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Unless they were painted with VentaBlack? [1] https://en.wikipedia.org/wiki/Vantablack https://en.wikipedia.org/wiki/Vantablack

• Dylan16807 9y ago
  I wasn't aware that let stars shine through solid objects.
  • psadri 9y ago
    “If something looks interesting enough, one of the telescopes is switched to laser mode, and a laser flash is used to illuminate the target. Even black objects reflect some light.” I was referring to this part.
    • Dylan16807 9y ago
      That wasn't the part about finding satellites, though. And 99.965% absorption is still visible in a bright light.
      • Zak 9y ago
        There's an interesting demonstration of this on Youtube: "The Worlds Blackest Black vs The Worlds Brightest Flashlight (32,000 lumen)—Which Will Win?" https://www.youtube.com/watch?v=AaFdCvnV8PM https://www.youtube.com/watch?v=AaFdCvnV8PM To summarize, the flashlight wins, and it's reasonable to expect the effect would be the same with a laser and sensitive detection equipment.
      • detritus 9y ago
        @zak (sorry, I couldn't reply directly) That isn't Vantablack as such though, is it? Afaik, Vantablack proper requires a specific application process [1], which I've mentally envisaged as being something akin to growing diamonds in a lab on a substrate, or applying flocking to materials. I'd be quite curious to know what the reflectivity would be like on some clever coating consisting of vertically-laid carbon nano tubes, etc. [1] - https://www.surreynanosystems.com/vantablack/applying-vantablack https://www.surreynanosystems.com/vantablack/applying-vantab...
  • s0rce 9y ago
    Have to use a negative index of refraction metamaterial cloak