Report: Astronomy threatened by satellite constellations
A report issued today, resulting from a video conference of astronomers in July, has concluded that much of ground-based astronomy is threatened by the new large satellite constellations being launched by SpaceX, OneWeb, and others.
The astronomers’ report offers six solutions for solving the problem.
- Launch fewer or no LEOsats. However impractical or unlikely, this is the only option identified that can achieve zero astronomical impact.
- Deploy satellites at orbital altitudes no higher than ~600 km.
- Darken satellites or use sunshades to shadow their reflective surfaces.
- Control each satellite’s orientation in space to reflect less sunlight to Earth.
- Minimize or eventually be able to eliminate the effect of satellite trails during the processing of astronomical images.
- Make more accurate orbital information available for satellites so that observers can avoid pointing telescopes at them.
Notice what solution they don’t offer? Maybe astronomy should focus on building space-based telescopes, where the view would be clear, unimpeded by both the satellites and (much more importantly) the atmosphere.
In fact, the claim in the first solution above, that launching no satellites is “the only option identified that can achieve zero astronomical impact” is intellectually dishonest. All astronomers have to do is get their observatories into space, something that is very doable and affordable with today’s cheaper launch capabilities and technology. In space the impact of the satellites will once again be zero. And they will have the added benefit of getting outside the atmosphere, which by the way is actually a bigger limitation to observations than any satellite constellation.
It seems to me that this report was written by the faction of astronomers who make their living building big ground-based telescopes. Rather than think of solutions, they want to protect their turf by attacking the achievements of others.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
A report issued today, resulting from a video conference of astronomers in July, has concluded that much of ground-based astronomy is threatened by the new large satellite constellations being launched by SpaceX, OneWeb, and others.
The astronomers’ report offers six solutions for solving the problem.
- Launch fewer or no LEOsats. However impractical or unlikely, this is the only option identified that can achieve zero astronomical impact.
- Deploy satellites at orbital altitudes no higher than ~600 km.
- Darken satellites or use sunshades to shadow their reflective surfaces.
- Control each satellite’s orientation in space to reflect less sunlight to Earth.
- Minimize or eventually be able to eliminate the effect of satellite trails during the processing of astronomical images.
- Make more accurate orbital information available for satellites so that observers can avoid pointing telescopes at them.
Notice what solution they don’t offer? Maybe astronomy should focus on building space-based telescopes, where the view would be clear, unimpeded by both the satellites and (much more importantly) the atmosphere.
In fact, the claim in the first solution above, that launching no satellites is “the only option identified that can achieve zero astronomical impact” is intellectually dishonest. All astronomers have to do is get their observatories into space, something that is very doable and affordable with today’s cheaper launch capabilities and technology. In space the impact of the satellites will once again be zero. And they will have the added benefit of getting outside the atmosphere, which by the way is actually a bigger limitation to observations than any satellite constellation.
It seems to me that this report was written by the faction of astronomers who make their living building big ground-based telescopes. Rather than think of solutions, they want to protect their turf by attacking the achievements of others.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
I waiting for Space-X to announce that they will add small, light weight telescopes to the outward facing side of every Starlink starting with number 3000 or so. And offer the network to convey the data.
I’m a little baffled by all the apparent hype over this supposed huge astronomical crisis. (Not to speak the stupendous tragedy of earthlings never seeing the real stars again — meep! — Not!) Yes, as noted above, astronomers can simply move their serious next-generation telescopes into space. But way beyond that, why can’t earth-based astronomy simply wait for the Starlink et al. satellites in near-earth orbit to slide into earth’s shadow every night? Doesn’t that inevitably happen every evening no later than about 9:00 p.m.? (And ending about 3 a.m.?) Have astronomers do their astronomy then! (What am I missing?)
Michael McNeil: What you are missing is that these satellite constellations will essentially cover the globe. They will always be in the sky because there are so many of them. SpaceX is launching over 4,000, OneWeb almost 1,000, and if Amazon goes forward that another 5,000 satellites.
They will cover the globe, but they will still fall into shadow at sometime.
More accurate info regarding what is currently in the sky is needed.
Put into a good program, it can be used to filter the data.
But I also agree that space based astronomy is the way to go.
Terrestrial based observation and research will eventually be pointless. Maybe not now. May not 20 years from now, or 100 but eventually SATs, spacestations, perhaps vessels will be so numerous to make it so.
As I was reading I was thinking the same. Use this as a reason to innovate and get lenses in space.
You’re not missing anything. You have it right.
Even if they quit launching star link satellites, Russia and China and India and Japan and the EU will continue to fill the skies with their own technology before the competition catches up.
I look at this as a competitive move to put pressure on SpaceX, in a underhand way, to hobble “unfair superior advantage” in the space competition.
