Comment on Seconds

m0darn@lemmy.ca ⁨2⁩ ⁨weeks⁩ ago

• Generous1146@beehaw.org ⁨2⁩ ⁨weeks⁩ ago

  What even is color if not seconds^-1?

  source

  • m0darn@lemmy.ca ⁨2⁩ ⁨weeks⁩ ago

    Yeah true, but I think they actually use wavelength of red shift, which is distance… traveled by light in the time it takes to make a full cycle. So I guess we’re back to seconds again.

    I think they use this for distance and time because at scales being dealt with they have the same implications.

    source
• Allero@lemmy.today ⁨2⁩ ⁨weeks⁩ ago

  They normally use parallax-seconds, i.e. parsecs, for long distance objects.

  source

  • m0darn@lemmy.ca ⁨2⁩ ⁨weeks⁩ ago

    I think you need to be more specific than ‘long distance’, yes they use parsecs for ‘long distances’ but I believe only for intra-galactic objects. I think other galaxies are too distant for parallax seconds to be useful.

    source

    • Allero@lemmy.today ⁨2⁩ ⁨weeks⁩ ago

      Fair!

      Thanks for this bit of clarification

      source