Interactive ORFEUS Echelle Image

Notes on spectra

The following features are visible in some of the spectra, which are either artifacts or not part of the stellar spectrum:

• Testpulse peak: Some spectra show a peak at 1317 Å in order 42, which is due to a not completely removed testpulse peak of the echelle electronics.
• Airglow and geocorona:
  • Airglow: OI lines at 1302, 1305 and 1306 Å, also at 989 Å
  • Geocorona: Ly-alpha (very strong) at 1216 Å, Ly-beta at 1026 Å

Note: The above java tool was written by Jürgen Barnstedt from the ORFEUS Group at Tübingen and is used by MAST with his permission.