Just as Russia takes out ads in the United States to stop fracking.
The Hubble telescope should’ve been retired years ago. It’s replacement (or many replacements) should’ve been in place already. It’s contribution far exceeds anything Earth-based and has proven that this “old technology” to be superior to anything on the ground.
When SpaceX launch a tesla into the deep black, I thought it was pretty cool until I realized the lost opportunity for a university to place something fantastic into deep space for free! whether it be a telescope, early warning radar using modern spy equipment, solar wind/radiation monitoring as well as a large “tesla battery” power supply to operate it all including the cameras that watch the effects of deterioration of the Tesla and its interior when exposed to space. A publicity stunt “muskprobe” that everyone would still be talking about as the new information gathered would be freely available to classrooms and universities from the SpaceX website on a daily basis…
Like all of those huge empty aluminum bottles attached in the space shuttle that was forced back into the atmosphere to burn up when they could’ve been used for a thick walled heavy duty living space or a space station, what a wasted opportunity…
I’m hoping the segments of the telescope, meant for Hawaii, can be fit on a rocket, launched and be assembled in orbit geosynchronous above Hawaii in the Pacific. That would be karma.
I have always supported a Far Side Lunar Observatory. A combined facility of deep space optics, solar observatory, and radio telescopes, an FSLO should be robust, can be just as automated as a Hubble or James Webb telescope.
Long term maybe even add arrays for radio interferometer observations.
For half the lunar day they can study the Sun. For the other half they can see and listen to the cosmos with no atmosphere, no light and no rf noise from Earth.
An FSLO is the kind of mission to the moon we need. Not just flags and foot prints, but a permanent observatory. Land the the equipment. Land the men to assemble it, and turn it on.
It is a lot of hardware, but I honestly believe it is achievable in the next 20 years with the launch tech we have, and are currently developing.
I would not be surprised if Elon Musk suggests, off planet telescopes as a solution to this problem. Imagine launching multiple Hubble sized telescopes (or larger!) and not having to rely upon a costly SLS mission. Perhaps SpaceX could launch the telescopes for free; adding a nice logo and naming rights to the scope and leasing time to various institutions around the world. (Soon, Hubble may also be revived significantly using satellite recovery drones being currently tested.)
Also a nice alternative to the issues encountered from pagan, rock worshipers who inhabit isolated pacific islands…
Question: What is the shape of the impact craters on the moon?
Could they be used as a “primary” mirror in very large telescope?
Perhaps not at the visible spectrum but some other?
Elon is committed to a Mars mission. (Apparently, so is Donald Trump according to Eric Trump Who was just speaking about it in the convention) Everything he does has this goal in mind ultimately.
Most of the stuff he will need for the journey is too bulky to take with him so he needs the ability to create tools and infrastructure from raw materials available in his environment. 3-D printing machines that can form tools from meteorites, bricks/cement and mirrors from sand.
A variety of heavy equipment will need to be learned then programmed and construction demonstrated proof of reliability on the moon. Setting up the infrastructure in a base there will prepare them for what is needed to be successful on Mars in a new environment to survive on minimal resources and energy.
I don’t picture this lunar base to be a small venture. Expanding, improving, becoming self-sufficient for whomever can afford the transportation fees. I visualize a spacecraft hopping from one location to the next placing newly created telescopes and sensing equipment in strategic locations furthering science for many years to come paving the way to a permanent colony.
After all, with enough large telescopes, will never be blind again. The sun can only shine on one side of the Moon at a time…
Michael McNeil asked: “why can’t earth-based astronomy simply wait for the Starlink et al. satellites in near-earth orbit to slide into earth’s shadow every night?”
This is what the altitude limitation is all about. The higher the altitude the longer into the night that the satellites remain in sunshine. Astronomers already have limitations due to geostationary satellites, as they are so high that they are sunlit almost all the time, despite being in equatorial orbit.
Since these new satellite constllations tend to be in high inclination orbits, there are times of year in which their orbits will remain in sunshine even longer in the higher latitudes, so northern and southern observations can become more problematic. Since there are so many different orbital planes, this problem can remain for much of the year near either pole. Lower orbits makes this less of a problem.
I am not overly sympathetic toward these astronomers, since I, too, believe that space-based astronomy is preferable to ground based astronomy. However, NASA’s horrific management of the great space telescopes could be scaring astronomers (e.g. Webb, WFIRST, and even Hubble went over budget), and can anyone blame them?
In the past two or three decades, smaller space telescopes have returned a lot of excellent astronomy, and once the astronomy community gets over the fact that for decades they haven’t been looking through the eyepiece — and don’t need to — they will come to realize that space based is far superior to having to wait for nightfall on clear nights with good viewing, which isn’t really all that good even without city lights nearby.
