An Etymological Dictionary of Astronomy and Astrophysics
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The Air Pump. A faint → constellation in the → southern hemisphere, at → right ascensionα ~ 10h, → declinationδ ~ -35 deg. Abbreviation: Ant; genitive form: Antliae. Antlia is one of the smaller constellations in the sky, occupying an area of 239 square degrees. It is located in the second quadrant of the southern hemisphere and can be seen at latitudes between +45° and -90°. The neighboring constellations are → Centaurus, → Hydra, → Pyxis, and → Vela. Antlia does not have any stars brighter than magnitude 3.00. It contains two stars located within 10 → parsecs of Earth. The brightest star in Antlia is Alpha Antliae. The nearest star in Antlia, DEN 1048-3956, is a → brown dwarf brown dwarf only ~ 4 parsecs, 13.15 → light-years distant from Earth. Notable deep sky objects in Antlia include the → Antlia dwarf Galaxy, → Antlia 2, the Antlia Cluster of Galaxies, and the unbarred → spiral galaxy NGC 2997.

L. antlia "pump," from Gk. antlia "ship's hold, bilge water," from antlos.

Tolombé "pump," from Turkish tulumba "pump," from It. tromba.

A Milky-Way satellite in the constellation → Antlia. Antlia. It was originally detected in Gaia DR2 data using a combination of → RR Lyrae, → proper motions, → parallaxes and shallow → broad-band photometry. Antlia 2 is located behind the → Galactic disk at a latitude of b ~ 11° and spans 1.26 degrees, which corresponds to ~ 2.9 kpc at its distance of 130 kpc. While similar in extent to the → Large Magellanic Cloud, Antlia 2 is orders of magnitude fainter with M_V = -8.5 mag, making it by far the lowest surface brightness system known (at 32.3 mag/arcsec²), ~ 100 times more diffuse than the so-called ultra diffuse galaxies. The dwarf's systemic velocity is 290.9 ± 0.5 km s^-1, its velocity dispersion, 5.7 ± 1.1 km s^-1, and mean → metallicity, [Fe/H]= -1.4 (Torrealba et al., 2018, arXiv:1811.04082).

→ Antlia.

A → dwarf spheroidal galaxy located about 4.3 million → light-years from. Earth. It is a very faint object, with an apparent magnitude of 16.2. The galaxy was not discovered until 1997. (PGC 29194) The Antlia Dwarf lies on the outer rim of the Local Group of galaxies, possibly even beyond it, and there is evidence suggesting that it is tidally interacting with another small galaxy, NGC 3109, in the → Hydra constellation.

→ Antlia; → dwarf.

A → carbon star of the → asymptotic giant branch type located in the constellation of → Antlia. Its other designations are HIP 51821 (→ Hipparcos Star Catalogue), HD 91793, and HR 4153. U Antliae is an → irregular variable that changes its → visual magnitude between 5.27 and 6.04. About 850 → light-years from Earth, it shines with a → luminosity approximately 8,000 times that of the → solar luminosity and has a → surface temperature 2,800 K. It is surrounded by a complex structure of dust shells. Around 2,700 years ago, U Antliae went through a short period of rapid → mass loss. During this period of only a few hundred years, the material making up the shell seen in the → Atacama Large Millimeter Array (ALMA) data was ejected at high speed (Kerschbaum et al., 2017, A&A 605, A116, arXiv:1708.02915).

U, according to → variable star designation; → Antlia.