Announcement

Collapse
No announcement yet.

Blue MAGnitude ?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Blue MAGnitude ?

    Stars - One of the earliest applications of color was simply looking at the blue light versus the green light from stars. Early in this century, little was known about stars, and particularly, no one knew why some stars looked red, others white, others yellow, others bluish. In fact, many scientists of the day guessed that the color was an evolutionary sequence, that the bluest stars were the youngest and slowly cooled into old, red stars. One of the first systematic attempts to measure the color of stars was carried out independently by Hertzsprung (in 1911) and Russell (in 1913). In what now seems like an obvious to make, these astronomers were the first to plot the brightness of stars (Green magnitude) vs. their colors (Blue magnitude - Green magnitude). In doing so, they very quickly discovered that nearly all stars inhabit two sequences on that plot. They called the larger sequence the Main Sequence and the smaller one the Giant Sequence ("giant" because these stars are much brighter). Here is a modern H-R diagram, Hipparcos (redder is toward the right; brighter is toward the top), where both sequences can be seen clearly. The scientific value of this diagram is hard to overstate. Astronomers evaluating this diagram rapidly began to understand that the stars didn't evolve from the blue end to the red end of the main sequence. Rather, the colors were a sequence in stellar mass, with more massive stars being brighter and bluer and smaller stars redder and fainter. Later, we came to understand that the giant sequence is an evolutionary feature, a final blaze of glory that all stars go through. The principle thrust of astrophysics for the next 50 years was understanding just how stars formed and evolved along this diagram.

  • #2
    pu12e always the philosapher?...philosaphor ?...philosafur?...um.......
    phillip-officer.......hmmmm back to grade school for damo

    Comment


    • #3
      Originally posted by Da Main Man
      pu12e always the philosapher?...philosaphor ?...philosafur?...um.......
      phillip-officer.......hmmmm back to grade school for damo
      I think this part is all a conspiracy:

      They called the larger sequence the Main Sequence and the smaller one the Giant Sequence ("giant" because these stars are much brighter).
      I bet some virtual entity wrote this shit.. while on meth and juice.

      Comment

      Working...
      X