Kepler-6
Encyclopedia
Kepler-6 is a yellow giant situated in the constellation Cygnus
. The star lies within the field of view of the Kepler Mission
, which discovered it as part of a NASA
-led mission to discover Earth-like planets
. The star, which is slightly larger, more metal-rich, slightly cooler, and more massive than the Sun
, is orbited by at least one extrasolar planet
, a Jupiter
-sized planet named Kepler-6b
that orbits closely to its star.
, a NASA
project launched in 2009 that aims to discover Earth-like
planets that transit, or cross in front of, their home stars with respect to Earth
. Unlike stars like the Sun
or Sirius
, Kepler-6 does not have a common and colloquial name. The discovery of Kepler-6b was announced by the Kepler team on January 4, 2010 at the 215th meeting of the American Astronomical Society
along with planets around Kepler-4
, Kepler-5
, Kepler-7
, and Kepler-8
. It was the third planet to be discovered by the Kepler spacecraft; the first three planets to be verified by data from Kepler had been previously discovered. These three planets were used to test the accuracy of Kepler's measurements.
The discovery of Kepler-6 was confirmed by follow-up observations made using the Hobby Eberly
and Smith telescopes in Texas
; the Keck 1 telescope in Hawaii
; the Hale
and Shane
telescopes in southern California
; the WIYN, MMT
, and Tillinghast
telescopes in Arizona
; and the Nordic Optical Telescope
in the Canary Islands
.
, or some five-fourths the mass of the Sun
. It is also wider than the sun, with a radius of 1.391 Rsun, or seven-fifths of that of the Sun. The star is approximately 3.8 billion years old, and has an effective temperature
of 5647 K (9,705 °F). In comparison, the Sun has a slightly warmer temperature of 5778 K. Kepler-6 has a metallicity
of [Fe/H] = +0.34, making it 2.2 times more metallic than the Sun. On average, metal-rich stars tend to be more likely to have planets and planetary systems.
The star, as seen from Earth, has an apparent magnitude
of 13.8. It is not visible with the naked eye. In comparison, Pluto
's apparent magnitude at its brightest is slightly brighter, at 13.65.
. The planet is approximately .669 MJ
, or some two-thirds the mass of planet Jupiter
. It is also slightly more diffuse than Jupiter, with a radius of approximately 1.323 RJ. Kepler-6b orbits at an average distance of .0456 AU
from its star, and completes an orbit every 3.234 days. The eccentricity
of the planet's orbit is assumed to be 0, which is that of a circular orbit.
Cygnus (constellation)
Cygnus is a northern constellation lying on the plane of the Milky Way. Its name is the Latinized Hellenic word for swan. One of the most recognizable constellations of the northern summer and autumn, it features a prominent asterism known as the Northern Cross...
. The star lies within the field of view of the Kepler Mission
Kepler Mission
The Kepler spacecraft is an American space observatory, the space-based portion of NASA's Kepler Mission to discover Earth-like planets orbiting other stars. The spacecraft is named in honor of the 17th-century German astronomer Johannes Kepler...
, which discovered it as part of a NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
-led mission to discover Earth-like planets
Terrestrial planet
A terrestrial 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 are the inner planets closest to the Sun...
. The star, which is slightly larger, more metal-rich, slightly cooler, and more massive than 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...
, is orbited by at least one 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...
, a Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
-sized planet named Kepler-6b
Kepler-6b
Kepler-6b is an extrasolar planet in the orbit of the unusually metal-rich Kepler-6, a star in the field of view of the NASA-operated Kepler spacecraft, which searches for planets that cross directly in front of, or transit, their host stars. It was the third planet to be discovered by Kepler....
that orbits closely to its star.
Nomenclature and history
Kepler-6 was named for the Kepler MissionKepler Mission
The Kepler spacecraft is an American space observatory, the space-based portion of NASA's Kepler Mission to discover Earth-like planets orbiting other stars. The spacecraft is named in honor of the 17th-century German astronomer Johannes Kepler...
, a NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...
project launched in 2009 that aims to discover Earth-like
Terrestrial planet
A terrestrial 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 are the inner planets closest to the Sun...
planets that transit, or cross in front of, their home stars with respect to Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
. Unlike stars like 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...
or Sirius
Sirius
Sirius is the brightest star in the night sky. With a visual apparent magnitude of −1.46, it is almost twice as bright as Canopus, the next brightest star. The name "Sirius" is derived from the Ancient Greek: Seirios . The star has the Bayer designation Alpha Canis Majoris...
, Kepler-6 does not have a common and colloquial name. The discovery of Kepler-6b was announced by the Kepler team on January 4, 2010 at the 215th meeting of the American Astronomical Society
American Astronomical Society
The American Astronomical Society is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC...
along with planets around Kepler-4
Kepler-4
Kepler-4 is a sunlike star located about 1631 light-years away in the constellation Draco. It is in the field of view of the Kepler Mission, a NASA operation purposed with finding Earth-like planets. Kepler-4b, a Neptune-sized planet that orbits extremely close to its star, was discovered in its...
