Triangulum Galaxy
About this celestial object
A six-frame stack probes the expansive Triangulum Galaxy.
This face-on spiral is large but low in contrast; under dark skies it can be sensed in binoculars.
The minimal total time shows mainly the core region; H II regions and outer arms require longer exposures.
A 250 mm focal length frames the galaxy well without isolating fine detail.
Image and observation
Catalogue: M 33
Capture date: 2026-08-08
Total exposure: 13300 s
Imaging and processing: Ulrich Schwarz · Vespera Pro
Read the sky journey
Welcome to a journey through M33, the Triangulum Galaxy. Our view leads into the small northern constellation Triangulum and toward one of the Milky Way's nearest major neighbours in the Local Group. Its light takes about 2.7 million years to reach us. Because we see its disk at a comparatively modest inclination, this image reveals open spiral arms, dark dust and numerous bright regions where new stars are still forming today.
Dreiecksgalaxie
M33, also catalogued as NGC 598, is a spiral galaxy in the Local Group about 2.7 million light-years away. At more than 50,000 light-years across, it is smaller than both the Milky Way and the Andromeda Galaxy.
Its low surface brightness makes it a challenging target despite its apparent size. In this image, young blue stars and reddish clouds of ionised hydrogen trace its open spiral arms.
NGC 604
NGC 604 is the most luminous star-forming region in M33 and one of the largest H II regions in the Local Group. It lies in a spiral arm northeast of the galactic centre and appears as a distinct bright knot even in this wide view.
The nebula spans nearly 1,500 light-years. Ultraviolet radiation from many young, hot and massive stars ionises the surrounding gas; arcs, filaments and cavities record the effects of radiation and stellar winds within the complex.
NGC 595
NGC 595 is the second most luminous H II region in M33 after NGC 604. It lies closer to the galaxy's centre and marks another zone of intense star formation in a spiral arm.
Multiwavelength observations reveal a shell-like structure: young stars lie farther inside, ionised hydrogen and warm dust follow outside, and molecular gas sits slightly farther toward the edge. On this small scale we can see how stars reshape their birth cloud.
NGC 592
NGC 592 is a giant H II region in the outer part of one of M33's spiral arms. It is markedly less luminous than NGC 604, yet contains a substantial population of young, massive stars.
Some are rare Wolf–Rayet stars in a brief, energetic stage of evolution. Their intense radiation and fast stellar winds help ionise and sculpt the gas throughout the region.
NGC 588
NGC 588 is another giant H II region in M33 and the outermost stop on this journey. Its position away from the bright centre helps the glowing gas cloud stand out as a distinct knot in the spiral arm.
Hubble observations reveal young massive stars and Wolf–Rayet stars here as well. The region has a pronounced H-alpha shell: hot stars excite the hydrogen gas, while dust and molecular material trace its outer structures.