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Honestly I hope someone figures out how to shoot these down. I feel like the planet isn't getting a say. In fact only a few people are getting a say that this n

Honestly I hope someone figures out how to shoot these down. I feel like the planet isn't getting a say. In fact only a few people are getting a say that this network should even exist. Astronomy is dead. A dark sky with just stars, yeah dead.

deleted 7y ago
[deleted]
dwaltrip 7y ago
Aren't the satellites in LEO only visible for a short time after sunset?
- raattgift 7y ago
  This landed earlier today. https://arxiv.org/abs/2001.10952 https://arxiv.org/abs/2001.10952 tl;dr: starlink and its competitors pose serious Earth-based observation problems across the spectrum (§§4.1-4.2) especially for faint variable objects which require long exposures and for which any missed pixels matter. The missed-pixels problems run around the clock, not just when the sattelites are visibly flaring, as do non-visible-spectrum noise problems.
  - themeiguoren 7y ago
    From a first-principles perspective, it's baffling to me why this would ever be a serious problem. We know the ephemerides of all objects in Earth orbit, and they are traveling at a fast enough angular speed to not linger in an observational spot. We're not working with long-exposure film here - we can manipulate pixels over time. On a technical level it should be trivial to mask out the pixels where satellites are located at each moment. I think 1% is far too high a guesstimate, but say that artificial satellites end up covering 1% of the full night sky (for context the moon takes up under 0.001% of the sky's area). That still leaves you with 99% observability - hardly an effect on the amount of data you can bring in, especially compared to such problems as clouds. Dead-simple algorithms to erase satellite trails are available for hobbyists right now: https://www.skyandtelescope.com/astronomy-blogs/imaging-foundations-richard-wright/satellites-begone-how-to-remove-satellite-trails-from-your-astrophotography/ https://www.skyandtelescope.com/astronomy-blogs/imaging-foun... And more complex ones for professional astronomers should still be super simple to implement compared to many of the algorithms astronomers have to wrangle with.
    - raattgift 7y ago
      We don't want to manipulate pixels; the goal is not to produce pretty pictures of known things. The goal is to collect as much data as possible about things which are not well understood (because, in part, of a lack of data), especially those that are time-varying on short human timescales. The objects in question are often extremely faint, and even if one knows a lot of the details of periodic noise, removing the noise does not recover the faint signal. > baffling Stand by, there will be lot of professional science communication on this topic in due course. > moon, 1%, ... Suppose right now at the very limb of the sun we detect an extremely interesting light curve that is clearly not extragalactic yet still atypical of supernovae, but know that it is in the process of moving directly behind the sun (from our perspective). How do you propose to remove the sun from the image of the suspected supernova? Here's a list of solar-system objects that moved directly behind the sun in 2019: https://sungrazer.nrl.navy.mil/index.php?p=transits/transits_2019 https://sungrazer.nrl.navy.mil/index.php?p=transits/transits... This Christmas would have been an interesting time for 2010: The Year We Make Contact's great black spot of Jupiter to appear. The moon also occults Jupiter fairly regularly. If Jupiter was doing something strange behind the moon, think of the loss for all the Earth-based observatories. Or would it be trivial for them to faithfully reconstruct the unusual behaviour of Jupiter? Yes, the sun and moon are slow-moving, bright, and high-solid-angle obstructions compared to any spacecraft. However, so is Jupiter and a galactic supernova, and neither of them are usually interestingly variable on the scale of a glitching millisecond pulsar (for example) or the electromagnetic counterparts to a gravitational wave detection. In short > algorithms to erase satellite trails are doing cosmetics, not astronomical or astrophysical research. And if cosmetically you erase the wrong pixel, you miss out lots of observation time of events like https://en.wikipedia.org/wiki/ASASSN-15lh#Discovery https://en.wikipedia.org/wiki/ASASSN-15lh#Discovery and end up regretting missing early data (as in e.g. SN 1997D). http://www.astronomy.ohio-state.edu/asassn/index.shtml http://www.astronomy.ohio-state.edu/asassn/index.shtml exists to avoid missing out on such things again, and if you have a thick skin, there's https://twitter.com/SuperASASSN https://twitter.com/SuperASASSN A recent tweet is interesting: 'This is, by the way, a discovery made in "astronomical twilight" - one way Itagaki and other amateur astronomers can discovered such events before professional astronomers is by observing fields (galaxies) quite close to the Sun.' (although that's in large part because bigger observatories deliberately aim away from the sun, because it's very noisy and its luminosity may damage sensitive detectors).
