Here are the 15 brightest stars in the constellation in descending order of magnitude: the HD numbers are he numbers in the Henry Draper Catalogue, the first serious attempt to record the spectral class of all the stars listed in a major star catalogue.
Name Designation Magnitude Distance (ly) Spectral class
γ Sge HD189319 3.51 274 ly K5 III
δ Sge A HD187076 3.68 448 ly M2 II
δ Sge B HD187077 3.80 448 ly B6
α Sge HD185758 4.39 473 ly G0 II
β Sge HD185958 4.39 466 ly G8 II
ζ Sge HD187362 5.01 326 ly A3 V
η Sge HD190608 5.09 162 ly K2 III
13 Sge HD189577 5.33 746 ly M4 IIIa
11 Sge HD189090 5.54 404 ly B9 III
1 Sge HD180317 5.65 318 ly A4 V
ε Sge HD185194 5.67 473 ly G8 IIIvar
S Sge HD188727 5.71 4289 ly G5Ibv
15 Sge HD190406 5.80 58 ly G1V binary star
HD193579 5.82 477 ly K5 III
HD190211 5.99 849 ly K3 Iab
I stopped at Magnitde 6, the limit of naked eye visibility but obviously there are far many more stars below magnitude 6 than above it. The frst link carries on down to magnitude 6.84, with a further 14 stars listed.
To understand the spectral classes quoted you need to read about the Morgan-Keenan spectral classes of stars (see link).
Blue stars are the hottest and in class O and B. Then come classes A, F. and G (our Sun is in Class G) which are white and yellow, followed by K (orange) and M (red).
Size is indicated by the Roman numerals I - VII. The largest stars are size I and our Sun is a dwarf of size V.
The following table may be helpful:
A number of different luminosity classes are distinguished:
I supergiants
Ia-0 (hypergiants or extremely luminous supergiants (later addition), Example: Eta Carinae (spectrum-peculiar)
Ia (luminous supergiants), Example: Deneb (spectrum is A2Ia)
Iab (intermediate luminous supergiants)
Ib (less luminous supergiants), Example: Betelgeuse (spectrum is M2Ib)
II bright giants
IIa, Example: β Scuti (HD 173764) (spectrum is G4 IIa)
IIab Example: HR 8752 (spectrum is G0Iab:)
IIb, Example: HR 6902 (spectrum is G9 IIb)
III normal giants
IIIa, Example: ρ Persei (spectrum is M4 IIIa)
IIIab Example: δ Reticuli (spectrum is M2 IIIab)
IIIb, Example: Pollux (spectrum is K2 IIIb)
IV subgiants
IVa, Example: ε Reticuli (spectrum is K1-2 IVa-III)
IVb, Example: HR 672 A (spectrum is G0.5 IVb)
V main sequence stars (dwarfs)
Va, Example: AD Leonis (spectrum M4Vae)
Vb, Example: 85 Pegasi A (spectrum G5 Vb)
VI subdwarfs (rarely used)
VII white dwarfsCan you please help me with my constellation project? it is....?Sagitta the Arrow is a small constellation and its brightest star has a magnitude of 3.5, not very bright. Do you mean Sagittarius the Archer? Its brightest stars look like a teapot. The Milky Way is very prominent here and there are many clusters and nebulae, including the Trifid and Lagoon. Great constellation to look at through binoculars on a summer evening in the southern sky.Can you please help me with my constellation project? it is....?here are some usefull web sites:
http://www.maa.mhn.de/Maps/Stars_en/Fig/sagitta.html
http://www.hawastsoc.org/deepsky/sge/index.html
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