December 1967 Potassium Flares "HD 117,043 is a rather ordinary dwarf star of spectral type
Tauri star RY Tau, the spatial distribution of early spectral type
magnetic stars, the effect of high excitement level on the hydrogen ionization and recombination rates, detecting low-amplitude photometric variability in magnetic white dwarfs, and prototyping a moderate-resolution holographic spectrograph.
A solar twin should have a temperature, mass, and spectral type
similar to our Sun.
Furthermore, during this period of less than three minutes the star underwent an abrupt change from spectral type
M to B; in other words, it went from a temperature of 2,800 kelvin (K) to six or seven times more than that," he stated.
315 derived from 2MASS (see remarks about Table 2, above) indicate a blended spectral type
of around F2 and temperature ~7000 K.
005 Program star details STAR UV Grus SPECTRAL TYPE
N/A RA Dec GSC 2MASS SV (2000) (2000) B 22 19 53.
I picked these based on the experience of other astronomers and knowledge of the variability with stellar spectral type
However, as noted by Koen, its reported spectral type
A2 is late for a SPB.
The second half of the report deals with the progress that has already been made towards the resolution of the problem of calibration, particularly the studies aimed at obtaining an initial list of normal stars with reliable spectral type
and good visible photometry and that have a high density on the sky.
The June-July 2016 conference in Prague continued the study of stars with spectral type
B and forbidden emission lines in its spectrum--B[e] stars--and related phenomena.
This term generally refers to dwarf stars with a spectral type
ranging from K5V to M5V.
Its spectral type
is a run-of-the-mill M1 or M2, but we see its light severely reddened--and dimmed about 2 magnitudes--by both circumstellar and interstellar dust.