The closest spiral is the Andromeda Galaxy, at a distance of 2.5 million light-years. The Triangulum Galaxy, also known as Messier 33 (M33), is a spiral galaxy in Triangulum constellation..

John Flamsteed added Eta, Iota and four Roman letters; of these, only Iota is still used as the others were dropped in subsequent catalogues and star charts. With a diameter of about 60,000 light-years, the Triangulum galaxy is the third largest member of the Local Group of galaxies, roughly 60% the size of the Milky Way. Areas … The Triangulum Galaxy (M33) that is about 3 million light-years away from Earth. The Pisces Dwarf, another galaxy in the Local Group, is located 913,000 light years from both galaxies and could be a satellite galaxy of either Triangulum or Andromeda Galaxy.

Triangulum Galaxy Shows Stunning Face in Detailed Hubble Portrait. The Triangulum Galaxy is the smallest spiral galaxy in the Local Group and is also its only unbarred spiral galaxy. Guiding camera:ZWO ASI290MC. Technical card Imaging telescope or lens:SKYWATCHER 200/1000. The Triangulum Galaxy is not only surpassed in size by the other two spirals, but by the multitude of stars they contain.

Guiding telescope or lens:Orion 80mm f/11. Triangulum may be home to 40 billion stars, compared to 400 billion for the Milky Way, and 1 trillion stars for Andromeda Galaxy.
Among its most distinctive features are ionized hydrogen clouds, which are massive regions of starbirth. It is catalogued as Messier 33 or NGC 598, and is sometimes informally referred to as the '''Pinwheel Galaxy''', a nickname it shares with M101.

NGC 604 contains about 200 Type II supernova candidates. The Triangulum Galaxy has at least an order of magnitude less stars than the Milky Way and two orders of magnitude less than Andromeda. Among its most distinctive features are ionized hydrogen clouds, which are massive regions of starbirth. Triangulum Galaxy – Messier 33 (NGC 598) … The core of the Triangulum Galaxy is a nebula – a cloud of gas and dust – called an HII region. It lies 3 million light-years away, in the constellation Triangulum. NASA's Hubble Space Telescope brings the vastness of space into perspective in this mosaic image of the Triangulum galaxy (M33), our neighbor in a collection of dozens of galaxies called the Local Group. This suggests that the two galaxies have tidally interacted in the past. The Triangulum Galaxy is formally described as a spiral galaxy with a weak (or possibly no) central bar and its loosely wound arms emanate from the galactic core. The Triangulum Galaxy (M33) that is about 3 million light-years away from Earth. The estimated age of the cluster is 3.5 million years. Mount:Skywatcher NEQ5. The Triangulum Galaxy captured during the Black Forest Star Party.

The Triangulum Galaxy is the third-largest member of the Local Group of galaxies, which includes the Milky Way, the Andromeda Galaxy and about 44 other smaller galax… The NASA/ESA Hubble Space Telescope has captured the most detailed image yet of a close neighbour of the Milky Way — the Triangulum Galaxy, a spiral galaxy located at a distance of only three million light-years. And, in a study that pushes the limits of observations currently possible from Earth, a team of NASA and European scientists recorded the "fingerprints" of mystery molecules in the Triangulum Galaxy, as well as the Andromeda Galaxy. Bayer catalogued five stars in the constellation, giving them the Bayer designations Alpha to Epsilon. It lies at an approximate distance of 3 million light years from Earth and has a diameter of about 50,000 light years. The Triangulum Galaxy is located nearly 3 million light years from Earth.

It may be a gravitationally bound companion of the Andromeda Galaxy. The galaxy’s designation in the New General Catalogue is NGC 598.

A stream of hydrogen gas linking Triangulum to the Andromeda Galaxy was discovered in 2004 and confirmed in 2011.

Messier 33 can be seen visually with the naked eye under exceptionally good seeing conditions with no light pollution. The Triangulum Galaxy was independently discovered by Charles Messier in 1764 and was later published as object number 33 in his Catalog of Nebulae and Star Clusters. It is believed that the Triangulum galaxy has had past interactions with the Andromeda galaxy between 2 to 8 billion years ago, and is expected to have another, more violent interaction with its astronomical neighbour in another 2.5 billion years. Triangulum is a galaxy that despite its name is not a triangle, and is the third largest object in the Local Group, losing to Andromeda Galaxy and Milky Way. The Triangulum Galaxy is a spiral galaxy approximately 3 million light-years (ly) from Earth in the constellation Triangulum. Flamsteed gave 16 stars Flamsteed designations, of which numbers 1 and 16 are not used—1's coordinates were in error as there was no star present at the location that corresponds to any star in his Catalogus Britannicus; Baily presumed that the coordinates …

The Triangulum Galaxy (M33) is a spiral galaxy in the constellation Triangulum, that is believed to be a satellite of the Andromeda Galaxy.