ι Serpentis, Latinized as Iota Serpentis and abbreviated Iot Ser, is a

triple star 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 speaking ...

system in the

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

Serpens, in its head (Serpens Caput). It is approximately 190 light years from

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's sur ...

. At the centre of the system is a

spectroscopic binary A binary star is a system of two stars that are 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 separate stars, in w ...

, Iota Serpentis A and B. These are both white main sequence dwarfs and both have

apparent magnitude Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's ...

s of +5.3. This binary has an orbital period variously reported as 11 or 22 years. First discovered as an

astrometric binary A binary star is a system of two stars that are 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 separate stars, in w ...

, the pair have now been resolved and visual orbits have been derived. There are two visual companions, Iota Serpentis C, a 13th magnitude star 143

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

s away and Iota Serpentis D, a 12th magnitude star 151

s distant.

References

{{DEFAULTSORT:Iota Serpentis A-type main-sequence stars Spectroscopic binaries Triple star systems Serpens (constellation) Serpentis, Iota Durchmusterung objects Serpentis, 21 140159 076852 5842