M33

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Telescope: Orion ED80 Camera: SBig ST-8 Filters: Clear Exposure: 7 minutes Temperature: -30 deg C Date: 26/8/2006 Software acquisition: acquired with ccdsoft Processing Software: Maxim DL, stacking 7 x 60 sec exposures dark subtracted, stretch 0.2, exp histogram. Where: Tenby Observatory, Coonabarabran Lat: 31 16 35.05 S, Long 149 11 33.99 E, Elevation 547metres

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Telescope: Orion ED80 Camera: Canon 300D Filters: N/A Exposure: Date: Dec/2005 Processing Software: Maxim DL, stretch 0.2, exp histogram. Where: Tenby Observatory, Coonabarabran Lat: 31 16 35.05 S, Long 149 11 33.99 E, Elevation 547metres

Common Name: M33 Other Names: Triangulum Galaxy, NGC 598 RA: 01 : 33.9 Dec +30 : 39 Constellation: Triangulum Distance: 3 million Light years Magnitude: 5.7 Notes: M33 was discovered by Hodierna before 1654 and is a member of our local group of galaxies. M33 is somewhat smaller than the Milky Way Galaxy but is a typical size for a spiral. M33 is approaching us at 182 km/s. The distance of M33 from M31 is about 750,000 light-years. Assuming the former value, its angular dimension of 73 arc minutes in major axis (about 2.5 times the Moon's diameter) corresponds to about 50,000 light-years, half the diameter of the Milky Way. However, the faintest outlayers seem to reach more far out, so that the true diameter may be at least 60,000 light-years. The mass of the Triangulum Galaxy has been estimated between 10 and 40 billion solar masses. The Triangulum galaxy M33 is of type Sc, and even a "late" representative of that type. The pronounced arms exhibit numerous reddish HII regions (including NGC 604), as well as blueish clouds of young stars. Baade has also discovered Population II stars, and globular clusters have been found. Although no supernovae have yet been detected in the Triangulum galaxy, several supernova remnants have, and were cartographed by radio astronomers with high acuracy. At least 112 variables have been discovered in M33, including 4 novae and about 25 Cepheids. A strong X-ray source is also situated in this galaxy. For the observer, this galaxy can be glanced with the naked eye under exceptionally good conditions; for most people, it is the most distant object visible to the naked eye It is outstanding in good binoculars, but as its considerable total brightness is distributed quite evenly over an area of nearly four times that covered by the full Moon, its surface brightness is extremely low. Therefore, it is difficult to impossible to view this galaxy in telescopes which do not allow low magnification - lowest is best for this object !