The following is a list of the 'unknown' spectrum
plots in this directory.
The header of an 'unknown' plot will give a name for that star and
date of observation.
In some cases the 'unknown' is also on the
standards list, but a night different than the standards spectrum,
and with an alternate name for the star.
The K stars among these will be harder to classify than the others
because of the shortage of K and late G standards.
AMMT Abt Meinel Morgan Tapscott An Atlas of Low Dispersion Grating Stellar
C+J Cowley & Jaschek AJ 74, 375 1969
GGv69 Gray & Garrison ApJSup 69, 301
GGv70 Gray & Garrison ApJSup 70, 626
KM Keenan & McNeil An Atlas of Spectra of the Cooler Stars
KM2 Keenan & McNeil ApJSup 71, 245 1989
KY Keenan & Yorka BICDS 29, 25 1985
L Lesh ApJSupp 17, 371
MAT Morgan Abt Tapscott Revised MK Spectral Atlas for Stars Earlier than
W Walborn ApJSupp 23, 257
Y Yamashita, Nariai, Norimoto An Atlas of Representative Stellar Spectra
Some spectra with ID to show more examples of spectrum quality, or for classroom classification practice; and
some spectra without ID given.
Xi2Cet B9III C+J This is a spectroscopic binary.
HR21 = HD432 = Beta Cas F2III-IV MAT standard.
A different night than the standards plot
Beta Ari A5V This is a spectroscopic binary.
Eta Hya B3V is the general consensus, but L likes B4V
HR4295 = HD95418 = Beta UMa A1V A different
observation of the standard star.
Could use it as an unknown, or to
see what the noise level is in a typical well observed spectrum of a bright star.
Gamma Boo A7III is the usual classification; AJ 121, 2148 says A7IV+(n),
making a careful subtle distinction between IV & III.
HR5062 = 80UMa F1V standard, A different observation than the
HD149757 = Zeta Oph O9.5V
HD204827 O9.5V Weaver & Torres-Dodgen ApJ 487,847 1997
Others have called it B0V
Note that this star is relatively faint (8.00 V, 8.69 B),
so the spectrm is noisy,
and reddened, so the spectrum is
flatter than the standards of the same spectral type.
Zeta Peg B8V
2 And A3Vn C+J
The following spectra are noisier than those above; the stars are faint:
HD25992 about K0III; the photographic spectra used to determine
this are lower dispersion than usual, so this type is less
certain than the others here
HD100340 The HD spectral type given on SIMBAD is way off
LSI+61 325 This star is so faint that it was
observed at WIYN, not PBO; Significant reddening
BD +62 657 Significant reddening
Anonymous: Spectra without ID in the header, for classroom use.
The following are real unknowns: the readout of the telescope pointing
become inaccurate; when that happens the star observed
is sometimes not the star intended,
and which star was actually observed
cannot be definitely determined (though there
can be a strong suspicion
of what it was). Some of these are fairly noisy spectra
(the observed star was fainter than the target star, for which the
exposure time was set).
unknown5 040208 probably 4 Canis Minoris
unknown6 001104 probably HD4142