, - style="background-color: #A0B0FF;" colspan="3"
, Planet
, - bgcolor="#FFFAFA"
, HD 222582 b ,
Data Simbad, - bgcolor="#FFFAFA"
, ,
Data ExoPlanet
HD 222582 is a multiple
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 ...
system in the
equatorial 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 ...
of
Aquarius. It is invisible to the naked eye with an
apparent visual magnitude of 7.7,
[ but can be viewed with binoculars or a small telescope.][ The system is located at a distance of 138 ]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 from the Sun based on parallax
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...
,radial velocity
The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the temporal rate of change, rate of change of the distance or Slant range, range between the two points. It is e ...
of +12 km/s.[ It is located close enough to the ecliptic that it is subject to lunar occultations.][
The primary member of this system, designated component A, is an ordinary ]G-type main-sequence star
A G-type main-sequence star (Spectral type: G-V), also often, and imprecisely called a yellow dwarf, or G star, is a 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 temp ...
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 grati ...
of G5V.[ The physical properties of the star are similar enough to the Sun that it is considered a candidate solar twin.][ It is about 6.5][ billion years old with an inactive chromosphere][ and is spinning with a low projected rotational velocity of 1.7 km/s.][ The mass][ and ]metallicity
In astronomy, metallicity is the abundance of elements present in an object that are heavier than hydrogen and helium. Most of the normal physical matter in the Universe is either hydrogen or helium, and astronomers use the word ''"metals"'' as a ...
[ of this star are essentially the same as the Sun. It has a 14% larger radius and is radiating 1.3 times the luminosity of the Sun from its ]photosphere
The photosphere is a star's outer shell from which light is radiated.
The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it ...
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 5,790 K.[
Component B of this system is a close binary][ and about 20% the mass of the Sun.][
]
Planetary system
In November 1999, a dense superjovian
A super-Jupiter is a gas giant exoplanet that is more massive than the planet Jupiter. For example, companions at the planet–brown dwarf borderline have been called super-Jupiters, such as around the star Kappa Andromedae.
By 2011 there were ...
planet was announced orbiting the primary by the California and Carnegie Planet Search
California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...
. Designated component 'b', it was discovered using the 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 ...
, using 24 observations over a period of 1.5 years. The exoplanet is orbiting with a period of and a very large eccentricity of 0.76, ranging in distance from out to away from the primary.
See also
* HD 224693
* List of extrasolar planets
References
External links
*
{{DEFAULTSORT:HD 222582
G-type main-sequence stars
M-type main-sequence stars
Solar twins
Planetary systems with one confirmed planet
Triple stars
Aquarius (constellation)
BD-06 6262
222582
116906
J23415154-0559086