Inner Voice (inner_v0ice) wrote in little_details,
Inner Voice

Emergence of the idea that the starlight we see is years old

When did astronomers first formulate the theory that, because of the distance it has to travel, the starlight we see is years old? (And therefore that a star that we can see "now" could have died years ago without our knowing?)

Wiki'd: "speed of light", "lightyear", "parallax"

Found out:
- people have been trying to measure the speed of light since the 1600s, and succeeding to some degree (Rømer and Huygens, 26% off the present value, ~1676) - but the references are all to bodies within the solar system (Jupiter and its moons; the Sun)
- people have been trying to measure the distance to stars since the 1700s, and succeeding since the 1800s (Bessel, 1838)

Should I just assume that, given this data, any intelligent astronomer from the 1700s onward would have just automatically put together these two ideas and said "hey, we know that light travels at a finite speed and we're trying to calculate how far away the stars are; obviously the light we're seeing from the stars is delayed, in some cases by years"? Or was there any one guy that this idea officially originates from?

(edited to add: setting is sci-fi future--specifically, it's a throwaway line for Mr. Spock)

(edited again to add: found a good lead; a 1905 article from the Urbana Daily Courier explaining the concept to the general public here.)
Tags: ~science: astronomy
  • Post a new comment


    default userpic
    When you submit the form an invisible reCAPTCHA check will be performed.
    You must follow the Privacy Policy and Google Terms of use.