MEET ONE OF YOUR CLOSEST NEIGHBORS; M33 TRIANGULUM GALAXY.
Photo Credit: Robert Gendler; Subaru (NAOJ): CLICK for larger image and see below for links and information.
Located a very close (relatively) 3 million light years distant in the constellation Triangulum is M33; the Triangulum Galaxy. It’s a spiral galaxy that, like Andromeda is a member of the local group of galaxies. In fact, M33 is the second closest non dwarf galaxy to the Milky Way besides Andromeda and in the local group of 44 nearby galaxies it is the third largest of the group besides Andromeda and the Milky Way.
At an apparent magnitude of 5.7 this is one of the furthest naked eye objects visible. Keeping in mind that you will need black skies and perhaps some averted vision to pull it off.
The Triangulum Galaxy was discovered by Italian astronomer Giovanni Battista Hodierna sometime around 1654 and it was independently discovered later by Charles Messier on the night of August 25 and morning of August 26, 1764. Messier added it as number 33 in his catalog of non-comets which he called the “Catalog of Nebulae and Star Clusters” published in 1771.
Its 54 degree inclination relative to Earth gives us a beautiful look at its face. The numerous arms and pockets of brilliant star formation make it a favorite for amateur and professional astronomers alike. M33 is one of the only non-Milky Way galaxies where viewing nebulae and molecular clouds in detail are possible. The center of this galaxy contains an ultraluminous X-ray source which is the most luminous X-ray source in the local group though there doesn’t appear to be a central bulge and or black hole present.
As far as globular clusters go, M33 has been found to contain a modest number of approximately 54 of them but this estimate is almost certainly low. Using data from the Chandra X-ray observatory a the largest stellar mass black hole named “M33 X-7” was discovered in 2007 with 15.7 solar masses and it orbits a companion star that it eclipses every 3.5 days.
M33 also has no issues when it comes to sharing, there have been several streamers of neutral hydrogen and stars detected that connect it to Andromeda and it’s believed that the two may have interacted with each other somewhere in the neighborhood of 5 billion years ago. Like the Milky Way, M33 is seemingly linked gravitationally to Andromeda and is predicted to be on a collision course in approximately 2.5 billion years at that time the two will merge into one. That means that the Andromeda/Milky Way collision predicted to occur in 3.8 to 4.5 billion years will be a whole lot more interesting than we think.
NAME: Messier 33, M33, NGC 598.
WHAT IS IT?: Spiral Galaxy.
HOW FAR AWAY IS IT?: Approximately 3 million light years and after Andromeda is the second closest non-dwarf galaxy to the Milky Way.
HOW BIG IS IT?: At light years in 50,000 diameter it’s the third largest member of our local group of 44 galaxies after Andromeda and the Milky Way and It contains approximately 40 billion stars.
APPARENT MAGNITUDE?: Naked eye magnitude of 5.7. It’s one of the furthest naked eye objects visible.
WHERE IS IT? (General): Constellation Triangulum the “triangle”.
WHERE IS IT? (Exact RA/DEC J2000): RA 01h 33m 50.02s / DEC +30° 39′ 36.7″.
Robert Gendler/Subaru NAOJ page for this object: http://www.robgendlerastropics.com/M33-Subaru-Gendler.html
Another Robert Gendler photo of M33: http://www.robgendlerastropics.com/M33colorNM.html
SEDS Messier 33 page: http://messier.seds.org/m/m033.html
Sky & Telescope page for M33: http://www.skyandtelescope.com/community/skyblog/stargazing/69562222.html
Subaru Telescope/National Astronomical Observatory of Japan (NAOJ): http://www.naoj.org/