alt Hacker NewsThe year is 2026. Surely the orbits of all the satellites are known well enough, and optics are modelled well enough for telescopes to know which few pixels to ignore at any given moment?
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jfim • today at 5:32 AM
Light scatters in the atmosphere, it's the same reason you can shine a laser beam and see it even though the light should be collimated. With enough sources of light, you end up with more background light pollution.
There's at least two issues with this line of thinking:
1. many astronomical observations are long integrations (many minutes of open shutter) and you often cannot read out the pixels during the exposure. So you can't selectively ignore pixels on a "by moment" basis. And with enough satellites, enough pixels could be affected to render an entire image effectively unusable
2. It seems you're thinking only about optical astronomy. There's also a ton of radio/millimeter wave astronomy that's done from the ground. Satellites have radio-wave downlinks that can be powerful enough to destroy the electronics used in radio astronomy receivers. The US's National Radio Astronomy Observatory has been working on data sharing with Starlink to mitigate this, but it's basically up to companies to agree to work together. Other satellites / companies don't engage in this coordination and so some radio telescopes need to go to a "safe"/stow position to protect the electronics. This costs valuable observing time.