Delta² Chamaeleontis, Latinized from δ² Chamaeleontis, is a solitary

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

located in the southern

circumpolar constellation A circumpolar star is a star that, as viewed from a given latitude on Earth, never sets below the horizon due to its apparent proximity to one of the celestial poles. Circumpolar stars are therefore visible from said location toward the nearest p ...

Chamaeleon Chamaeleon () is a small constellation in the deep southern sky. It is named after the chameleon, a kind of lizard. It was first defined in the 16th century. History Chamaeleon was one of twelve constellations created by Petrus Plancius f ...

. It has an

apparent visual magnitude Apparent magnitude () is a measure of the brightness of a star, astronomical object or other celestial objects like artificial satellites. Its value depends on its intrinsic luminosity, its distance, and any extinction of the object's light ca ...

of 4.42, which is bright enough for the star to be seen with the naked eye. Based upon an annual parallax shift of 9.30 mas, it is located around 351

light year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distance, astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by t ...

s from the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

. This star is one of two stars named Delta Chamaeleontis, the other being the fainter Delta¹ Chamaeleontis located about 6

arcminute A minute of arc, arcminute (abbreviated as arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of a degree. Since one degree is of a turn, or complete rotation, one arcminute is of a tu ...

s away. Delta Chamaeleontis forms the southernmost component of the constellation's "dipper" or bowl. Together with

Gamma Chamaeleontis Gamma Chamaeleontis, Latinized from γ Chamaeleontis, is a solitary star located in the southern circumpolar constellation of Chamaeleon. It can faintly be seen with the naked eye on a dark night, having an apparent visual magnitude of 4.1 ...

, they point to a spot that is within 2° of the south

celestial pole The north and south celestial poles are the two points in the sky where Earth's axis of rotation, indefinitely extended, intersects the celestial sphere. The north and south celestial poles appear permanently directly overhead to observers at ...

. This is a

B-type main sequence star A B-type main-sequence star (B V) is a main-sequence (hydrogen-burning) star of spectral type B and luminosity class V. These stars have from 2 to 16 times the mass of the Sun and surface temperatures between 10,000 and 30,000 K. B-type stars ...

with a

stellar classification In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction gratin ...

of B3 V. However, Hiltner et al. (1969) give a classification of B2.5 IV, which would suggest it is a more

evolved Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

subgiant star A subgiant is a star that is brighter than a normal main-sequence star of the same spectral class, but not as bright as giant stars. The term subgiant is applied both to a particular spectral luminosity class and to a stage in the evolution of ...

. It is estimated to have five times the

mass of the Sun The solar mass () is a frequently used unit of mass in astronomy, equal to approximately . It is approximately equal to the mass of the Sun. It is often used to indicate the masses of other stars, as well as stellar clusters, nebulae, galaxies a ...

and 3.9 times the

Sun's radius Solar radius is a unit of distance used to express the size of objects in astronomy relative to the Sun. The solar radius is usually defined as the radius to the layer in the Sun's photosphere where the optical depth equals 2/3: 1\,R_ = 6.957\ti ...

. With an age of 32.6 million years, it is radiating over 500 times the

solar luminosity The solar luminosity () is a unit of radiant flux (Power (physics), power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxy, galaxies and other celestial objects in terms of the output of ...

from its outer atmosphere at an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of 15,873 K. There is a 70% likelihood that this star is a member of

Gould's Belt The Gould Belt is a local ring of stars in the Milky Way, tilted away from the galactic plane by about 16–20 degrees, first reported by John Herschel and Benjamin Gould in the 19th century. It contains many O- and B-type stars, and many of ...

References

{{DEFAULTSORT:Delta2 Chamaeleontis Chamaeleontis, Delta2 Chamaeleon Chamaeleontis, Delta2 Durchmusterung objects 052633 04234 093845 B-type subgiants