PsA meaning in Academic & Science ?

Piscis Austrinus is a constellation in the southern celestial hemisphere. The name is Latin for "the southern fish", in contrast with the larger constellation Pisces, which represents a pair of fishes. Before the 20th century, it was also known as Piscis Notius. Piscis Austrinus was one of the 48 constellations listed by the 2nd-century astronomer Ptolemy, and it remains one of the 88 modern constellations. The stars of the modern constellation Grus once formed the "tail" of Piscis Austrinus. In 1597 (or 1598), Petrus Plancius carved out a separate constellation and named it after the crane.

Its only star brighter than 4th magnitude is Fomalhaut, the 18th-brightest star in the night sky. Surrounded by a circumstellar disk, it was announced as having a planet in 2008, though this discovery has been challenged. Lacaille 9352 is the brightest red dwarf star in the night sky; two super-Earths were discovered to be orbiting it in 2020. The BL Lacertae object PKS 2155-304 is one of the brightest blazars in the sky.