SkyEye

Triangulum

The Triangle

Abbreviation:Tri
Genitive:Trianguli
Origin:[antiquity]
Fully Visible:52°S – 90°N

The reason for the name is pretty self-explanatory! Some older star maps pair it with the now-obsolete constellation Triangulum Minus which sits nearby. It is somewhat larger than its southern counterpart, the constellation Triangulum Australe.

The constellation of Triangulum

Notable Features

Visible Named Stars
α Tri Mothallah This star sometimes appears as Caput Trianguli (from the Latin caput trianguli meaning 'the head of the triangle') in older star atlases and catalogues. It also appears as Metallah in Antonín Bečvář's Atlas of the Heavens — Ⅱ Catalogue 1950.0.
Other Interesting Stars
HAT‑P‑38 Horna Found somewhat south of the star γ Tri, this thirteenth-magnitude star is known to have at least one exoplanet.
Deep Sky Objects
M33 Triangulum Galaxy This is one of the largest members of the Local Group of galaxies. It is a spiral and it is just about possible to see it with the naked eye if skies are very dark. It is sometimes incorrectly called the Pinwheel Galaxy but that name properly belongs to a spiral galaxy in Ursa Major.