Alpha Centauri
For other uses, see Alpha Centauri (disambiguation).
- Alpha Centauri268 related topics
K-type main-sequence star
Orange dwarf, is a main-sequence star of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars ("red dwarfs") and yellow/white G-type main-sequence stars.
Well-known examples include Alpha Centauri B (K1 V) and Epsilon Indi (K5 V).
Proxima Centauri
Small, low-mass star located 4.2465 ly away from the Sun in the southern constellation of Centaurus.
Proxima Centauri is a member of the Alpha Centauri star system, being identified as component Alpha Centauri C, and is 2.18° to the southwest of the Alpha Centauri AB pair.
Centaurus
Bright constellation in the southern sky.
Notable stars include Alpha Centauri, the nearest star system to the Solar System, its neighbour in the sky Beta Centauri, and V766 Centauri, one of the largest stars yet discovered.
G-type main-sequence star
Main-sequence star (luminosity class V) of spectral type G. Such a star has about 0.9 to 1.1 solar masses and an effective temperature between about 5,300 and 6,000 K.
Besides the Sun, other well-known examples of G-type main-sequence stars include Alpha Centauri, Tau Ceti, Capella and 51 Pegasi.
List of nearest stars and brown dwarfs
This list covers all known stars, brown dwarfs, and sub-brown dwarfs within 5.0 pc of the Solar System.
The Local Bubble also contains the neighboring G-Cloud, which contains the stars Alpha Centauri and Altair.
Star system
Small number of stars that orbit each other, bound by gravitational attraction.
Alpha Centauri is a triple star composed of a main binary yellow dwarf pair (Alpha Centauri A and Alpha Centauri B), and an outlying red dwarf, Proxima Centauri. Together, A and B form a physical binary star, designated as Alpha Centauri AB, α Cen AB, or RHD 1 AB, where the AB denotes this is a binary system. The moderately eccentric orbit of the binary can make the components be as close as 11 AU or as far away as 36 AU. Proxima Centauri, also (though less frequently) called Alpha Centauri C, is much farther away (between 4300 and 13,000 AU) from α Cen AB, and orbits the central pair with a period of 547,000 (+66,000/-40,000) years.
List of brightest stars
List of stars arranged by their apparent magnitude – their brightness as observed from Earth.
Stellar brightness is traditionally based on the apparent visual magnitude as perceived by the human eye, from the brightest stars of 1st magnitude to the faintest at 6th magnitude. Since the invention of the optical telescope and the documenting of binary stars and multiple star systems, stellar brightness could be expressed as either individual (separate) or total (combined) magnitude. The table is ordered by combined magnitude of all naked eye components appearing as if it they were single stars. Such multiple star systems are indicated by parentheses showing the individual magnitudes of component stars bright enough to make a detectable contribution. For example, the double star Alpha Centauri has the total or combined magnitude of −0.27, while its two component stars have magnitudes of +0.01 and +1.33.
Canopus
Brightest star in the southern constellation of Carina and the second-brightest star in the night sky.
English explorer Robert Hues brought Canopus to the attention of European observers in his 1592 work Tractatus de Globis, along with Achernar and Alpha Centauri, noting: "Now, therefore, there are but three Stars of the first magnitude that I could perceive in all those parts which are never seene here in England. The first of these is that bright Star in the sterne of Argo which they call Canobus. The second is in the end of Eridanus. The third is in the right foote of the Centaure."
Brown dwarf
Brown dwarfs are substellar objects that are not massive enough to sustain nuclear fusion of ordinary hydrogen (1H) into helium in their cores, unlike a main-sequence star.
Luhman 16 is the third closest system to the Sun after Alpha Centauri and Barnard's Star.
Binary star
System of two stars that are gravitationally bound to and in orbit around each other.
Orbital periods can be less than an hour (for AM CVn stars), or a few days (components of Beta Lyrae), but also hundreds of thousands of years (Proxima Centauri around Alpha Centauri AB).