Transit Date of principal star:
20 October

Triangulum lies just to the north of Aries. In antiquity its distinctive shape of three stars was called Deltoton.

Despite its small size it contains one of Messier's objects, a faint face-on spiral galaxy (see below). Triangulum's stars are even fainter than Aries'.

Double stars:

6 Trianguli [sometimes listed as iota Tri] is an attractive binary with colour contrast, yellow and blue: 5.3, 6.9; PA 71 and separation 3.9".

Variable stars:

R Trianguli is a long-period variable ranging from 5.4 to 12.6 every 266.9 days. In 2000 the maximum should occur around the first or second week of December.

Deep Sky Objects:

M33 (NGC 598) is a very large but quite faint face-on spiral galaxy sometimes known under the name "Pinwheel Galaxy" since it is said to be slowly rotating in a clockwise motion, making a complete turn probaby every 200 million years.

It's seventeen arc minutes west of alpha Trianguli and one degree north; or just about midpoint between alpha Arietis and beta Andromedae (slightly closer to the latter).

The galaxy is estimated to be from 2.5 to 3.5 million light years away. Low power scopes, or even binoculars, work best.

For a little more on Triangulum visit the Binocular Section.

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