A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named for John Flamsteed who first used them while compiling his Historia Coelestis Britannica . (Flamsteed used a telescope, [1] and the catalog also includes some stars which are relatively bright but not necessarily visible with the naked eye.)
Flamsteed designations for stars are similar to Bayer designations, except that they use numbers instead of Greek and Roman letters. Each star is assigned a number and the Latin genitive of the constellation it lies in (see 88 modern constellations for a list of constellations and the genitive forms of their names). Flamsteed designations were assigned to 2554 stars. The numbers were originally assigned in order of increasing right ascension within each constellation, but due to the effects of precession they are now slightly out of order in some places.
This method of designating stars first appeared in a preliminary version of John Flamsteed's Historia Coelestis Britannica published by Edmond Halley and Isaac Newton in 1712 without Flamsteed's approval. [2] [3] The final version of Flamsteed's catalogue published in 1725 [4] after his death omitted the numerical designations altogether. The numbers now in use were assigned by the French astronomer, Joseph Jérôme de Lalande and appeared in his 1783 almanac, Éphémérides des mouvemens célestes which contained a revised edition of Flamsteed’s catalogue. [5] Lalande noted in his Introduction that he got the idea from the unofficial 1712 edition. [6]
Flamsteed designations gained popularity throughout the eighteenth century, and are now commonly used when no Bayer designation exists. Where a Bayer designation with a Greek letter does exist for a star, it is usually used in preference to the Flamsteed designation. (Flamsteed numbers are generally preferred to Bayer designations with Roman letters.) Examples of well-known stars that are usually referred to by their Flamsteed numbers include 51 Pegasi, and 61 Cygni. Flamsteed designations are often used instead of the Bayer designation if the latter contains an extra attached number; for example, "55 Cancri" is more common than "Rho1 Cancri".
There are examples of stars, such as 10 Ursae Majoris in Lynx, bearing Flamsteed designations for constellations in which they do not lie, just as there are for Bayer designations, because of the compromises that had to be made when the modern constellation boundaries were drawn up.
Flamsteed's catalogue covered only the stars visible from Great Britain, and therefore stars of the far southern constellations have no Flamsteed numbers. Some stars, such as the nearby star 82 Eridani, were named in a major southern-hemisphere catalog called Uranometria Argentina, by Benjamin Gould; these are Gould numbers, rather than Flamsteed numbers, and should be differentiated with a G, as in 82 G. Eridani. Except for a handful of cases, Gould numbers are not in common use. Similarly, Flamsteed-like designations assigned by other astronomers (for example, Hevelius) are no longer in general use. (A well-known exception is the globular cluster 47 Tucanae from Bode's catalog.)
84 stars entered in Flamsteed's catalog are errors and proved not to exist in the sky: [7] All of them except 11 Vulpeculae were plotted on his star charts.
There are 52 constellations that primarily use Flamsteed designations. Stars are listed in the appropriate lists for the constellation, as follows:
In addition, several stars in Puppis, and a small number of stars in Centaurus and Lupus, have been given Flamsteed designations.
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. The brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas Uranometria. Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers supplemented Bayer's catalog with entries for southern constellations.
Abbé Nicolas-Louis de Lacaille, formerly sometimes spelled de la Caille, was a French astronomer and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the Cape of Good Hope in present-day South Africa. Lacaille observed over 10,000 stars using just a half-inch refracting telescope.
In astronomy, stars have a variety of different stellar designations and names, including catalogue designations, current and historical proper names, and foreign language names.
John Flamsteed was an English astronomer and the first Astronomer Royal. His main achievements were the preparation of a 3,000-star catalogue, Catalogus Britannicus, and a star atlas called Atlas Coelestis, both published posthumously. He also made the first recorded observations of Uranus, although he mistakenly catalogued it as a star, and he laid the foundation stone for the Royal Greenwich Observatory.
Epsilon Eridani, proper name Ran, is a star in the southern constellation of Eridanus. At a declination of −9.46°, it is visible from most of Earth's surface. Located at a distance 10.5 light-years from the Sun, it has an apparent magnitude of 3.73, making it the third-closest individual star visible to the naked eye.
The year 1783 in science and technology involved some significant events:
Xi Andromedae, officially named Adhil, is a solitary star in the northern constellation of Andromeda. It has an apparent magnitude of +4.9. Based on parallax measurements obtained during the Gaia mission, it lies at a distance of roughly 223 light-years from the Sun.
13 Cancri is a K-type giant star in the constellation Cancer. It has an apparent magnitude of +6.41 and is approximately 970 light years from Earth.
Omicron1 Canis Majoris is a red supergiant star in the constellation Canis Major. It is also a variable star.
53 Eridani, also designated l Eridani, is a binary star in the constellation of Eridanus. The system has a combined apparent magnitude of 3.87. Parallax estimates made by the Hipparcos spacecraft put it at a distance of about 110 light-years, or 33.7 parsecs, from the Sun.
The Bayer designation Sigma Cancri is shared by three star systems, in the constellation Cancer:
Histoire céleste française is an astrometric star catalogue published in 1801 by the French astronomer Jérôme Lalande and his staff at the Paris Observatory. This star catalog consists of the locations and apparent magnitudes of 47,390 stars, up to magnitude 9. Stars are identified by common name, Bayer designation or Flamsteed designation, when available. It also contains observations of other astronomical phenomena. It was the largest and most complete star catalog of its day. This publication is a collection of several books of astronomical recordings taken over the previous decade at the observatory.
Gould designations for stars are similar to Flamsteed designations in the way that they number stars within a constellation in increasing order of right ascension. Each star is assigned an integer, followed by " G. ", and then the Latin genitive of the constellation it lies in. See 88 modern constellations for a list of constellations and the genitive forms of their names.
AR Cassiopeiae is a variable star in the constellation of Cassiopeia. It is thought to be a member of a septuple star system, one of only two known star systems with a multiplicity of 7, the other being Nu Scorpii.
The Atlas Coelestis is a star atlas published posthumously in 1729, based on observations made by the First Astronomer Royal, John Flamsteed.
56 Ceti is a single star located in the equatorial constellation of Cetus. Not found in the original Bayer catalogue, it was given the Bayer-like designation Upsilon1 Ceti by Flamsteed to distinguish it from Bayer's Upsilon Ceti, which Flamsteed designated Upsilon2 or 59 Ceti. In 1801, J. E. Bode included this designation in his Uranographia, but the superscripted designations Upsilon1 and Upsilon2 are not in general use today. 56 Ceti is the Flamsteed designation for this star.
9 Pegasi is a supergiant star in the constellation Pegasus. Its apparent magnitude is 4.35.
68 Cygni is the Flamsteed designation for a star in the constellation Cygnus. Located approximately 1,400 parsecs (4,600 ly) distant, the star is a hot blue giant of spectral type O7.5IIIn( ), a massive star that is likely currently expanding to become a supergiant. The star is surrounded by a ring-shaped nebula named S 119.
This table lists those stars/objects which have Flamsteed designations by the constellation in which those stars/objects lie. The name given is that of the article if it does not reflect the Flamsteed designation. Some articles are linked twice, in cases where the star has been assigned two different Flamsteed designations, usually as noted in different constellations.