HD 147513 (62 G. Scorpii) is a star in the southern

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 first constellati ...

Scorpius Scorpius is a zodiac constellation located in the Southern celestial hemisphere, where it sits near the center of the Milky Way, between Libra to the west and Sagittarius to the east. Scorpius is an ancient constellation whose recognition pred ...

. It was first catalogued by Italian astronomer Piazzi in his

star catalogue A star catalogue is an astronomical catalogue that lists stars. In astronomy, many stars are referred to simply by catalogue numbers. There are a great many different star catalogues which have been produced for different purposes over the year ...

as "XVI 55". With an

apparent magnitude Apparent magnitude () is a measure of the Irradiance, 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 (astronomy), ...

of 5.38, according to the Bortle scale it is visible to the naked eye from suburban skies. Based upon

stellar parallax Stellar parallax is the apparent shift of position (''parallax'') of any nearby star (or other object) against the background of distant stars. By extension, it is a method for determining the distance to the star through trigonometry, the stel ...

measurements by the

Hipparcos ''Hipparcos'' was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions and distances of ...

spacecraft, HD 147513 lies some 42

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.

Properties

This is a

Sun-like Solar-type stars, solar analogs (also analogues), and solar twins are stars that are particularly similar to the Sun. The stellar classification is a hierarchy with solar twin being most like the Sun followed by solar analog and then solar-typ ...

main sequence In astronomy, the main sequence is a classification of stars which appear on plots of stellar color index, color versus absolute magnitude, brightness as a continuous and distinctive band. Stars on this band are known as main-sequence stars or d ...

star 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 G1V CH-04. It has about 5% greater mass than the Sun, and is considered young with an estimated age of 400 million years. As such, it has a similar luminosity to the Sun despite being more massive. Although the abundance of elements is similar to the Sun, it is a Barium star that is overabundant in elements produced through the

s-process The slow neutron-capture process, or ''s''-process, is a series of nuclear reactions, reactions in nuclear astrophysics that occur in stars, particularly asymptotic giant branch stars. The ''s''-process is responsible for the creation (nucleosynt ...

. HD 147513 is suspected of being a

variable star A variable star is a star whose brightness as seen from Earth (its apparent magnitude) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are ...

.NSV 7680 -- Variable Star
- SIMBAD entry HD 147513 is a member of the

Ursa Major moving group The Ursa Major Moving Group, also known as Collinder 285 and the Ursa Major association, is the closest Stellar kinematics#Moving groups, stellar moving group – a set of stars with common velocities in space and thought to have a common orig ...

that share a common

proper motion Proper motion is the astrometric measure of changes in the apparent places of stars or other celestial objects as they move relative to the center of mass of the Solar System. It is measured relative to the distant stars or a stable referenc ...

through space. It has a nearby co-moving companion: a DA-class

white dwarf A white dwarf is a Compact star, stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very density, dense: in an Earth sized volume, it packs a mass that is comparable to the Sun. No nuclear fusion takes place i ...

located some 5,360 AU distant, where an AU is the average separation of the Earth from the Sun. At one time the pair may have been members of a multiple star system. The progenitor of the white dwarf may have been a closer companion, and while passing through the

asymptotic giant branch The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars. This is a period of stellar evolution undertaken by all low- to intermediate-mass stars (about 0.5 to 8 solar masses) lat ...

stage of its evolution, could have transferred matter onto HD 147513 and contaminated this star's photosphere.

Planetary system

In 2002, the Geneva Extrasolar Planet Search Team announced the discovery of an

extrasolar planet An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first detect ...

orbiting the star. Based upon the orbital elements, most of this

gas giant A gas giant is a giant planet composed mainly of hydrogen and helium. Jupiter and Saturn are the gas giants of the Solar System. The term "gas giant" was originally synonymous with "giant planet". However, in the 1990s, it became known that Uranu ...

's orbit lies within the

habitable zone In astronomy and astrobiology, the habitable zone (HZ), or more precisely the circumstellar habitable zone (CHZ), is the range of orbits around a star within which a planetary surface can support liquid water given sufficient atmospheric pressu ...

(HZ) of the host star; it only passes outside this region at

apogee An apsis (; ) is the farthest or nearest point in the orbit of a planetary body about its primary body. The line of apsides (also called apse line, or major axis of the orbit) is the line connecting the two extreme values. Apsides perta ...

. As such, it is unlikely that a

terrestrial planet A terrestrial planet, tellurian planet, telluric planet, or rocky planet, is a planet that is composed primarily of silicate, rocks or metals. Within the Solar System, the terrestrial planets accepted by the IAU are the inner planets closest to ...

could have a stable orbit within the HZ unless it moves in a synchronized fashion with the gas giant. Numerical simulations suggest that such a planet could orbit within the L₄ or L₅

Lagrangian point In celestial mechanics, the Lagrange points (; also Lagrangian points or libration points) are points of equilibrium (mechanics), equilibrium for small-mass objects under the gravity, gravitational influence of two massive orbit, orbiting b ...

s of the gas giant.

References

External links

* {{Sky, 16, 24, 01.2899, -, 39, 11, 34.729, 41.96 G-type main-sequence stars Suspected variables Barium stars HD, 147513 Scorpii, 62 Durchmusterung objects 9559 147513 080337 6094 Planetary systems with one confirmed planet