WASP-121, also known as CD-38 3220 and formally named Dilmun, is a

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

10.4

star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

located approximately away 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 first constellati ...

Puppis Puppis ("poop deck, stern") is a constellation in the southern sky. It was originally part of the Former constellations, traditional constellation of Argo Navis (the ship of Jason and the Argonauts), which was divided into three parts, the other ...

. WASP-121 has a

mass Mass is an Intrinsic and extrinsic properties, intrinsic property of a physical body, body. It was traditionally believed to be related to the physical quantity, quantity of matter in a body, until the discovery of the atom and particle physi ...

and

radius In classical geometry, a radius (: radii or radiuses) of a circle or sphere is any of the line segments from its Centre (geometry), center to its perimeter, and in more modern usage, it is also their length. The radius of a regular polygon is th ...

similar to the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

's. It hosts one 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 ...

. The star, although metal-rich in terms of overall contents of heavy elements, is depleted of carbon. The carbon to oxygen molar ratio of 0.23 for WASP-121 is well below the solar ratio of 0.55.

Nomenclature

The designation ''WASP-121'' indicates that this was the 121st star found to have a planet by the

Wide Angle Search for Planets WASP or Wide Angle Search for Planets is an international consortium of several academic organisations performing an ultra-wide angle search for exoplanets using transit photometry. The array of robotic telescopes aims to Astronomical survey, s ...

. In August 2022, this planetary system was included among 20 systems to be named by the third

NameExoWorlds NameExoWorlds (also known as IAU NameExoWorlds) were various projects managed by the International Astronomical Union (I.A.U.) to encourage names to be submitted for astronomical objects, notably exoplanets. The accepted names would later be cons ...

project. The approved names, proposed by a team from

Bahrain Bahrain, officially the Kingdom of Bahrain, is an island country in West Asia. Situated on the Persian Gulf, it comprises a small archipelago of 50 natural islands and an additional 33 artificial islands, centered on Bahrain Island, which mak ...

, were announced in June 2023. WASP-121 is named Dilmun after the

ancient civilization A civilization (also spelled civilisation in British English) is any complex society characterized by the development of the state, social stratification, urbanization, and symbolic systems of communication beyond signed or spoken langua ...

, and its planet is named Tylos after the ancient Greek name for Bahrain.

Planetary system

In 2015, the

WASP-121b was discovered orbiting WASP-121 by the

transit method Methods of detecting exoplanets usually rely on indirect strategies – that is, they do not directly image the planet but deduce its existence from another signal. Any planet is an extremely faint light source compared to its parent star. For e ...

. WASP-121b is 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 ...

with a mass about 1.18 times that of Jupiter and a radius about 1.81 times that of Jupiter. The exoplanet orbits WASP-121, its host star, every 1.27 days. Hot water molecules have been found in the

stratosphere The stratosphere () is the second-lowest layer of the atmosphere of Earth, located above the troposphere and below the mesosphere. The stratosphere is composed of stratified temperature zones, with the warmer layers of air located higher ...

of WASP-121b (i.e., the

atmospheric An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosphere ...

layer in which temperatures increase as the altitude increases).

Gallery

PIA22565-Exoplanet-WASP121b-ComputerSimViews-20180809.jpg, HD189733b.jpg, An artist's impression of a

planet

References

External links

SuperWASP Wide Angle Search for Planets: The Planets

{{DEFAULTSORT:WASP-121 Puppis Planetary systems with one confirmed planet Planetary transit variables F-type main-sequence stars J07102406-3905506 CD-38 3220 0495

121 121 may refer to: *121 (number), a natural number * AD 121, a year in the 2nd century AD * 121 BC, a year in the 2nd century BC * 121 (Eagle) Sqn, a Royal Air Force aircraft squadron that during the Second World War was one of the three Eagle Squa ...

Dilmun Dilmun, or Telmun, ( Sumerian: ,Transliteration: Similar text: later 𒉌𒌇(𒆠), NI.TUKki = dilmunki; ) was an ancient East Semitic–speaking civilization in Eastern Arabia mentioned from the 3rd millennium BC onwards. Based on contextual ...

Nomenclature

Planetary system

Gallery

See also

References

External links