30 Arietis (abbreviated 30 Ari) is a 6th- apparent-magnitude

multiple star system A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction. A large group of stars bound by gravitation is generally called a '' star cluster'' or '' galaxy'', although, broadly speaki ...

in the

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The origins of the e ...

Aries Aries may refer to: *Aries (astrology), an astrological sign *Aries (constellation), a constellation of stars in the zodiac Arts, entertainment and media * ''Aries'' (album), by Luis Miguel, 1993 * ''Aries'' (EP), by Alice Chater, 2020 * "Aries" ...

. ''30 Arietis'' is the

Flamsteed designation 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 co ...

. 30 Arietis A and B are separated by or about at a distance of 130

light year A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...

s away. The main components of both systems are both binaries with a composite spectra belonging to

F-type main-sequence star An F-type main-sequence star (F V) is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K.Tables VII ...

s, meaning they are fusing

hydrogen Hydrogen is the chemical element with the symbol H and atomic number 1. Hydrogen is the lightest element. At standard conditions hydrogen is a gas of diatomic molecules having the formula . It is colorless, odorless, tasteless, non-toxic, an ...

in their cores. The 30 Arietis system is 910 million years old, one fifth the age of the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

Star system

30 Arietis A and B are separated by 38.1", corresponding to 1,500 AU at a distance of 130

s. The pair are at almost the same distance, have very similar

proper motion Proper motion is the astrometric measure of the observed changes in the apparent places of stars or other celestial objects in the sky, as seen from the center of mass of the Solar System, compared to the abstract background of the more dista ...

s, and are considered almost certain to be gravitationally bound with a likely period around 34,000 years. The main components of both systems are both binaries with a composite spectra belonging to

s, meaning they are fusing

in their cores. 30 Arietis A is a

spectroscopic binary A binary star is a system of two star, stars that are gravity, gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separa ...

with an orbital period of 1.1 days. The primary Aa is an F-type main sequence star about 31% more massive than the Sun, while the companion Ab is a faint red dwarf only about 15% the mass of the Sun. 30 Arietis B has been reported to have a red dwarf companion at a distance of and another red dwarf Bb at about . In 2020, after the inclination of the planetary orbit was measured, the "planet" was found to fall in the mass range of a

brown Brown is a color. It can be considered a composite color, but it is mainly a darker shade of orange. In the CMYK color model used in printing or painting, brown is usually made by combining the colors orange and black. In the RGB color model used ...

red dwarf ''Red Dwarf'' is a British science fiction comedy franchise created by Rob Grant and Doug Naylor, which primarily consists of a television sitcom that aired on BBC Two between 1988 and 1999, and on Dave since 2009, gaining a cult following. T ...

. The more distant companion was referred to as C to distinguish it from Bb, and at about 0.5" it has been imaged using

adaptive optic Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of incoming wavefront distortions by deforming a mirror in order to compensate for the distortion. It is used in astronomical tele ...

30 Arietis Bb

30 Arietis Bb (sometimes abbreviated 30 Ari Bb) is a

which orbits the F-type

main sequence In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Her ...

star A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...

30 Arietis Ba, located in a quintuple star system approximately 146

s away in the

. The

was discovered by on Friday, November 27, 2009 by using precise

radial velocity method Doppler spectroscopy (also known as the radial-velocity method, or colloquially, the wobble method) is an indirect method for finding extrasolar planets and brown dwarfs from radial-velocity measurements via observation of Doppler shifts in t ...

from

echelle spectrograph An echelle grating (from French ''échelle'', meaning "ladder") is a type of diffraction grating characterised by a relatively low groove density, but a groove shape which is optimized for use at high incidence angles and therefore in high diffract ...

installed in the Alfred-Jensch telescope in

Karl Schwarzschild Observatory The Karl Schwarzschild Observatory (german: Karl-Schwarzschild-Observatorium) is a German astronomical observatory in Tautenburg near Jena, Thuringia. It was founded in 1960 as an affiliated institute of the former German Academy of Sciences at ...

. The star had a

minimum mass In astronomy, minimum mass is the lower-bound calculated mass of observed objects such as planets, stars and binary systems, nebulae, and black holes. Minimum mass is a widely cited statistic for extrasolar planets detected by the radial veloc ...

of nearly 10 times that of

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...

. In 2020, after the inclination of the planetary orbit was measured to be just 4.14°, the "planet" was found to fall in the mass range of red dwarf stars.

References

External links

Image 30 Arietis

Double stars

NASA diagram of the 30 Ari System
{{Sky, 02, 36, 00.5237, +, 24, 38, 50.000, 128.6 Aries (constellation) F-type main-sequence stars 5 Arietis, 30 Arietis, 30 0764/5 016232/46 BD+24 0375 012184/9

Star system

30 Arietis Bb

See also

References

External links