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Comment by 1053r | Hacker News Reader

Cheap space launch is the cause of, and the solution to, our light pollution issues.

50,000 satellites would be impossible to launch without the recent step change in the wholesale price of launch. And even 5% of that number of space based telescopes will decrease the contention for valuable instrument time enormously.

Particularly if the next generation space based telescopes used tethers or precision formation flying for extremely large simulated aperture size, we'll start getting phenomenally amazing data. (Even some of the largest ground based telescopes will be possible to compete with in space using large formations of connected satellites.)

So all of the hue and cry around Starlink is really just growing pains. It will hurt some of the science temporarily (particularly around sunrise and sunset), but in the long run, cheap launch is really what the field of astronomy needs to continue to have better and better instrumentation.

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That may be true for NASA and maybe the wealthiest and most connected universities and research centers. But that doesn't really help smaller universities or amateur astronomers.

Not to mention that getting a telescope the size of the Keck telescopes into space probably won't be feasible for a long time (although without air pollution you would get similar quality with a slightly smaller telescope). And even ignoring the cost of launch space telescopes are likely more expensive due to needing to deal with the extremities of space like temperature regulation and dealing with cosmic rays (which besides interfering with the computers, also cause noise in the CCD cameras).

> That may be true for NASA and maybe the wealthiest and most connected universities and research centers.

I work at a well funded university, and it's not true for us, either. In fact I haven't met a single astronomer who is optimistic that somehow we'll magically get enough money to replace even a small fraction of the great telescopes we currently have on the ground.

They were also pessimistic and dismissive of Starlink and SpaceX’s launch capacity when first announced.

"They"? Are astronomers a uniform community in which the entire profession is responsible for every stray comment someone makes?

In this case, comments they DIDN’T make. The FCC had a public comment period before Starlink was approved for launch and no one pointed out the problem for ground optical astronomy.

Are you sure? Is this the same FCC that ignored the fact that most of the comments against network neutrality were astroturfed?

Yes, I’m sure. The astronomy community was silent.

They were too busy looking the basement for the permits that were "on display in the bottom of a locked filing cabinet stuck in a disused lavatory with a sign on the door saying ‘Beware of the Leopard'".

So that means they are disqualified from commenting on the problem now? It was not clear how bright these things were going to be on orbit with the publicly available information at the time, and SpaceX obviously did not consider the impact.

Also the number went way up, and the orbits changed.

And the FCC has no rules about light pollution. Which is the reason we should have a global debate about it.

Radio astronomers did complain right away and got a sensitive part of the Ka band left unused -- it wasn't included in the reserved bands but has become important since. Very nice of Starlink to grant that request.

I'm pretty sure I saw concerns from the astronomical community before launch. Maybe they just weren't aware of the process to complain, or didn't know about the threat until after the comment period had closed.

We have to take in consideration that we are weighting space exploration against the comfort of a minority of hobiists. Do you want a thousand people to take pretty pics of the sky, or millions to have rural internet ? I agree we should make sure we don't destroy the night sky view for the naked eyes, but I'm ok with having to see a satellite through my telescope when I look at venus. Not a big deal, and not important to humanity.

Large constellations of satellites providing internet signal has nothing to do wiht space exploration though.

As an independent company it wouldn't, but as part of SpaceX, Starlink is meant to provide funding for Starship, which has a lot to do with space exploration. Not only Mars trips but anything anyone else wants to do at $50/kg to LEO.

What is the goal of SpaceX to be the ones actually doing the exploring, or just hiring themselves to be the means to which others can do the exploring? If the latter, then the hiring of SpaceX should be the source of funding. If the former, then they are going to be needing a helluva lot more cash than monthly subscription fees for internet service will ever provide.

As a sidebar/tangent, I see SpaceX/Starlink being the first company to actually get close to putting their Adams-esque customer service department on a different heavenly body than earth. "For all Starlink service requests, please visit our offices in person. Our offices are conveniently located in the Sea of Tranquility, practically visible to everyone one most nights."

To be fair to hobbyists, they contribute significant discoveries even in modern times. Far from pretty pictures of the sky.

https://en.wikipedia.org/wiki/Amateur_astronomy#Discoveries_...

Also I'd expect having an amateur community will feed people into a stronger professional community. While not on the same scale, consider taking the same its just hobbyists approach to software dev vs just leave it to the big guys like FB/Google.

Edit: Spelling/clarity

> getting a telescope the size of the Keck telescopes into space probably won't be feasible for a long time

SpaceX is said to be discussing making a telescope out of a dedicated Starship. To simplify the telescope, and periodically return for maintenance. Like the telescopes of NASA's Scientific Balloon Program.

Except... Starship User Guide gives a payload envelope of 8 m diameter, and "100+" metric tons to LEO. Launch cost is TBD, but $30M would be failure (similar to Falcon 9 internal cost), and $2M is said to be an aspirational goal. Which is what a balloon flight costs, for a day or so, a few tons, and couple of meters of mirror.