- coding123 7y ago
  Even if astronomy isn't affected. Can you imagine a grid/net of fast moving satellites, 80,000 satellites covering the entire globe that are visible for 2 to 3 hours every night. This is the thing that creates global suicides. Mark those words. It will happen.
  - coding123 7y ago
    Sorry this is worth more commenting - I am just imagining this network above us. Every centimeter to an inch "visually" a grid pattern crossing over us for a period of 2 hours a night. No, a website that tells you when it's coming, ooooh... No this is every single night, and morning, a grid from HELL. I'm a fairly regular poster, a software engineer, decently intelligent guy - and this future absolutely disgusts me. I hope things change and it ends up not happening. I would rather telephone pole the world.
    - ddalex 7y ago
      [DELETED because dups and all that; I guess I got over excited :) ]
  - nickik 7y ago
    You will at most see 2-3 satellites from the whole Starlink constalation and only if you take a lot of care where you look and when. Most people will never even notice those satellites.
    - loriverkutya 7y ago
      Not really true: "For his analysis, he factored in the first leg of SpaceX’s Starlink constellation — about 1,600 satellites — as there are better details about the orbits they’re going to. Based on just that initial batch, he estimated that at a latitude of 52 degrees north (about where London is located), there will be 84 Starlink satellites above the horizon at all times. And for many hours around dusk, dawn, and in the nighttime during summer, 15 of those satellites would be visible in the sky at all times, about 30 degrees above the horizon." From here: https://www.theverge.com/2019/5/29/18642577/spacex-starlink-satellite-constellation-astronomy-light-pollution https://www.theverge.com/2019/5/29/18642577/spacex-starlink-...
jayd16 7y ago
I really can't fathom the reasoning behind this much passion about astronomy tied to this much hatred of putting things in space.
- carlivar 7y ago
  Because you're thinking of "space" as just boring orbital stuff. Astronomers think of our solar system, deep space, distant stars... a bunch of gadgets blocking the view of that is a legitimate concern.
  - neurostimulant 7y ago
    It's not like the constellation move in unpredictable manner. The orbits are known, the movements are predictable, surely with some processing it shouldn't affect astronomy too much? If astronomers can overcome random atmospheric dispersion, surely they can elimitate starlink from post-processed images too?
- aylmao 7y ago
  I agree with the sentiment of the parent comment. Not because I have a huge passion for astronomy, but because I think we're prioritizing things in a wrong way. We're prioritizing yet another billionare's networking business over the capacity to study our night's sky. Much like other types of pollution, this is something that could stick around for hundreds of years, even after all its utility is gone. Cell towers, like most structures, can be brought down, repurposed, updated and altered. We can't do nothing about satellites, and don't know how to clean space pollution.
  - modeless 7y ago
    Firstly, the satellites fall out of orbit automatically within 5 years even if they break because they're in LEO. Secondly, again because they're in LEO they are invisible for most of the night while they are in Earth's shadow, not affecting stargazing or astronomy in the slightest during that time. It's only an hour or so near dawn and dusk where the satellites are visible.
Dylan16807 7y ago
Ground-based light pollution is a far, far bigger problem than low orbit satellites.
- coding123 7y ago
  That also depends specifically where you are. If you move out to Rural New Mexico, this is a goddamn nightmare.
rkangel 7y ago
Maybe the historical form of amateur astronomy with a telescope in the garden might die out (others have made some reasonable counter-arguments). But maybe instead, space based astronomy will become cheaper and more accessible due to the drop in launch costs? My understanding is that a lot of astronomy research (as distinct from amateur stargazing) is limited by atmospheric concerns, so maybe that would be an improvement.