, Kepler-5
Kepler-5
Kepler-5 is a star located in the constellation Cygnus in the field of view of the Kepler Mission, a NASA project aimed at detecting planets in transit of, or passing in front of, their host stars as seen from Earth. One closely orbiting, Jupiter-like planet, named Kepler-5b, has been detected...
, Kepler-7
Kepler-7
Kepler-7 is a star located in the constellation Lyra in the field of view of the Kepler Mission, a NASA operation in search of Earth-like planets. It is home to the fourth of the first five planets that Kepler discovered; this planet, a Jupiter-size gas giant named Kepler-7b, is as light as styrofoam...
, and Kepler-8
Kepler-8
| class=F5VKepler-8 is a star located in the constellation Lyra in the field of view of the Kepler Mission, a NASA-led operation tasked with discovering terrestrial planets. The star, which is slightly hotter, larger, and more massive than the Sun, has one gas giant in its orbit, Kepler-8b. This...
. It was the third planet to be discovered by the Kepler spacecraft; the first three planets to be verified by data from Kepler had been previously discovered. These three planets were used to test the accuracy of Kepler's measurements.
The discovery of Kepler-6 was confirmed by follow-up observations made using the Hobby Eberly
Hobby-Eberly Telescope
The Hobby-Eberly Telescope is a 9.2-meter aperture telescope located at the McDonald Observatory. It combines a number of features that differentiate it from most telescope designs, resulting in greatly lowered construction costs...
and Smith telescopes in Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...
; the Keck 1 telescope in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
; the Hale
Hale telescope
The Hale Telescope is a , 3.3 reflecting telescope at the Palomar Observatory in California, named after astronomer George Ellery Hale. With funding from the Rockefeller Foundation, he orchestrated the planning, design, and construction of the observatory, but did not live to see its commissioning...
and Shane
C. Donald Shane telescope
The C. Donald Shane telescope is a reflecting telescope located at the Lick Observatory in California. It was named after astronomer C. Donald Shane in 1978, who led the effort to acquire the necessary funds from the California Legislature, and who then oversaw the telescope's construction...
telescopes in southern California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
; the WIYN, MMT
MMT Observatory
The MMT Observatory is an astronomical observatory on the site of Fred Lawrence Whipple Observatory . The Whipple observatory complex is located on Mount Hopkins, Arizona, USA in the Santa Rita Mountains...
, and Tillinghast
Fred Lawrence Whipple Observatory
The Fred Lawrence Whipple Observatory is an astronomical observatory owned and operated by the Smithsonian Astrophysical Observatory and is their largest field installation outside of their main site in Cambridge, MA...
telescopes in Arizona
Arizona
Arizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
; and the Nordic Optical Telescope
Nordic Optical Telescope
The Nordic Optical Telescope is an astronomical telescope located at Roque de los Muchachos Observatory, La Palma in the Canary Islands. First light came in 1988, with regular observing beginning in 1989. It is funded by Denmark, Sweden, Iceland, Norway and Finland...
in the Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...
.
Characteristics
Kepler-6 is a star that is approximately 1.209 MsunSolar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...
, or some five-fourths the mass 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...
. It is also wider than the sun, with a radius of 1.391 Rsun, or seven-fifths of that of the Sun. The star is approximately 3.8 billion years old, and has an effective temperature
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...
of 5647 K (9,705 °F). In comparison, the Sun has a slightly warmer temperature of 5778 K. Kepler-6 has a metallicity
Metallicity
In astronomy and physical cosmology, the metallicity of an object is the proportion of its matter made up of chemical elements other than hydrogen and helium...
of [Fe/H] = +0.34, making it 2.2 times more metallic than the Sun. On average, metal-rich stars tend to be more likely to have planets and planetary systems.
The star, as seen from Earth, has an 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...
of 13.8. It is not visible with the naked eye. In comparison, Pluto
Pluto
Pluto, formal designation 134340 Pluto, is the second-most-massive known dwarf planet in the Solar System and the tenth-most-massive body observed directly orbiting the Sun...
's apparent magnitude at its brightest is slightly brighter, at 13.65.
Planetary system
Kepler-6 has one confirmed extrasolar planet; it is a gas giant named Kepler-6bKepler-6b
Kepler-6b is an extrasolar planet in the orbit of the unusually metal-rich Kepler-6, a star in the field of view of the NASA-operated Kepler spacecraft, which searches for planets that cross directly in front of, or transit, their host stars. It was the third planet to be discovered by Kepler....
. The planet is approximately .669 MJ
Jupiter mass
Jupiter mass , is the unit of mass equal to the total mass of the planet Jupiter . Jupiter mass is used to describe masses of the gas giants, such as the outer planets and extrasolar planets. It is also used in describing brown dwarfs....
, or some two-thirds the mass of planet Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
. It is also slightly more diffuse than Jupiter, with a radius of approximately 1.323 RJ. Kepler-6b orbits at an average distance of .0456 AU
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
from its star, and completes an orbit every 3.234 days. The eccentricity
Orbital eccentricity
The orbital eccentricity of an astronomical body is the amount by which its orbit deviates from a perfect circle, where 0 is perfectly circular, and 1.0 is a parabola, and no longer a closed orbit...
of the planet's orbit is assumed to be 0, which is that of a circular orbit.