2000
August 11: These are the first spectra via
the larger Starlight Xpress MX9 CCD camera and confined to the red end
of the spectrum. Resolution is slightly lower than via the MX5 and
HX5 cameras but twice as much of the spectrum can be captured in a single
image. These include the first WPO spectrograms to clearly show H
a
in d Sco
despite its exceptionally low altitude - a star that seems to be entering
a g Cas
phase according to reports. P
Cyg and b
Lyr
also show He in emission - the latter [at this stage in its cycle] as twin
emission lines for both Ha
and He. More
associated spectra.
The B and a bands are caused by water-vapour and oxygen in the Earth's atmosphere superimposed on all spectra and act [in the absence of a slit to apply a reference source] as static markers.
