Messier 108, also known as the Surfboard Galaxy, is a nearly edge-on barred spiral galaxy with distinctive dust lanes stretching across its face. It is one of the largest and brightest members of the Ursa Major galaxy cluster, showcasing loosely wound spiral arms and regions of active star formation. Despite its edge-on orientation, M108 reveals a wealth of detail to astrophotographers, including a mottled and dusty appearance with young star clusters visible against its intricate background. The galaxy’s lack of a pronounced bulge or core contributes to its unique surfboard-like appearance when viewed through telescopes.
Names and Catalog numbers
- Surfboard Galaxy
- Messier: M108
- NGC: NGC 3556
- UGC: UGC 6225
- PGC: PGC 34030
Position and the cosmic neighborhood
Messier 108 is easily located in the night sky, positioned just 1.5 degrees southeast of the bright star Merak (Beta Ursae Majoris), one of the Pointer Stars in the Big Dipper. This convenient location makes it a popular target for amateur astronomers. M108 shares its cosmic neighborhood with the famous Owl Nebula (M97), which can be found only 48 arcminutes southeast of the galaxy, often allowing both objects to be captured in the same wide-field astrophotography image. As part of the Ursa Major Cluster of galaxies, M108 resides within the larger Virgo Supercluster, offering astrophotographers an opportunity to capture a slice of the cosmic web.
Nice to Know
- M108 contains supershells of gas, driven by bursts of star formation and supernova explosions.
- A type II supernova (1969B) was observed in M108 on January 23, 1969, peaking at magnitude +13.9.
- The galaxy’s central region contains a supermassive black hole estimated to be 24 million times the mass of the Sun.
- M108 can take high magnifications well, making it an excellent target for detailed astrophotography.
Brightness, distance and size
Messier 108 shines with an apparent magnitude of 10.0, making it visible through small telescopes under dark sky conditions. Located approximately 46 million light-years from Earth, the galaxy spans an impressive 130,000 light-years in diameter. In terms of angular size, M108 appears as an elongated streak measuring about 8.7 by 2.2 arcminutes in the night sky, presenting astrophotographers with a challenging yet rewarding target that can reveal intricate dust lanes and star-forming regions when captured with sufficient exposure and resolution.
