I have planned and scheduled a mosaic of 2 x 2 panels, each had a FOV of 36 arc minutes.

Imaged from 30 September until 31 October 2014.

Used SLOOH 20" robotic telescope on Teide, Canary Island.

SLOOH logo must be added to any original or processed image according to SLOOH terms&conditions.

I have added a monochrome version which is another great look on this beauty.

Another version is with annotation of identified NGC and IC catalog numbers

The following are interesting facts - mostly taken from wikipedia and other sources:

M33 is one of the most distant permanent objects that can be viewed with the naked eye (under good viewing conditions as it is a diffuse object, and is one of the critical sky marks of the Bortle Dark-Sky Scale).

M33 has a diameter of about 500 kly and contains approx. 40 billion stars (compared to 400 billion for the Milky Way, and 1 trillion (1000 billion) stars for Andromeda).

The combined mass of all baryonic matter in the galaxy may be 10 billion solar masses. The contribution of the dark matter component out to a radius of 55 kly is equivalent to about 50 billion solar masses.

Estimates of the distance to the Triangulum galaxy range from 2.38 to 3.07 mly, making it slightly more distant than the Andromeda Galaxy.

The Pinwheel 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 galaxies. On the linked page you can see a clickable map of the galaxies. This is an isolated galaxy and there are no indications of recent mergers or interactions with other galaxies.

M33 is moving towards Andromeda and suggesting it may be a satellite of the larger galaxy. Clumpy stream of hydrogen gas linking the Andromeda Galaxy with Triangulum evidence suggests that the two may have tidally interacted in the past. The Pisces Dwarf (LGS 3), one of the small Local Group member galaxies, could be a satellite galaxy of either Andromeda or Triangulum.

Structure classification SA(s)cd: The S prefix for a spiral galaxy, the A is assigned when the galactic nucleus lacks a bar-shaped structure, the (s) notation is used when the spiral arms emerge directly from the nucleus or central bar, the cd suffix represents a stage along the spiral sequence that describes the openness of the arms, the cd indicates relatively loosely wound arms.

This galaxy has an inclination of 54° to the line of sight from the Earth, allowing the structure to be examined without significant obstruction by gas and dust.

The nucleus does not appear to contain a supermassive black hole, as an upper limit of 3,000 solar masses is placed on the mass of a central black hole. The inner part of the galaxy has two luminous spiral arms, along with multiple spurs that connect the inner to the outer spiral features.

The total integrated rate of star formation in the Triangulum galaxy is about 0.45 ± 0.1 solar masses per year.

About 54 globular clusters have been identified in this galaxy, but the actual number may be 122 or more.

The Pinwheel Galaxy is a nickname shared with M101 and few other galaxies.

Suggested future scenarios for M33 include being torn apart and absorbed by Andromeda, fueling the latter with hydrogen to form new stars; eventually exhausting all of its gas, and thus the ability to form new stars; or participating in the collision between the Milky Way and M31, most likely ending up orbiting the merger product of the latter two galaxies and fusing with it much later. Two other possibilities are a collision with the Milky Way before Andromeda arrives or an ejection out of the Local Group.

H II regions

Using infrared observations from the Spitzer Space Telescope, a total of 515 discrete candidate sources of 24 μm emission within the Triangulum galaxy have been catalogued as of 2007. The brightest sources lie within the central region of the galaxy and along the spiral arms.

Many of the emission sources are associated with H II regions of star formation. The 4 brightest regions designated under NGC catalog are associated with molecular clouds containing between 120,000 and 400,000 solar masses. You can find further information on the identified 5 NGC and 10 IC objects on Steve Gottlieb's page (http://astronomy-mall.com/Adventures.In.Deep.Space/M33.HII-Star.Clouds.html) and Mr. Seligman's Finding Chart for IC / NGC Objects in M33 (http://cseligman.com/text/atlas/ic1.htm#ic130), where you can read further details about each.

Supernova discoveries: none

The estimated rate of supernova explosions in the Triangulum Galaxy is 0.06 Type Ia and 0.62 Type Ib/Type II per century. As of 2008, a total of 100 supernova remnants have been identified in the galaxy, and a majority of the remnants lie in the southern half of the spiral galaxy.

Discovery: M33 was probably discovered by the Italian astronomer Giovanni Battista Hodierna before 1654

The galaxy was independently discovered by Charles Messier on the night of 25 - 26 August 1764.

William Herschel also catalogued the Triangulum Galaxy's brightest and largest H II region (diffuse emission nebula containing ionized hydrogen) as H III.150 separately from the galaxy itself on 11 September 1784, which eventually obtained NGC number 604.