Although above the horizon and hence visible to the Ancient Greeks, Antlia's stars were too faint to have been included in any ancient constellations. The stars that now comprise Antlia lay within an area of the sky covered by the ancient constellation Argo Navis, the Ship of the Argonauts, which due to its immense size was split into several smaller constellations by Lacaille in 1763. Ridpath reports that due to their faintness, the stars of Antlia did not make up part of the classical depiction of Argo Navis.
In non-Western astronomy
Chinese astronomers were able to view what is modern Antlia from their latitudes, and incorporated its stars into two different constellations. Several stars in the southern part of Antlia were a portion of "Dong'ou", which represented an area in southern China. Furthermore, Epsilon, Eta, and Theta Antliae were incorporated into the celestial temple, which also contained stars from modern Pyxis.
Covering 238.9 square degrees and hence 0.579% of the sky, Antlia ranks 62nd of the 88 modern constellations by area. Its position in the Southern Celestial Hemisphere means that the whole constellation is visible to observers south of 49°N.[b]Hydra the sea snake runs along the length of its northern border, while Pyxis the compass, Vela the sails, and Centaurus the centaur line it to the west, south and east respectively. The three-letter abbreviation for the constellation, as adopted by the International Astronomical Union, is Ant. The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930,[c] are defined by a polygon of twelve segments (illustrated in infobox at top-right). In the equatorial coordinate system, the right ascension coordinates of these borders lie between 09h 26.5m and 11h 05.6m, while the declination coordinates are between −24.54° and −40.42°.
Lacaille gave nine stars Bayer designations, labelling them Alpha through to Theta, including two stars next to each other as Zeta. Gould later added a tenth, Iota Antliae. Beta and Gamma Antliae (now HR 4339 and HD 90156) ended up in the neighbouring constellation Hydra once the constellation boundaries were delineated in 1930. Within the constellation's borders, there are 42 stars brighter than or equal to apparent magnitude 6.5.[d]
The constellation's two brightest stars—Alpha and Epsilon Antliae—shine with a reddish tinge. Alpha is an orange giant of spectral typeK4III that is a suspected variable star, ranging between apparent magnitudes 4.22 and 4.29. It is located 320 ± 10 light-years away from Earth. Estimated to be shining with around 480 to 555 times the luminosity of the Sun, it is most likely an ageing star that is brightening and on its way to becoming a Mira variable star, having converted all its core fuel into carbon. Located 590 ± 30 light-years from Earth, Epsilon Antliae is an evolved orange giant star of spectral type K3 IIIa, that has swollen to have a diameter about 69 times that of the Sun, and a luminosity of around 1279 Suns. It is slightly variable. At the other end of Antlia, Iota Antliae is likewise an orange giant of spectral type K1 III. It is 202 ± 2 light-years distant.
HD 93083 is an orange dwarf star of spectral type K3V that is smaller and cooler than the Sun. It has a planet that was discovered by the radial velocity method with the HARPS spectrograph in 2005. About as massive as Saturn, the planet orbits its star with a period of 143 days at a mean distance of 0.477 AU.WASP-66 is a sunlike star of spectral type F4V. A planet with 2.3 times the mass of Jupiter orbits it every 4 days, discovered by the transit method in 2012.DEN 1048-3956 is a brown dwarf of spectral type M8 located around 13 light-years distant from Earth. At magnitude 17 it is much too faint to be seen with the unaided eye. It has a surface temperature of about 2500 K. Two powerful flares lasting 4–5 minutes each were detected in 2002.2MASS 0939-2448 is a system of two cool and faint brown dwarfs, probably with effective temperatures of about 500 and 700 K and masses of about 25 and 40 times that of Jupiter, though it is also possible that both objects have temperatures of 600 K and 30 Jupiter masses.
Galaxy ESO 376-16 is located nearly 23 million light-years from Earth.
^Although parts of the constellation technically rise above the horizon to observers between the 49°N and 65°N, stars within a few degrees of the horizon are to all intents and purposes unobservable.
^Delporte had proposed standardising the constellation boundaries to the International Astronomical Union, who had agreed and gave him the lead role
^Objects of magnitude 6.5 are among the faintest visible to the unaided eye in suburban-rural transition night skies.
^Bakich, Michael E. (1995). The Cambridge Guide to the Constellations. Cambridge, United Kingdom: Cambridge University Press. ISBN978-0-521-44921-2.
^Hellier, Coel; Anderson, D. R.; Collier Cameron, A.; Doyle, A. P.; Fumel, A.; Gillon, M.; Jehin, E.; Lendl, M.; Maxted, P. F. L.; Pepe, F.; Pollacco, D.; Queloz, D.; Ségransan, D.; Smalley, B.; Smith, A. M. S.; Southworth, J.; Triaud, A. H. M. J.; Udry, S.; West, R. G. (2012). "Seven transiting hot Jupiters from WASP-South, Euler and TRAPPIST: WASP-47b, WASP-55b, WASP-61b, WASP-62b, WASP-63b, WASP-66b and WASP-67b". Monthly Notices of the Royal Astronomical Society. 426 (1): 439–50. arXiv:1204.5095. Bibcode:2012MNRAS.426..739H. doi:10.1111/j.1365-2966.2012.21780.x.
^Torrealba, G.; Belokurov, V.; Koposov, S. E.; Li, T. S.; Walker, M. G.; Sanders, J. L.; Geringer-Sameth, A.; Zucker, D. B.; Kuehn, K.; Evans, N. W.; Dehnen, W. (2018). "The hidden giant: Discovery of an enormous Galactic dwarf satellite in Gaia DR2". arXiv:1811.04082 [astro-ph.GA].
Wagman, Morton (2003). Lost Stars: Lost, Missing and Troublesome Stars from the Catalogues of Johannes Bayer, Nicholas Louis de Lacaille, John Flamsteed, and Sundry Others. Blacksburg, VA: The McDonald & Woodward Publishing Company. ISBN978-0-939923-78-6.