deleted 7y ago

[deleted]

dwaltrip 7y ago

Aren't the satellites in LEO only visible for a short time after sunset?

raattgift 7y ago
This landed earlier today. https://arxiv.org/abs/2001.10952 https://arxiv.org/abs/2001.10952 tl;dr: starlink and its competitors pose serious Earth-based observation problems across the spectrum (§§4.1-4.2) especially for faint variable objects which require long exposures and for which any missed pixels matter. The missed-pixels problems run around the clock, not just when the sattelites are visibly flaring, as do non-visible-spectrum noise problems.
- themeiguoren 7y ago
  From a first-principles perspective, it's baffling to me why this would ever be a serious problem. We know the ephemerides of all objects in Earth orbit, and they are traveling at a fast enough angular speed to not linger in an observational spot. We're not working with long-exposure film here - we can manipulate pixels over time. On a technical level it should be trivial to mask out the pixels where satellites are located at each moment. I think 1% is far too high a guesstimate, but say that artificial satellites end up covering 1% of the full night sky (for context the moon takes up under 0.001% of the sky's area). That still leaves you with 99% observability - hardly an effect on the amount of data you can bring in, especially compared to such problems as clouds. Dead-simple algorithms to erase satellite trails are available for hobbyists right now: https://www.skyandtelescope.com/astronomy-blogs/imaging-foundations-richard-wright/satellites-begone-how-to-remove-satellite-trails-from-your-astrophotography/ https://www.skyandtelescope.com/astronomy-blogs/imaging-foun... And more complex ones for professional astronomers should still be super simple to implement compared to many of the algorithms astronomers have to wrangle with.
  - raattgift 7y ago
    We don't want to manipulate pixels; the goal is not to produce pretty pictures of known things. The goal is to collect as much data as possible about things which are not well understood (because, in part, of a lack of data), especially those that are time-varying on short human timescales. The objects in question are often extremely faint, and even if one knows a lot of the details of periodic noise, removing the noise does not recover the faint signal. > baffling Stand by, there will be lot of professional science communication on this topic in due course. > moon, 1%, ... Suppose right now at the very limb of the sun we detect an extremely interesting light curve that is clearly not extragalactic yet still atypical of supernovae, but know that it is in the process of moving directly behind the sun (from our perspective). How do you propose to remove the sun from the image of the suspected supernova? Here's a list of solar-system objects that moved directly behind the sun in 2019: https://sungrazer.nrl.navy.mil/index.php?p=transits/transits_2019 https://sungrazer.nrl.navy.mil/index.php?p=transits/transits... This Christmas would have been an interesting time for 2010: The Year We Make Contact's great black spot of Jupiter to appear. The moon also occults Jupiter fairly regularly. If Jupiter was doing something strange behind the moon, think of the loss for all the Earth-based observatories. Or would it be trivial for them to faithfully reconstruct the unusual behaviour of Jupiter? Yes, the sun and moon are slow-moving, bright, and high-solid-angle obstructions compared to any spacecraft. However, so is Jupiter and a galactic supernova, and neither of them are usually interestingly variable on the scale of a glitching millisecond pulsar (for example) or the electromagnetic counterparts to a gravitational wave detection. In short > algorithms to erase satellite trails are doing cosmetics, not astronomical or astrophysical research. And if cosmetically you erase the wrong pixel, you miss out lots of observation time of events like https://en.wikipedia.org/wiki/ASASSN-15lh#Discovery https://en.wikipedia.org/wiki/ASASSN-15lh#Discovery and end up regretting missing early data (as in e.g. SN 1997D). http://www.astronomy.ohio-state.edu/asassn/index.shtml http://www.astronomy.ohio-state.edu/asassn/index.shtml exists to avoid missing out on such things again, and if you have a thick skin, there's https://twitter.com/SuperASASSN https://twitter.com/SuperASASSN A recent tweet is interesting: 'This is, by the way, a discovery made in "astronomical twilight" - one way Itagaki and other amateur astronomers can discovered such events before professional astronomers is by observing fields (galaxies) quite close to the Sun.' (although that's in large part because bigger observatories deliberately aim away from the sun, because it's very noisy and its luminosity may damage sensitive detectors).
coding123 7y ago
Even if astronomy isn't affected. Can you imagine a grid/net of fast moving satellites, 80,000 satellites covering the entire globe that are visible for 2 to 3 hours every night. This is the thing that creates global suicides. Mark those words. It will happen.
- coding123 7y ago
  Sorry this is worth more commenting - I am just imagining this network above us. Every centimeter to an inch "visually" a grid pattern crossing over us for a period of 2 hours a night. No, a website that tells you when it's coming, ooooh... No this is every single night, and morning, a grid from HELL. I'm a fairly regular poster, a software engineer, decently intelligent guy - and this future absolutely disgusts me. I hope things change and it ends up not happening. I would rather telephone pole the world.
  - ddalex 7y ago
    [DELETED because dups and all that; I guess I got over excited :) ]
- nickik 7y ago
  You will at most see 2-3 satellites from the whole Starlink constalation and only if you take a lot of care where you look and when. Most people will never even notice those satellites.
  - loriverkutya 7y ago
    Not really true: "For his analysis, he factored in the first leg of SpaceX’s Starlink constellation — about 1,600 satellites — as there are better details about the orbits they’re going to. Based on just that initial batch, he estimated that at a latitude of 52 degrees north (about where London is located), there will be 84 Starlink satellites above the horizon at all times. And for many hours around dusk, dawn, and in the nighttime during summer, 15 of those satellites would be visible in the sky at all times, about 30 degrees above the horizon." From here: https://www.theverge.com/2019/5/29/18642577/spacex-starlink-satellite-constellation-astronomy-light-pollution https://www.theverge.com/2019/5/29/18642577/spacex-starlink-...

