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Fornax

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Fornax is a prominent constellation located in the southern celestial hemisphere. Its name is the Latin word for a furnace. This name reflects the scientific tools once associated with the constellation. It is one of the 88 modern constellations recognized by astronomers. Fornax occupies an area of 398 square degrees. This makes it the 41st largest constellation in the night sky. It is located in the first quadrant of the southern hemisphere. Observers can see it at latitudes between +50° and -90° during December.

Constellation Fornax
Constellation Fornax

The constellation is surrounded by several other celestial patterns. Eridanus borders Fornax to the east, north, and south. To the north, west, and south, it is girded by Cetus, Sculptor, and Phoenix. The official boundaries were set by the Belgian astronomer Eugène Delporte in 1930. He defined the area using a polygon of eight segments. In the equatorial coordinate system, the right ascension lies between 3h 23m and 4h 48m. The declination ranges from −23.76° to −39.58°. The International Astronomical Union adopted the abbreviation "For" in 1922.

Sidney Hall - Urania's Mirror - Psalterium Georgii, Fluvius Eridanus, Cetus, Officina Sculptoris, Fornax Chemica, and Machina Electrica
Sidney Hall - Urania's Mirror - Psalterium Georgii, Fluvius Eridanus, Cetus, Officina Sculptoris, Fornax Chemica, and Machina Electrica

Stars within Fornax show incredible variety in size and behavior. The three brightest stars form a flattened triangle facing south. Alpha Fornacis is the brightest star with an apparent magnitude of 3.91. It is a binary star system located 46.4 light-years away. The primary star is a yellow-white subgiant that is 1.21 times as massive as the Sun. It has expanded to 1.9 times the solar radius. The secondary star is a blue straggler with 0.78 times the mass of the Sun. Beta Fornacis is a red clump giant star. It has swelled to 11 times the diameter of the Sun. Nu Fornacis is a blue giant star that is 245 times as luminous as the Sun. This star is an Alpha2 Canum Venaticorum variable. It varies in brightness over a period of 1.89 days.

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History shows how humans have mapped this part of the sky. French astronomer Nicolas Louis de Lacaille first described the constellation. He originally called it le Fourneau Chymique, or the Chemical Furnace. He did this after cataloguing nearly 10,000 southern stars at the Cape of Good Hope. He spent two years observing these stars before 1756. Lacaille devised fourteen new constellations to fill uncharted southern regions. Most of these names honored scientific instruments from the Age of Enlightenment. He later Latinized the name to Fornax Chimiae on his 1763 chart.

Constellation Fornax
Constellation Fornax

Fornax is also a place to find planets and small stars. Astronomers have found six star systems in Fornax that have exoplanets. For example, the star HR 858 has at least three exoplanets. These were seen using the transit method by the Transiting Exoplanet Survey Satellite. Lambda2 Fornacis has a planet about as massive as Neptune. The star HD 20868 has a planet double the mass of Jupiter. There are also very small objects like brown dwarfs. LP 944-20 is a brown dwarf with about 7% the mass of the Sun. Another object, 2MASS 0243-2453, has a surface temperature between 1040 and 1100 K.

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The Fornax Cluster is a massive collection of galaxies. It is the second richest galaxy cluster within 100 million light-years. It is part of a much larger structure called the Fornax Wall. One major member is NGC 1399, a large elliptical galaxy. It is 66 million light-years away and 130,000 light-years in diameter. This galaxy is slightly larger than our Milky Way. Another notable object is NGC 1316, a radio galaxy. It is a large elliptical galaxy with dust lanes near its core. These lanes suggest it recently merged with a small spiral galaxy.

Galaxies in the Fornax Cluster
Galaxies in the Fornax Cluster

Deep-space objects in Fornax help us understand the universe. The Hubble Space Telescope's Ultra-Deep Field is located within this constellation. This allows scientists to see very distant parts of space. The Fornax Dwarf galaxy is another important feature. It is a small satellite galaxy of the Milky Way. It is located about 500,000 light-years from Earth. This galaxy was once destroyed by the Milky Way 6 billion years ago. Its remnants are seen in the Helmi stream. Studying these objects helps astronomers learn how galaxies grow and change over time.

Galaxies in the Fornax Cluster
Galaxies in the Fornax Cluster
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File:Sidney Hall - Urania's Mirror - Psalterium Georgii, Fluvius Eridanus, Cetus, Officina Sculptoris, Fornax Chemica, and Machina Electrica.jpg
Sidney Hall - Urania's Mirror -...
File:Constellation Fornax.jpg
Constellation Fornax.jpg
File:Heic1425a.jpg
Heic1425a.jpg
File:Galaxies in the Fornax Cluster.jpg
Galaxies in the Fornax Cluster.jpg
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