I can’t wait for some amateur to embarrass the professional astronomers by putting up a hobbyist smallsat telescope that beats many of the professional ground-based telescopes.
Since ground based scopes use adaptive optics driven by computer, it should be possible to also use a wide field eye to “see” an interloper coming into the field of view, and close the shutter on the main scope until it passes. Most exposures are very narrow fields of view over long time frames. For large field view exposures this is more problematic, for example the near earth object surveys.
Hubble was a one and done project of phenomenal success, but was never designed to be serviced in orbit by service satellites. Today it can be done. I suggest a fleet of telescopes, varying in size, all engineered to be serviced in orbit. As the cost per launch keeps going down, we may reach a point where orbit service cost would be more expensive than replacement. Hubble was also designed to survey many wavelengths with different cameras. We could instead distribute the wavelength window to different scopes in orbit, each one more task specific. This would simplify design costs and hopefully add to service life.
I can see the day when a private telescope (not NASA) will reach orbit.
Astronomers..A bright bunch, but they forgot to look around and see what is going on. They are way late, but they are setting the stage to push for more funding. That is what all of this is about.
I’m rather surprised that Musk..engineer and marketeer, hasn’t already come up with a scheme to inexpensively revive Hubble.
Gary: These astronomers are not so bright. First, if they were really setting the stage for more funding they would have included in their list of solutions the launching of space-based telescopes. That’s where the new funding is really needed. All their other “solutions” either required limiting what others can do or some relatively minor adjustments to what they do.
This same astronomical community also pushed for both the Webb and Roman telescopes, big space boondoggles that have prevented the construction of numerous more productive but less expensive space telescopes while endlessly going over budget and being delayed.
This same astronomical community also propsed in the early 2000s, when they pushed for Webb, to literally abandon Hubble and do no more repairs to it. It sounds insane but that is exactly what they recommended.
As for Musk, he I think has enough on his plate, though if some smart astronomers did propose something intelligent I am sure he would listen.
All good points, but there is hope. I have a patient, where we went off on a tangent. I mentioned that 45 years ago I was allowed to resurrect an ancient 5″ Clark refractor, which was sitting on top of a UC Berkeley building. She informed me, that she was now in charge of the new telescope, which was sitting on top of the new building. She is an undergraduate student that overflowed with energy when discussing all things astronomy/physics. Later, I found out that she was a member of the Harvard team that “imaged” a black hole. She also was sent by the university to various conferences..as a speaker. If this is the future of astronomy..it will be full of discovery. She was absolutely amazing.
SpaceX is experimenting with a sun-shade on some of the latest Starlink satellites. Also, I think some are being painted with non-reflective coatings. (?)
Astronomers against spaceflight? What a horrible thing!
Of course, the cure is to launch the telescopes to space. Not to retrograde into Aristotelian status quo assumptions. JHC!
I’ve read stories of astronomers bothered by squirrels, or some wild life like that, climbing into their telescopes and found sleeping on their mirrors. Astronomers need to keep up with things, not dream back to the age of Galilei but with a bigger lens. “Black out all the cities!” “Forbid all satellites!” That’s not the way forward for astronomy, That’s just lazy.
Another alternative is to install tiny telescopes on the LEO satellites and point them all to the same star observation. They do this already on the ground telescopes.
I must admit that this problems does not affect my own amateur astronomy: the viewing of distant galaxies (100-500 million light years) or nebulae and globular clusters.
However, my photographic friends indicate they have the software to eliminate the satellite trails.
Increased satellite presence may impact them more.
The cost analysis of adaptive optics vs space based telescope needs attention, IMHO.Potato Scab
Then there is the geopolitical aspects. Hawaii is no longer a feasible option. Chile is an unknown with the current anti-American trend worldwide. Space based astronomy circumvents these considerations.
For every problem, there is an opportunity!
“This same astronomical community also pushed for both the Webb and Roman telescopes, big space boondoggles that have prevented the construction of numerous more productive but less expensive space telescopes while endlessly going over budget and being delayed.”
Part of the probem is that while these people may be very good astronomers, they’re not engineers.
The other part of the problem is the general trend toward gigantism in major observatory development. It’s not that telescopes on these scales don’t provide real advantages – they do – but that they do suck up vast amounts of funding, and they do come with opportunity costs. And obviously it’s much easier, even so, to built a gigantic observatory on a Chilean mountaintop than it is in space.
If Webb works out, it will certainly offer unprecedented capabilities. But we’re also tying up the cost of two (actually, almost three) America-class amphibious assault ships, complete with air wings, in a vehicle we cannot service, and on which every component must deploy perfectly and work perfectly; and if it does not, we just deployed the most expensive piece of space junk in human history. Whereas an America has a crew that can fix minor things that break, and can easily come into port for a refit or an overhaul whenever it needs one.
