Chemical Composition of M8 Based on IUE and Visual Observations

Abstract

We present optical and IUE observations of the Hourglass Nebula which is embedded in the galactic H II region M8. By comparing the intensities of the [C III] lines λλ1907 + 1909 with that of C II λ4267, a value of t² = 0.046±0.01 is obtained. The logarithmic abundances by number of the gaseous component for t² = 0.046 are: H = 12.00, He = 11.00 C = 8.55, N = 7.80, 0 = 8.74, Ne = 7.99, S = 7.38, Ar = 6.76, and Fe = 6.16. These abundances are compared with those of other galactic H II regions, the Sun, and B stars of the solar neighborhood.