Recent content by ladybug1829

  1. L

    Calculate the line of sight velocity dispersion of the cluster in km/sec

    1".3arc = (1.3/3600) degrees = (1.3/3600) X (TT / 180) Radians = 6.302577854 X 10^-6 Radians = proper motion / distance. => distance = proper motion / 6.302577854 X 10^-6 Radians = 158,665.2356 X proper motion. Derive the rms value of the five (divide by 5 to get mean square) that gives...
  2. L

    Calculate the line of sight velocity dispersion of the cluster in km/sec

    Thanks :) Anyone else know the second part?
  3. L

    Calculate the line of sight velocity dispersion of the cluster in km/sec

    Please Help :) "Calcium H and K lines have rest frame wavelengths of 3968.5 A (angstrom). Spectroscopy of 5 stars in a cluster revealed that the Ca H line was detected at 3970.1 A 3966.3 A 3967.5 A 3971.0 A 3968.2 A in each of these five stars. Calculate the line of sight velocity dispersion of...