Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

How bad are satellite megaconstellations for astronomy?

leonarddavid.com

Post reply on HN
Print view View original

21–30 of 197 posts

Re: How bad are satellite megaconstellations for astronomy?

#21

Post by ketralnis »

marcosdumay wrote: post #10
delichon wrote: post #3

On the one hand the constellations are doing considerable damage to surface based astronomy. On the other hand they are funding an enormously lower cost of access to orbit and beyond for astronomy up in the sky.

Yes, the future of astronomy is in space. If the satellites don't disrupt it, light pollution will anyway, or best case, it will be disrupted by atmospheric pollution. There's no lack of clear skies in space.

A: yeah we're hurting you but if we didn't, B & C would

B: yeah we're hurting you but if we didn't, A & C would

C: yeah we're hurting you but if we didn't, A & B would

I guess it’s nobody’s fault then

Re: How bad are satellite megaconstellations for astronomy?

#22

Post by delichon »

Cacti wrote: post #14
delichon wrote: post #3

On the one hand the constellations are doing considerable damage to surface based astronomy. On the other hand they are funding an enormously lower cost of access to orbit and beyond for astronomy up in the sky.

Is this something we have evidence for, or is this just in theory?

SpaceX built the biggest constellation to date, and is using the profits to build Falcons while designing Starships. Check out the resulting cost per kilo to orbit:

https://ourworldindata.org/grapher/cost-space-launches-low-e...

That's pretty good for theory.

Re: How bad are satellite megaconstellations for astronomy?

#23

Post by iwontberude »

ericd wrote: post #11
tetris11 wrote: post #2

I know it's a blessing for people who live out in the sticks to have internet.... but is that really such a large use-case to justify entire fleets of these things? How hard is it to run km of wire from the nearest town? To me, these were built for the sole purpose of surveillance, and internet is an afterthought. Edit: yes yes it's expensive, but the easiest solution the world came up with was for some guy to invest…

Yeah, I’m not sure why trenching is so expensive, I think PG&E was quoting something silly like millions per kilometer. I’m planning on doing like a tenth of a kilometer in a day with a $400 trencher rental pretty soon. I’m sure it’s not apples to apples, but the delta there seems pretty baffling. For me, the biggest hang up has just been that I’m required by the state to get it inspected before I put in the conduit,…

It might cost money to figure out where to prioritize resources

Re: How bad are satellite megaconstellations for astronomy?

#24

Post by runeofdoom »

jonplackett wrote: post #9

Is this a bit of a temporary problem, in the the very technology causing the issue - substantially cheaper access to space - will presumable ultimately put a frikkin massive telescope, or many massive telescopes into orbit where they’ll also not have to deal with the many other issues ground telescopes have to deal with. I get that this still sucks for any individual with a Telescope though.

It's not just "any individual with a telescope" though. It's stuff like the Simonyi Survey Telescope, a set to map the southern sky down to below 27th magnitude that's in trouble.

Re: How bad are satellite megaconstellations for astronomy?

#25

Post by LeoPanthera »

Havoc wrote: post #13

As much as I sympathize this feels like a necessary evil to me in a sense vaguely accerlationism like. I do think starlink can do more to help the situation though. Sure they tweaked some of the satellites to minimise it, but they could do more. Presumably the know the precise location and orientation of each sat. Surely that can be packaged into a data stream that helps unfk the images? Maybe with a sprinkling of th…

There's no need to predict them in advance. Astronomy photos taken from the ground aren't one long exposure. They're lots - hundreds even - of short ones, which are then "stacked" to reduce noise and increase dynamic range of the final image.

It should be trivial to identify streaks in the stack and just throw out those images. I'd be surprised if they're not already doing that for the older satellites up there, and things like planes flying across the shot.

Re: How bad are satellite megaconstellations for astronomy?

#26

Post by bmitc »

marcosdumay wrote: post #10
delichon wrote: post #3

On the one hand the constellations are doing considerable damage to surface based astronomy. On the other hand they are funding an enormously lower cost of access to orbit and beyond for astronomy up in the sky.

