Pr0211 (sometimes written Pr 0211, also 2MASS J08421149+1916373) is a

Sun-like Solar-type stars, solar analogs (also analogues), and solar twins are stars that are particularly similar to the Sun. The stellar classification is a hierarchy with solar twin being most like the Sun followed by solar analog and then solar-typ ...

late G or early K-type main-sequence star in the

Beehive Cluster The Beehive Cluster (also known as Praesepe (Latin for "manger", "cot" or "crib"), M44, NGC 2632, or Cr 189), is an open cluster in the constellation Cancer. One of the nearest open clusters to Earth, it contains a larger population of stars tha ...

, or Praesepe, located 600

light-year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astr ...

s away in the constellation

Cancer Cancer is a group of diseases involving Cell growth#Disorders, abnormal cell growth with the potential to Invasion (cancer), invade or Metastasis, spread to other parts of the body. These contrast with benign tumors, which do not spread. Po ...

. It is rotationally variable and has a rotation period of 7.97 days, with its spin axis at an inclination of to the plane of the sky. Pr0211 hosts two known

exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first confirmed detection of an exoplanet was in 1992 around a pulsar, and the first detection around a main-sequence star was in 1995. A different planet, first det ...

s, and was the first multi-planet system to be discovered in an

open cluster An open cluster is a type of star cluster made of tens to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and ...

. Pr0211 forms a

double star In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. This occurs because the pair either forms a binary star (i.e. a ...

system with a

K-type main-sequence star A K-type main-sequence star, also referred to as a K-type dwarf, or orange dwarf, is a main-sequence (hydrogen-burning) star of spectral type K and luminosity class V. These stars are intermediate in size between red M-type main-sequence stars ...

known as NGC 2632 JC 280 or 2MASS J08421285+1916040. Although the stars share a similar distance and

common proper motion This glossary of astronomy is a list of definitions of terms and concepts relevant to astronomy and cosmology, their sub-disciplines, and related fields. Astronomy is concerned with the study of astronomical object, celestial objects and phenomena ...

, their relative space velocity appears to be high enough that the pair are not gravitationally bound.

Planetary system

Pr0211 b is a

gas giant A gas giant is a giant planet composed mainly of hydrogen and helium. Jupiter and Saturn are the gas giants of the Solar System. The term "gas giant" was originally synonymous with "giant planet". However, in the 1990s, it became known that Uranu ...

exoplanet, specifically 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 (i.e. Jupiter analogue, Jupiter analogues) but that have very short orbital periods (). The close proximity to t ...

, orbiting around Pr0211. Pr0211 b along with Pr0201 b are notable for being the first exoplanets discovered in the

. Pr0211 b and Pr0201 b were discovered in 2012 by Sam Quinn and his colleagues while observing 53 stars in the Beehive Cluster using the telescope at the

University of Georgia The University of Georgia (UGA or Georgia) is a Public university, public Land-grant university, land-grant research university with its main campus in Athens, Georgia, United States. Chartered in 1785, it is the oldest public university in th ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. Pr0211 c is a gas giant exoplanet orbiting around Pr0211. Pr0211 c was discovered in 2016 by Luca Malavolta and his colleagues while observing its host star with the HARPS-N spectrograph on the Italian Telescopio Nazionale Galileo (TNG) in

La Palma La Palma (, ), also known as ''La isla bonita'' () and historically San Miguel de La Palma, is the most northwesterly island of the Canary Islands, a Spanish autonomous community and archipelago in Macaronesia in the North Atlantic Ocean. La Pa ...

, and the Tillinghast Reflector Echelle Spectrograph (TRES) mounted at the telescope at the

in the

References

{{Cancer (constellation) Cancer (constellation) K-type main-sequence stars Planetary systems with two confirmed planets J08421149+1916373 Binary stars 175291727