from Hacker News

SpaceX satellites could blight the night sky, warn astronomers

by Cbasedlifeform on 5/28/19, 8:30 PM with 50 comments

• by autocorr on 5/28/19, 10:25 PM

  Obviously high-bandwidth satellite internet is important. Speaking from a place in the USA where we only have one option for pretty crappy DSL internet (at $60 a month), I would probably even be among the first to try and get it! Before you criticize scientists as having tunnel vision for attempting to stymie global world progress, consider that astronomers are not and have never been in a position to have any regulatory power on this issue. At most they can inform the public of the side effects.

  There was a similar situation when a Russian private company sent up a satellite that would deploy reflectors to purposefully make it one of the brightest objects in the night sky[1]. I image some astronomers breathed a sigh of relief when the reflectors didn't properly deploy.

  In radio astronomy, there are a few small protected bands to keep some portions of the spectrum quiet for scientific purposes. There is no such "spectrum allocation" for optical astronomy. Like chopping down the rain forest or putting plastic in the ocean, we may improve our quality of life through external costs. Governmental regulation permits us to partially control for these externalities. Perhaps if we find ourselves in a big mess like with CFC's and destroying the ozone layer, we will have a public call-to-action to create regulations.

  So, what's the rub? Ground based telescopes are vastly cheaper than space-based alternatives for optical and radio astronomy. The difference in cost is often more than two orders of magnitude. If ground based telescopes become less efficient or less productive, there will simply be fewer scientific discoveries made within a flat budget. If the public is required to increase the budgets of NASA, NSF, ESO, and ESA to maintain their desired level of scientific output, then that in itself is an external cost that SpaceX and other companies are passing on.

  [1] http://spaceflight101.com/soyuz-kanopus-v-ik/mayak/

• by nonnontrivial on 5/28/19, 9:40 PM

  Wondering if these satellites follow a fixed path. If so, and there are few enough of them, the nextgen land-based optical telescopes will just have to factor this into scheduling.

  Has SpaceX said anything about the paths they will follow? Can they change mid-deployment?

• by maxander on 5/29/19, 12:36 AM

  From a minute of googling, there’s roughly 5k satellites in orbit right now. Most of those are in a slightly higher orbit than Starlink’s (LEO) so they’re incrementally farther away, but would be in a better position to catch sunlight in the night sky.

  And yet I, probably like everyone else who isn’t an astronomy enthusiast, haven’t ever looked at a light in the sky and known it was a satellite. They’re subtle, not dominating the night sky by any means, at least insofar as an untrained modern human can tell. Starlink would up the number of satellites by ~2x, perhaps, but would that be enough to change the basic equation?

• by vikramkr on 5/28/19, 8:40 PM

  Is it worth protecting ground based astronomy here though? Obviously the science is immensely important, but so is the internet, I dont buy this idea about the lack of consensus being an issue. Certainly the scientists should have had their say, and perhaps this should have been put up for a more public debate before the project was initiated, but I don't think that the go ahead to the project should be contingent on consensus from the scientific community. It should be contingent on approval from a regulatory body that is appointed/controlled in some democratic way and reflects the will of the population, and if the benefits to society outweigh the risks, then it should get the go ahead regardless of consensus by astronomers.

• by tapvt on 5/29/19, 12:17 AM

  As a landowner in a dark sky zone, I can’t decide if the trade-off is worth it.

  It’d be nice to have Internet way out there. But at the cost of my (and everyone else’s) pure night sky?

• by errantspark on 5/28/19, 9:45 PM

  Someone ought to do a simulation of what this would look like with the full constellation. I love stargazing, I take days long trips to go to dark sites just so I can enjoy the sky. I imagine it would be quite beautiful to see that the implied lattice around the earth as sun glints off the solar panels.

  I'm personally so excited to see these, I think it will be a breathtaking, tangible emblem of one of the first planet-scale systems that humans have built.

• by sdinsn on 5/28/19, 10:02 PM

  > His estimates suggest that once the first 1,584 satellites are launched, for which the trajectories have already been made public, there will be about 15 satellites clearly visible above the horizon for three to four hours after sunset and before sunrise.

  Oh no, 15 tiny lights in the sky. Not really a blight.

• by AngryData on 5/28/19, 9:56 PM

  Wouldn't be a problem if we didn't let telecomms fuck us in the ass so badly that we need this.

• by floatingatoll on 5/28/19, 11:08 PM

  Has anyone yet built an AR simulator app of what SpaceX informs us will be their satellites’ visibility with correctly-aimed panels at various times of day, dusk, and night?

• by thecrumb on 5/28/19, 9:01 PM

  Not too worried about it. They have a shelf life and I imagine their design will improve over time.

  I'd rather see some regulations against all the lights in the Walmart/shopping mall/grocery store parking lots which have completely ruined the night sky in my area.

• by LargoLasskhyfv on 5/28/19, 10:38 PM

  One more reason to utilize the far side of the moon for some seriuos astronomy! Am I rite?

• by SmokeGS on 5/28/19, 9:14 PM

  Billboards from LEO. I'm not a fan but it could monetize key tech for space travel.

• by perilunar on 5/29/19, 12:29 AM

  This is such an incredibly short-sighted view from astronomers. The same tech that is going to enable SpaceX to launch thousands of satellites is exactly what will enable (and fund) the expansion of humans into space — which will be more of a boon to astronomy in the long term than any number of large ground-based telescopes.

  I'm perfectly happy to permanently screw over ground-based astronomy if that's what it take to get us into space.

  Just build the damn telescopes in space. And stop thinking single-mirror scopes like Hubble — you could build huge multiple-segment mirrors in space — much bigger than anything on earth.