jayd16 7y ago

I really can't fathom the reasoning behind this much passion about astronomy tied to this much hatred of putting things in space.

carlivar 7y ago
Because you're thinking of "space" as just boring orbital stuff. Astronomers think of our solar system, deep space, distant stars... a bunch of gadgets blocking the view of that is a legitimate concern.
- neurostimulant 7y ago
  It's not like the constellation move in unpredictable manner. The orbits are known, the movements are predictable, surely with some processing it shouldn't affect astronomy too much? If astronomers can overcome random atmospheric dispersion, surely they can elimitate starlink from post-processed images too?
aylmao 7y ago
I agree with the sentiment of the parent comment. Not because I have a huge passion for astronomy, but because I think we're prioritizing things in a wrong way. We're prioritizing yet another billionare's networking business over the capacity to study our night's sky. Much like other types of pollution, this is something that could stick around for hundreds of years, even after all its utility is gone. Cell towers, like most structures, can be brought down, repurposed, updated and altered. We can't do nothing about satellites, and don't know how to clean space pollution.
- modeless 7y ago
  Firstly, the satellites fall out of orbit automatically within 5 years even if they break because they're in LEO. Secondly, again because they're in LEO they are invisible for most of the night while they are in Earth's shadow, not affecting stargazing or astronomy in the slightest during that time. It's only an hour or so near dawn and dusk where the satellites are visible.

Dylan16807 7y ago

Ground-based light pollution is a far, far bigger problem than low orbit satellites.

coding123 7y ago
That also depends specifically where you are. If you move out to Rural New Mexico, this is a goddamn nightmare.

rkangel 7y ago

Maybe the historical form of amateur astronomy with a telescope in the garden might die out (others have made some reasonable counter-arguments). But maybe instead, space based astronomy will become cheaper and more accessible due to the drop in launch costs? My understanding is that a lot of astronomy research (as distinct from amateur stargazing) is limited by atmospheric concerns, so maybe that would be an improvement.