Kepler-5 is a

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 ...

located in the

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 ...

Cygnus in the field of view of the

Kepler Mission The Kepler space telescope is a disused space telescope launched by NASA in 2009 to discover Earth-sized planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched into an Earth-trailing heliocentric orb ...

, a

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

project aimed at detecting planets in transit of, or passing in front of, their host stars as seen 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 surfa ...

. One closely orbiting,

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but ...

-like planet, named Kepler-5b, has been detected around Kepler-5. Kepler-5's planet was one of the first five planets to be discovered by the Kepler spacecraft; its discovery was announced on January 4, 2010 at the 215th meeting of the American Astronomical Society after being verified by a variety of observatories. Kepler-5 is larger and more massive than the

Sun The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...

, but has a similar

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 ...

, a major factor in planet formation.

Nomenclature and history

Three discoveries made prior to the

Kepler mission The Kepler space telescope is a disused space telescope launched by NASA in 2009 to discover Earth-sized planets orbiting other stars. Named after astronomer Johannes Kepler, the spacecraft was launched into an Earth-trailing heliocentric orb ...

, which were in Kepler's field of view, were given the Kepler designations 1, 2 and 3. Kepler-5 is actually the second planet-bearing star discovered during the course of the Kepler Mission, a

operation that seeks to discover Earth-like planets that

transit Transit may refer to: Arts and entertainment Film * ''Transit'' (1979 film), a 1979 Israeli film * ''Transit'' (2005 film), a film produced by MTV and Staying-Alive about four people in countries in the world * ''Transit'' (2006 film), a 2006 ...

, or cross in front of, their host stars with respect to

. The star's planet, Kepler-5b, was therefore the second of the first five planets to be announced to the public on January 4, 2010 at the 215th meeting of the American Astronomical Society in

Washington, D.C. ) , image_skyline = , image_caption = Clockwise from top left: the Washington Monument and Lincoln Memorial on the National Mall, United States Capitol, Logan Circle, Jefferson Memorial, White House, Adams Morgan, ...

, along with planets around

Kepler-4 Kepler-4 is a sunlike star located about 1610 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 ...

, Kepler-6,

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 ...

, and

Kepler-8 Kepler-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, ...

. Kepler-5b's initial discovery by Kepler was re-examined by scientists at the

W.M. Keck Observatory The W. M. Keck Observatory is an astronomical observatory with two telescopes at an elevation of 4,145 meters (13,600 ft) near the summit of Mauna Kea in the U.S. state of Hawaii. Both telescopes have aperture primary mirrors, and when comp ...

Mauna Kea Mauna Kea ( or ; ; abbreviation for ''Mauna a Wākea''); is a dormant volcano on the island of Hawaii. Its peak is above sea level, making it the highest point in the state of Hawaii and second-highest peak of an island on Earth. The peak is ...

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

; the

McDonald Observatory McDonald Observatory is an astronomical observatory located near unincorporated community of Fort Davis in Jeff Davis County, Texas, United States. The facility is located on Mount Locke in the Davis Mountains of West Texas, with additional facil ...

in west

Texas Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...

; the Palomar and Lick Observatories in

California 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 ...

; the MMT, WIYN, and

Whipple Whipple may refer to: People *Whipple (surname) (including a list of people with the surname) *Whip Jones (1909–2001), American ski industry pioneer, founder, developer and original operator of the Aspen Highlands ski area in Aspen, Colorado * W ...

Observatories in

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

; and the

Roque de los Muchachos Observatory Roque de los Muchachos Observatory ( es, Observatorio del Roque de los Muchachos, ORM) is an astronomical observatory located in the municipality of Garafía on the island of La Palma in the Canary Islands, Spain. The observatory site is operated ...

in the

Canary Islands The Canary Islands (; es, Canarias, ), also known informally as the Canaries, are a Spanish autonomous community and archipelago in the Atlantic Ocean, in Macaronesia. At their closest point to the African mainland, they are west of Morocc ...

Characteristics

Kepler-5 is a sunlike star that is 1.374 (± 0.056) M_sun and 1.793 (± 0.053) R_sun, and is 137% the mass of and 179% the radius of the

. The star has a

of e/H0.04 (± 0.06), making it approximately as metal-rich as the Sun, therefore increasing the star's likelihood to have planets in orbit. Kepler-5 has 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 6297 (± 60) K, which is hotter than the Sun's effective temperature of 5778 K. Kepler-5 has an

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 li ...

of 13.4, and cannot be seen with the

naked eye Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying, light-collecting optical instrument, such as a telescope or microscope, or eye protection. Vision corrected to normal ...

Companion stars

A recent catalog of companions to Kepler stars determined from high-resolution imaging shows two companions to Kepler-5 at distances of 0.9 and 3.5

arc seconds A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of Angular unit, angular measurement equal to of one Degree (angle), degree. Since one degree is of a turn (geometry), turn (or complete rotat ...

. Whether these stars are physically bound to Kepler-5 or merely chance alignments of unrelated stars is unknown however recent studies have shown that 60 to 80% of companions within 1 arc second of Kepler stars are true binaries.

Planetary system

Kepler-5b is 2.111 M_J and 1.426 R_J. It is, thus, more than twice the mass of

, and slightly less than three halves of Jupiter's radius. Kepler-5b orbits its star every 3.5485 days, lying at approximately 0.0538 AU from Kepler-5. It is, thus, a

Hot Jupiter Hot Jupiters (sometimes called hot Saturns) are a class of gas giant exoplanets that are inferred to be physically similar to Jupiter but that have very short orbital periods (). The close proximity to their stars and high surface-atmosphere temp ...

, or a gas giant that orbits near to its host star. To compare,

Mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

orbits the sun at .3871 AU every 87.97 days. The planet's

eccentricity Eccentricity or eccentric may refer to: * Eccentricity (behavior), odd behavior on the part of a person, as opposed to being "normal" Mathematics, science and technology Mathematics * Off-center, in geometry * Eccentricity (graph theory) of a v ...

is assumed to be 0, which is the eccentricity for a circular orbit.

References

{{Stars of Cygnus Planetary systems with one confirmed planet Cygnus (constellation) 18 Planetary transit variables F-type subgiants

Nomenclature and history

Characteristics

Companion stars

Planetary system

See also

References