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Glossary

Names of Major Stars

a-b c-o p-z
NameBayerMag.Appendix
AchernarAlpha Eridani0.5 
AldebaranAlpha Tauri0.8 
AlgolBeta Persei2.1 (Max) 
AltairAlpha Aquilae0.8Member of the Summer Triangle, Hikoboshi or Kengyu in Tanabata story
AntaresAlpha Scorpii1.0 (Max) 
ArcturusAlpha Bootis-0.0Member of the Spring Triangle
BetelgeuseAlpha Orionis0.4 (Max)Member of the Winter Triangle
CanopusAlpha Carinae-0.7 
CapellaAlpha Aurigae0.1 
CastorAlpha Geminorum1.6 
DenebAlpha Cygni1.3Member of the Summer Triangle
DenebolaBeta Leonis2.1Member of the Spring Triangle
FomalhautAlpha Piscis Austrini1.2 
MiraOmicron Ceti2.0 (Max) 
PolarisAlpha Ursae Minoris2.0 
PolluxBeta Geminorum1.1 
ProcyonAlpha Canis Minoris0.4Member of the Winter Triangle
RegulusAlpha Leonis1.3 
RigelBeta Orionis0.1 
SiriusAlpha Canis Majoris-1.5Member of the Winter Triangle
SpicaAlpha Virginis1.0Member of the Spring Triangle
VegaAlpha Lyrae0.0Member of the Summer Triangle, Orihime in Tanabata story

Names of Stars

Proper Name

Proper names, for example Sirius, Vega and Altair are those used from ancient. Some comes from Greek, and some comes from Latin or Arabic. Mostly proper name expresses the character of the star.

Bayer Designation

German astronomer Johann Bayer introduced new designation of stars in his "Uranometria" (1603). He used Greek letter and the name of the constellation, for example, Alpha Canis Majoris. The order of Greek letter is mostly determined by magnitude of the star. When the constellation has more than the number of Greek letters, Latin alphabet can be used (lower-case, upper-case). Superscripts are used for double stars, and upper-case Latin alphabet after R and two-letter upper-case Latin alphabet are used for variable stars.

Flamsteed Designation (Flamsteed Number)

In order to express many stars, John Flamsteed, founder of the Royal Greenwich Observatory, employed sequential numbering of stars. The order of stars is determined by the right ascension.

Catalogue Number

Star catalogue contains a lot of information on stars such as position and magnitude. There are so many stars in the catalogue that we simply call the star as catalogue name + its sequential number. For example, HD 12345 is the 12345th star in the Hipparcos Catalogue. HD 45678 is the 45678th star in the Henry Draper Catalogue.

Relationship of Star Names

One star can have several names. For example Sirius is Alpha Canis Majoris in Bayer Designations, 9 Canis Majoris in Flamsteed Designations, HIP 32349 in Hipparcos Catalogue and HD 48915 in Henry Draper Catalogue. We used N.D. Kostjuk, HD-DM-GC-HR-HIP-Bayer-Flamsteed Cross Index (2002) to relate those names.


Distance to the star

Parallax

Position of a star changes as the Earth goes around the Sun. We can determine the distance to the stars using the apparent motion named parallax, and the distance between the Earth and the Sun.

Parallax is the proof that the Earth is moving round the Sun. But the parallax of Alpha Centauri, the nearest star, is only 0.7 arcsecond. In fact 16th century astronomer Tycho Brahe believed that Ptolemaic Theory was right since he did not observe any parallax.

Hipparcos satellite

Hipparcos satellite (1989) aimed at determining the parallax precisely. Its outcome is the Hipparcos catalogue, and we use its revised version (Hipparcos, the New Reduction, van Leeuwen, 2007). However, even Hipparcos catalogue has its limit, approximately 300 light years. Distance with * means the value is not accurate enough.