One of the benefits of doing astronomy in late December at this latitude (48 N) is that one can begin observing at 5:00 pm, wrap things up by 9:00 pm and still have an early bedtime. the following observations were made on December 20 and 23, 2023.
Class
Spectral
Type
Name(s)
Obs Date
Time
profile /
reference
O
O9V
10 Lac
HIP_111841
HD214680
12/20/23
5:25 pm
B
B0.5IIIs
Alfirk
bet Cep
HIP_106032
HD205021
12/23/23
7:11 pm
B
B8III
87 Psc
HD7374
HIP_5778
12/23/23
6:10 pm
A
A1IV_sh
HIP_62572
HD112028
12/23/23
6:37 pm
A
A7III
28 And
HD2628
HIP_2355
12/23/23
5:14 pm
Obviously, the best match was for the star Alfirk. I cannot explain the deviations for the other profiles. All profiles were created with the same master flat frame; all used the same instrument response, and all were taken within an hour on the same evening except 10 Lacerta three days earlier.
In addition to trying to improve my workflow, I want to take a look at rectified profiles for these observations (by dividing out the continuum) so I can more readily compare my results with those in Walker’s Atlas. I will save that for another post.