KOI-81
Encyclopedia
KOI-81 is an eclipsing binary star in the constellation of Cygnus
. The primary star is a late B-type or early A-type main sequence star with a temperature of 10000 K (9,726.9 °C; 17,540.3 °F). It lies in the field of view of the Kepler Mission
and was determined to have an object in orbit around it which is smaller and hotter than the main star.
and came to attention because of its small size and high temperature of 17000 K (16,726.9 °C; 30,140.3 °F). The orbit of KOI-81b around the main star takes 23.8776 days to complete. Analysis of relativistic effects in the Kepler light curve suggests that it is a low-mass white dwarf star of approximately 0.3 solar mass
es, produced by a previous stage of mass transfer
during the object's giant phase
.
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 primary star is a late B-type or early A-type main sequence star with a temperature of 10000 K (9,726.9 °C; 17,540.3 °F). It lies in 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...
and was determined to have an object in orbit around it which is smaller and hotter than the main star.
KOI-81b
KOI-81b is a hot compact object orbiting KOI-81. It was discovered in 2010 by 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...
and came to attention because of its small size and high temperature of 17000 K (16,726.9 °C; 30,140.3 °F). The orbit of KOI-81b around the main star takes 23.8776 days to complete. Analysis of relativistic effects in the Kepler light curve suggests that it is a low-mass white dwarf star of approximately 0.3 solar mass
Solar mass
The solar mass , , is a standard unit of mass in astronomy, used to indicate the masses of other stars and galaxies...
es, produced by a previous stage of mass transfer
Mass transfer
Mass transfer is the net movement of mass from one location, usually meaning a stream, phase, fraction or component, to another. Mass transfer occurs in many processes, such as absorption, evaporation, adsorption, drying, precipitation, membrane filtration, and distillation. Mass transfer is used...
during the object's giant phase
Giant star
A giant star is a star with substantially larger radius and luminosity than a main sequence star of the same surface temperature. Typically, giant stars have radii between 10 and 100 solar radii and luminosities between 10 and 1,000 times that of the Sun. Stars still more luminous than giants are...
.
See also
- KOI-74KOI-74KOI-74 is an eclipsing binary star in the constellation of Cygnus. The primary star is an A-type main sequence star with a temperature of . It lies in the field of view of the Kepler Mission and was determined to have a companion object in orbit around it which is smaller and hotter than the main...
, a similar system also discovered by the Kepler Mission. - Kepler Object of InterestKepler Object of InterestA Kepler Object of Interest is a star observed by the Kepler spacecraft which is suspected of hosting one or more transiting planets. KOIs come from a master list of 150,000 stars which itself is generated from the Kepler Input Catalog . A KOI shows a periodic dimming, indicative of an unseen...
, stars observed to have transits by the Kepler Mission