Messier 33, the Triangulum Galaxy, is a face-on spiral galaxy in the constellation Triangulum and the third-largest member of the Local Group after the Milky Way and Andromeda.

Click the image to zoom in (4 steps), then again for full view · hover to see it annotated · open full resolutionAnnotated image · click to zoom in (4 steps), then again for full view · open full resolutionSky location chart · click to zoom in (4 steps), then again for full view · open full resolution

Messier 33, the Triangulum Galaxy, is a face-on spiral galaxy in the constellation Triangulum and the third-largest member of the Local Group after the Milky Way and Andromeda. It lies approximately 2.7 million light-years away, with a true diameter of roughly 60,000 light-years. Unlike the more dramatic M31, M33 has a comparatively low surface brightness, making it more challenging to image well from light-polluted skies despite its relatively large apparent size. Its loosely wound spiral arms host numerous star-forming HII regions, most notably NGC 604, one of the largest known star-forming regions in the Local Group. M33 rewards long, dark-sky exposures that bring out its faint spiral structure and pink-tinged nebular knots.

[Source: Wikipedia, en.wikipedia.org/wiki/Triangulum_Galaxy]

Annotated Image

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Sky Location

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Image Details

Moon Phase:Waxing Crescent
Camera:ToupTek ATR2600C
Optics:Skywatcher Esprit 120ED, 840 mm focal length, f/7 (120 mm aperture, APO triplet)
Date:2025-09-24

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