obvious tactics are quite detectable.
AT&Trolls go away.
SOME astonomers ==Luddites (Score:4, Insightful)
After Hubble got its first set of contact lenses [wikipedia.org] it became clear that ground-based astronomy was entering the nursing home. Astronomers have had nearly 30 years to come to grips with this and re-focus on new designs for new space-based and lunar-based observatories, which are superior in every single way except for maintenance accessibility, and work to obtain funding to build and launch them. Instead of doing this, the community has followed to diverging and destructive paths:
Some have embraced the future but decided to push exotic and expensive one-off programs like JWST that are unique designs, hand-built, taking decades to develop, build, and test (long enough to be the entire career of a handful of astronomers) and eat up most available funds producing a single instrument that can be wiped out by a single launch failure, or crippled by a single deployment or operational upset.
Others have decided to keep building and operating ground-based telescopes, but then shake their fists at the sky and curse as modern technologies like light bulbs make it glow at night, and satellites and aircraft fly over their instruments. Their own lack of ability to adapt to the future is, for some reason, more important than the general public's ability to reap the benefits of new technology. Their inability to move the public to support them on this is exactly because they cannot explain to the public why a new ground-based photo of a distant galaxy (which we probably already have poor photos of that did not benefit anybody) is more important than a new internet solution that would improve the education, employment, banking, communications, entertainment, etc of millions of people. There is, further, no explanation to the public for why it should say "no" to better internet connectivity when that new photo of a distant galaxy could be obtained at far higher quality from a space-based telescope - and no reason given for why THEY should pay for any of it (in fact, the entire community cannot explain to the taxpayer why he/she needs to pay for any of this since it provides the average citizen with no perceptible benefit beyond spiffy pictures on web sites or in big glossy coffee table books).
The astronomy community would be better served by NOT doing idiocy like JWST and instead agreeing upon a standard design of some Hubble-like telescope, then getting them produced in a quantity of identical units and getting them launched on future SpaceX Starship launches. With a fleet of identical observatories, above the atmosphere and most satellites, astronomers could schedule observation time on whichever satellite was available and best oriented without regard to the specifics of the telescope, and production times and costs would be vastly lower (launch costs would also be lower). The eventual other ideal solution is radio and optical telescopes on the lunar far side, where light and radio signals from Earth are blocked, no Earth orbiting satellites or aircraft overfly, and servicing and even direct observations would eventually be possible by astronauts based on the lunar surface.
The very presence of Earth's atmosphere puts a natural limit on ground-based astronomy, so it was always destined to become obsolete - some people just keep clinging to the past and are now turning against progress because of their own focus on a bit of out-dated technology.
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Only to those blissfully innocent of any actual knowledge of astronomy.
Space based designs are inferior in a
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I don't want a future where simple astronomy isn't something you can do in the backyard with your kids using simple equipment.
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Look nobody is saying don't launch sattelites, what they are saying is work with the Astronomy community to minimize the negative effects. So far Musk and Starlink have been doing the bare minimum, just to pretend they care about the issue
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I hope the next major asteroid impact event lands on your house.
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After Hubble got its first set of contact lenses [wikipedia.org] it became clear that ground-based astronomy was entering the nursing home.
Is that why Hubble is now outdated and greatly surpassed by numerous ground based telescopes that would be exceptionally difficult and expensive to put into space? Why are billions being spent on ground based astronomy still if what you say is true? I guess you think you're the smartest person in the room.
It's called progress (Score:2)
Get used to it. Ask the guy, maybe he'll send up a space telescope for shared use?
Really? (Score:2)
What about planes? There are 10.000 of those flying around as well and they are bigger and nearer and not painted black on the underside.
Well.... (Score:1)