So 8 m to Keck's 10 m. Half the area. But with balloon speed-tape (aerospace gaffers tape) pragmatics, not Webb insanity. Although... how about a "simple" pivot-out-to-hex of 20+ m diameter?

Starship changes the constraint envelope by multiple orders of magnitude. And that's starting to be reflected in strawman project sketches. Which seem low visibility for now. But unless something goes seriously wrong, very won't be in not a long time. (Edit: removed a misleading sentence).

> reflected in strawman project sketches

Do you have a link to some of them?

Sorry, I don't. It's not something I follow, and with access to campuses still restricted, I've only the occasional stumbled-on gossip to go on. That last "Monster submarine surfacing" sentence was excessive. And calling $30M failure, given the difference in payload mass, was just silly. I was tired, and should have punted or pruned the comment.

> So 8 m to Keck's 10 m

No need to stop at one. Build hundreds, put them in orbit around the sun and turn them into an array capable of imaging exoplanets.

> hundreds [...] into an array

Or even just a few. :) A constraint is that optical-frequency interferometry arrays need to directly combine the input light, rather than being able to sample and simply combine data, as with radio frequencies. So optical telescopes would need to be docked. But yes, if both launch and instrument costs dramatically decline, "can I have two? four? eight? more?" becomes a fun question. At a minimum, as launch and recovery becomes inexpensive, there's less point in leaving a backup instrument warehoused on the ground.

I understand the aesthetic argument against this the most.

The weakest argument seems to be the one saying that having satellites in space will help even the smallest universities. It will probably be cheaper for ones with no/old telescopes to split time on one in space than build one from ground that can't find anything new anyway.

First of all, small ground telescopes, ones that are cheaper than a single sattelite launch, can still do plenty of meaningful research.

And timesharing a telescope doesn't work well for certain kinds of research. For example if you want to observe a set of object every night to watch for variability, having a ground telescope you have complete control over is probably better than trying to get the timeslot you need on a space telescope every night for however long you need.

time slot could be "every moment for 200 days" or it could be "two hours every day for a year"

I'm not going to try to BS my way into pretending like I'm an expert but I do find it to be a safe bet to think that in 20 years it will not be cheaper to have the world's best telescope makers come to whatever random city you are in around the world to help you set up - instead of one amazing telescope maker making 1000 on an assembly line and firing them all off

Many space telescope discoveries are followed up on with ground telescopes. Kepler and TESS planets are not confirmed until a second telescope sees the dip, and that's cheapest to do with ground telescopes.

> But that doesn't really help smaller universities or amateur astronomers

And the harm is... some long-exposure photos will have a small aberration if they don't compensate digitally. In exchange, fast Internet access continues to be limited to select areas or the extremely wealthy.

Just too faint for the naked eye to see is actually really, really bright compared to a lot of astronomical objects of interest. Enough that it could easily saturate a long exposure, and depending on how close it gets to the target, completely ruin the frame.

Fortunetely, that's less of a problem in the middle of the night, bu there is something else that worries me. What if far from sunrise or sunset the sattelite occludes an object you are observing, without leaving a trail? Hopefully, statistics would level that out, but with enough of these sattelites, the chances of that happening go up, and it may lead to incorrect results.

Agree, I think the smart move for SpaceX is to stay ahead of it by offering/working out/subsidizing assembly line style space telescope production and launch w/ benefits to impacted astronomy programs.

I mean imagine if you just enabled a high quality ~cell phone camera in each direction on the existing starlink array etc. Or what if starlink specified a parasite satellite slot that they sold e.g. you can put up x mini sats embedded and facing space with network and power port. It lasts as long as the node lasts, put up a lot and don't complain.

I'd love to see more emphasis on smaller, more numerous space telescopes. JWST will be great when it launches, and it's impossible to overstate how awesome Hubble has been, but space is big and time on these largest scopes will be very valuable.

There's a ton of work being done on ordinary 1m and smaller telescopes. As you say, space has big advantages in atmospheric, temperature, sun, and weather factors that may allow a smaller orbiting telescope to do work that would require a larger terrestrial scope. I'd love to see enough scopes in space that (1) ordinary Astro 102 students could do a lab assignment to point a satellite-based telescope at an object and take an image and (2) researchers could have more frequent surveys of the sky to find transient objects.

The decreasing wholesale price of launch should also make cleanup relatively easy compared to other areospace marvels.

There are solutions from lasers (photon momentum), to nets that capture debris and then add a sail to it to increase friction from the atmosphere that is still in play in low earth orbit:

(https://www.youtube.com/watch?v=MwBRqHqmkCo)

I'm build a dedicated observatory in my back yard? how the hell does this help me do better at astronomy?

That might be a possible future, but why is starlink required in that process? I can definitely see a future where we have space telescopes without giant satellite swarms obstructing the view from Earth.

Because Starlink finances the development of cheap launch, a demand driver NASA can’t replicate.

Does it, though? Is the total addressable market for internet access large enough to support Starship development?

Yes - order of $30B / yr, larger than NASA budget.

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