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Exposures are generally taken frequently enough that any that would be problematic for data can simply be dropped. The satellites aren't permanently positioned

Exposures are generally taken frequently enough that any that would be problematic for data can simply be dropped. The satellites aren't permanently positioned in the sky. Geostationary satellites permanently lose any data behind them (although I haven't heard of a geostationary satellite being positioned precisely problematically).

irthomasthomas 6y ago
Searching for exoplanets moving in front of a star, involves measuring the luminosity of a single pixel for ~1% change. Dropping frames ruined by a satellite train isn't going to work. E.g https://www.sciencealert.com/a-bunch-of-potential-tabby-s-star-alikes-have-just-been-identified https://www.sciencealert.com/a-bunch-of-potential-tabby-s-st...
- nsilvestri 6y ago
  You absolutely can drop those frames. Exoplanetary transits are generally in the range of 1 to 4 hours, and hundreds of exposures may be taken in that time. In my undergraduate I studied astronomy and some of my classmates did an exoplanet detection project with a 61" scope and had issues with satellites on a handful of frames. Sure, it sucks to lose 2 minutes worth of data, but it's not even lose to catastrophic when you have the data before and after as well.
- CamperBob2 6y ago
  Absolute bunk. As numerous people have tried to explain in this thread (along with its frequent predecessors), anything that moves across frames is by definition unimportant when stacking images. It's literally the difference between integration and differentiation. Satellites move fast. Not only that, but you know exactly where and when they will cross your field of view, and for how long they'll remain within it. If the astronomy community can't muster the rudimentary image processing technology needed to reject satellites and other transient objects, I'm not exactly confident in their ability to finally figure out the whole origin-of-the-Universe thing.
  - ViViDboarder 6y ago
    So if someone decides to make money with a byproduct being messing with your day job, you’d just shrug it off?
    - CamperBob2 6y ago
      If I were that incompetent at my day job, I imagine quite a few people would be "messing" with me, possibly for the sheer amusement of it.
      - salawat 6y ago
        Suppose your job comes and goes with the whims of a grant or funding committee, so every last dollar you spend having to compensate for some other guy's scheme. Science is not just difficult because the research being done is hard; it's also difficult because everything you're trying to do is being done in spite of the fact 95% of the rest of the world could give a care leas that you're doing, so that last 5% of support you can count has to go a long way. I can understand the bitterness perfectly, and to be frank, your response is exactly the reason they deserve to be irate.
        CamperBob2 6y ago
        So why should a goal like truly universal Internet access play second fiddle to astronomical considerations, when the technical solutions required for coexistence are so trivial? (And I really couldn't care less how many astronomers disagree with the assertion that it's trivial to avoid interference to observations from satellite passes. If I want to know something about astronomy, I'll ask an astronomer. Astronomers, by the same token, should consult digital imaging experts before concluding that the rest of the world is out to wreck their careers with unreasonably-expensive or technically-insurmountable roadblocks. You guys can afford to lose a frame or two now and then in exchange for what Starlink offers the rest of humanity.)

irthomasthomas 6y ago

Searching for exoplanets moving in front of a star, involves measuring the luminosity of a single pixel for ~1% change. Dropping frames ruined by a satellite train isn't going to work. E.g https://www.sciencealert.com/a-bunch-of-potential-tabby-s-star-alikes-have-just-been-identified https://www.sciencealert.com/a-bunch-of-potential-tabby-s-st...

nsilvestri 6y ago
You absolutely can drop those frames. Exoplanetary transits are generally in the range of 1 to 4 hours, and hundreds of exposures may be taken in that time. In my undergraduate I studied astronomy and some of my classmates did an exoplanet detection project with a 61" scope and had issues with satellites on a handful of frames. Sure, it sucks to lose 2 minutes worth of data, but it's not even lose to catastrophic when you have the data before and after as well.
CamperBob2 6y ago
Absolute bunk. As numerous people have tried to explain in this thread (along with its frequent predecessors), anything that moves across frames is by definition unimportant when stacking images. It's literally the difference between integration and differentiation. Satellites move fast. Not only that, but you know exactly where and when they will cross your field of view, and for how long they'll remain within it. If the astronomy community can't muster the rudimentary image processing technology needed to reject satellites and other transient objects, I'm not exactly confident in their ability to finally figure out the whole origin-of-the-Universe thing.
- ViViDboarder 6y ago
  So if someone decides to make money with a byproduct being messing with your day job, you’d just shrug it off?
  - CamperBob2 6y ago
    If I were that incompetent at my day job, I imagine quite a few people would be "messing" with me, possibly for the sheer amusement of it.
    - salawat 6y ago
      Suppose your job comes and goes with the whims of a grant or funding committee, so every last dollar you spend having to compensate for some other guy's scheme. Science is not just difficult because the research being done is hard; it's also difficult because everything you're trying to do is being done in spite of the fact 95% of the rest of the world could give a care leas that you're doing, so that last 5% of support you can count has to go a long way. I can understand the bitterness perfectly, and to be frank, your response is exactly the reason they deserve to be irate.
      - CamperBob2 6y ago
        So why should a goal like truly universal Internet access play second fiddle to astronomical considerations, when the technical solutions required for coexistence are so trivial? (And I really couldn't care less how many astronomers disagree with the assertion that it's trivial to avoid interference to observations from satellite passes. If I want to know something about astronomy, I'll ask an astronomer. Astronomers, by the same token, should consult digital imaging experts before concluding that the rest of the world is out to wreck their careers with unreasonably-expensive or technically-insurmountable roadblocks. You guys can afford to lose a frame or two now and then in exchange for what Starlink offers the rest of humanity.)