Yes, the future of astronomy is in space. If the satellites don't disrupt it, light pollution will anyway, or best case, it will be disrupted by atmospheric pollution. There's no lack of clear skies in space.

That needs some citations. The James Webb Telescope's mirror is 6.5m in diameter. It took decades and billions of dollars of overruns and a prayer to launch and work correctly. There is no hope of most hardware repairs.

That mirror size pails in comparison to what can be accomplished via ground based observatories for much, much cheaper.

And the available modes of operation are completely different between space and ground. For example, space observatories are using decades old instrumentation techniques, hardware, and software. And that's just for starters.

We cannot do astronomy via space exclusively.

For me personally, I never wanted to see something like Starlink with my bare eyes, and I have several times. It's beyond annoying to me that a company has been able to unilaterally pollute the Earth's sky.

Re: How bad are satellite megaconstellations for astronomy?

#27

Post by bmitc »

delichon wrote: post #22
Cacti wrote: post #14

Earlier quoted context omitted.

Is this something we have evidence for, or is this just in theory?

SpaceX built the biggest constellation to date, and is using the profits to build Falcons while designing Starships. Check out the resulting cost per kilo to orbit: https://ourworldindata.org/grapher/cost-space-launches-low-e... That's pretty good for theory.

The theoretical part is whether that's actually useful for not. Cost per kilo to orbit doesn't magically solve astronomical observation problems.

Re: How bad are satellite megaconstellations for astronomy?

#28

Post by _dain_ »

bmitc wrote: post #26
marcosdumay wrote: post #10

Earlier quoted context omitted.

Yes, the future of astronomy is in space. If the satellites don't disrupt it, light pollution will anyway, or best case, it will be disrupted by atmospheric pollution. There's no lack of clear skies in space.

That needs some citations. The James Webb Telescope's mirror is 6.5m in diameter. It took decades and billions of dollars of overruns and a prayer to launch and work correctly. There is no hope of most hardware repairs. That mirror size pails in comparison to what can be accomplished via ground based observatories for much, much cheaper. And the available modes of operation are completely different between space and…

> That needs some citations. The James Webb Telescope's mirror is 6.5m in diameter. It took decades and billions of dollars of overruns and a prayer to launch and work correctly. There is no hope of most hardware repairs.

Because it had to get launched folded up, because the launch vehicles were so space- and mass-constrained. The unfolding mechanism was enormously complicated and added to much of the cost.

Now we can send up bigger, heavier objects for much less money. The 6.5m mirror fits comfortably inside Starship's cargo bay, unfolded. JWST is a one-off clockwork masterpiece; future space telescopes will come off an assembly line. There will be thousands in orbit, pointed at every part of the heavens simultaneously.

Re: How bad are satellite megaconstellations for astronomy?

#29

Post by Starlevel004 »

tetris11 wrote: post #2

I know it's a blessing for people who live out in the sticks to have internet.... but is that really such a large use-case to justify entire fleets of these things? How hard is it to run km of wire from the nearest town? To me, these were built for the sole purpose of surveillance, and internet is an afterthought. Edit: yes yes it's expensive, but the easiest solution the world came up with was for some guy to invest…

[flagged]

Re: How bad are satellite megaconstellations for astronomy?

#30

Post by bmitc »

oh_my_goodness wrote: post #16
tetris11 wrote: post #2

I know it's a blessing for people who live out in the sticks to have internet.... but is that really such a large use-case to justify entire fleets of these things? How hard is it to run km of wire from the nearest town? To me, these were built for the sole purpose of surveillance, and internet is an afterthought. Edit: yes yes it's expensive, but the easiest solution the world came up with was for some guy to invest…

Hard enough that some people are putting up satellites instead. EDIT: Say there's some way to put in fiber at $10k per km. Even then, ten million users at 1km per user makes $100 billion.

To me, these are capitalistic solutions looking for problems. It's the whole startup mentality. Let's just throw a bunch of shit in space and see if it ends up being useful for anything. This idea of connecting the world is as false as the other hundred millions times that's been sold.
Post reply on HN