W. A. Feibelman, Goddard Space Flight Center, reports that image-tube spectrograms (range 3700-7300 A, dispersions 82 and 41 A/mm) taken on Apr. 29, 30 and May 8 by A. Mallama and L. Brown with the 91-cm reflector show several changes in the emission-line spectrum of HM Sge relative to spectrograms taken on 1978 Apr. 15 by R. Hobbs. Microdensitometer tracings show that the [Ne III] 3868 A line is now about three times as strong as H-beta 3889 A, the [O III] 4363 A line is now stronger than H-gamma 4340 A, the [O III] 5007 A line is now considerably stronger than H-beta 4861 A, and the broad Woif-Rayet feature at 4650-4700 A is now weaker than it was a year ago.
International Astronomical Union Circular
- Pub Date:
- May 1979