14 Herculis
Encyclopedia
14 Herculis or 14 Her is an orange dwarf
star
approximately 59 light-year
s away in the constellation
Hercules
. Because of its apparent magnitude
, the star cannot be seen with the naked eye
. As of 2006, it is thought that 14 Herculis has two extrasolar planet
s in orbit around the star.
star
of the spectral type "K0V." It is though that the star has only 79 percent the mass
of the Sun
, 88 percent of the radius
, and 75 percent of the luminosity
. The star appears to be 3.2 times as enriched with elements heavier than hydrogen
(based on its abundance of iron
).
was discovered to orbit 14 Herculis, which received the designation 14 Herculis b
. The planet is located in an eccentric, long-period orbit which takes around 4.8 years to complete. In 2005, a possible second planet was proposed, designated 14 Herculis c
. The parameters of this planet are uncertain, but a recent analysis suggests it may lie in the 4:1 resonance
with the inner planet, with an orbital period of almost 19 years at an orbital distance of 6.9 AU.
Orange dwarf
A K-type main-sequence star , also referred to orange dwarf, are main-sequence stars of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars and yellow G-type main-sequence stars...
star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
approximately 59 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....
Hercules
Hercules (constellation)
Hercules is a constellation named after Hercules, the Roman mythological hero adapted from the Greek hero Heracles. Hercules was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations today...
. Because of its apparent magnitude
Apparent magnitude
The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...
, the star cannot be seen with the naked eye
Naked eye
The naked eye is a figure of speech referring to human visual perception unaided by a magnifying or light-collecting optical device, such as a telescope or microscope. Vision corrected to normal acuity using corrective lenses is considered "naked"...
. As of 2006, it is thought that 14 Herculis has two extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
s in orbit around the star.
Stellar components
14 Herculis is an orange dwarfOrange dwarf
A K-type main-sequence star , also referred to orange dwarf, are main-sequence stars of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars and yellow G-type main-sequence stars...
star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...
of the spectral type "K0V." It is though that the star has only 79 percent the mass
Mass
Mass can be defined as a quantitive measure of the resistance an object has to change in its velocity.In physics, mass commonly refers to any of the following three properties of matter, which have been shown experimentally to be equivalent:...
of the Sun
Sun
The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...
, 88 percent of the radius
Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its...
, and 75 percent of the luminosity
Luminosity
Luminosity is a measurement of brightness.-In photometry and color imaging:In photometry, luminosity is sometimes incorrectly used to refer to luminance, which is the density of luminous intensity in a given direction. The SI unit for luminance is candela per square metre.The luminosity function...
. The star appears to be 3.2 times as enriched with elements heavier than hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
(based on its abundance of iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
).
Planetary system
In 1998 an extrasolar planetExtrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...
was discovered to orbit 14 Herculis, which received the designation 14 Herculis b
14 Herculis b
14 Herculis b or 14 Her b is an extrasolar planet approximately 59 light-years away in the constellation of Hercules. The planet was found orbiting the star 14 Herculis, with a mass that would likely make the planet a Jovian planet roughly the same size as Jupiter but much more massive. It was...
. The planet is located in an eccentric, long-period orbit which takes around 4.8 years to complete. In 2005, a possible second planet was proposed, designated 14 Herculis c
14 Herculis c
14 Herculis c or 14 Her c is an extrasolar planet approximately 59 light-years away in the constellation of Hercules. The planet was found orbiting the star 14 Herculis, with a mass that would likely make the planet a gas giant roughly the same size as Jupiter but much more massive. This planet...
. The parameters of this planet are uncertain, but a recent analysis suggests it may lie in the 4:1 resonance
Orbital resonance
In celestial mechanics, an orbital resonance occurs when two orbiting bodies exert a regular, periodic gravitational influence on each other, usually due to their orbital periods being related by a ratio of two small integers. Orbital resonances greatly enhance the mutual gravitational influence of...
with the inner planet, with an orbital period of almost 19 years at an orbital distance of 6.9 AU.
See also
- 47 Ursae Majoris47 Ursae Majoris47 Ursae Majoris is a solar analog, yellow dwarf star approximately 46 light-years away from Earth in the constellation of Ursa Major. , it has been confirmed that three Jupiter-like extrasolar planets orbit the star...
- List of stars in Hercules
- List of extrasolar planets