Max,
“Even if they quit launching star link satellites, Russia and China and India and Japan and the EU will continue to fill the skies with their own technology before the competition catches up.”
That’s the thing: Pandora’s Box has been opened. It can’t be closed. There is far too much money, and far to much strategic value, in these constellations. Astronomy simply lacks either. So the astronomers are going to lose this battle, even if they somehow manage to shut down Starlink, which of course they won’t.
Because they won’t restrain foreign players like the Chinese from deploying these constellations in the 2020’s and 2030’s.
So they can figure out a way to adapt, or suffer.
I do not see any reference to the “occultation problem”, which does not go away just because the satellite is in the Earth’s shadow, is sunshades or dark colored. Even a small satellite in Earth orbit can completely occult (obscure) a distant star, even if only for a few microseconds. It seems unlikely, but could an effect interfere with advanced astronomical measurements?
These astronomers are probably looking at the huge investments that have recently been made in extremely, exceptionally and amazingly large ground based telescopes and have a not unreasonable expectation that time on space based scopes will not be available for most astronomers for a decade or more. So they’re focusing on the next decade or two rather than what the opportunities will be for them in SBA in the more distant future.
Elon’s new business venture, if as successful as hoped, will surely cut deep into the profits of terrestrial internet/cable service providers and dry up a big chunk of their revenue streams. Soon, a day will come when the terrestrials realize its either change or die, and they are forced to evolve to remain competitive. What will their new incarnation look like? Can they re-invent themselves to the point where the constellations of satellites lofted by Elon and others become redundant and/or obsolete and no longer appeal to the majority of Internet users (ala Direct TV)? Or will Elon be seeing a StarLink dish on most U.S. houses and buildings very soon?
Gary wrote: “I’m rather surprised that Musk..engineer and marketeer, hasn’t already come up with a scheme to inexpensively revive Hubble.”
Musk has other goals, among them is reducing the cost of getting into space to a level where other people can afford to be the problem solvers. Musk and SpaceX need not, cannot, and should not be the solvers of all space problems. That is the direction of a monopoly, which only solves the problems that it wants solved, and limits the resources that are available for problem solving. Notice that the NASA monopoly does not solve many problems.
Richard M noted: “If Webb works out, it will certainly offer unprecedented capabilities. But we’re also tying up the cost of two (actually, almost three) America-class amphibious assault ships”
Forget the assault ships. Webb is so over budget that we should be getting nine or ten Webbs out of this one telescope. Seven or eight, if we include launch costs. The lost opportunity costs are tremendous, and the overruns scare the astronomers from putting telescopes into space, creating yet another loss of scientific advancement. Webb and Roman (previously WFIRST) are disasters of such magnitude that even if they work as promised they set back astronomy and science in ways that are hard to express.
When Lyman Spitzer conceived the idea of telescopes operating in outer space, I’m sure he did not think that they would end up being so poorly managed that they prevented other scientific exploration.
Ray Van Dune,
You asked: “Even a small satellite in Earth orbit can completely occult (obscure) a distant star, even if only for a few microseconds. It seems unlikely, but could an effect interfere with advanced astronomical measurements?”
Do you mean any more than existing twinkling/seeing affects measurements? No, not at all.
Tom wrote: “Elon’s new business venture, if as successful as hoped, will surely cut deep into the profits of terrestrial internet/cable service providers and dry up a big chunk of their revenue streams.
This assumes a zero sum game, but Starlink could open up additional markets that feed back into existing systems and markets. Starlink’s target customers are those who do not have ready access now.
On the other hand, two or three years ago, the existing geostationary satellite (GEO) companies became so worried about the effect of the several proposed communication constellations that they ordered fewer GEO satellites. They, and we, will have to wait to see how this market shakes out.
Webb is so over budget that we should be getting nine or ten Webbs out of this one telescope. Seven or eight, if we include launch costs. The lost opportunity costs are tremendous, and the overruns scare the astronomers from putting telescopes into space, creating yet another loss of scientific advancement.
How many more Kepler missions could we have gotten for the cost of the Webb overruns?
The one thing I could think of Musk doing it integrating a simple radio link into his satellite network.
Then every smallSat could be linked into the network for easy access to every scientist around the world.
@pzatchok
The problem is not that astronomers don’t know when they are where. That’s
ephemeris, the very foundation of astronomy since thousands of years. They really keep track of that, trust me, or rather them! The problem is that the reflected light of the things blank out big chunks of the sky the telescopes are observing. They destroy the feint light beams from the most distant. No mending is possible.
Like pointing a flashlight into your backyard telescope. Even if you know exactly where the flashlight is, it doesn’t help. Image destroyed.
Still, I prefer spaceflight before ground based astronomy. Astronomers find ways around it, in orbit literally.