M108 - The Surfboard Galaxy

Messier 108 (NGC 3556), nicknamed the "Surfboard Galaxy," is a barred spiral galaxy (type SB(s)cd) in the constellation Ursa Major, lying approximately 46 million light-years away. Discovered by Pierre Méchain in 1781 and later added to Messier’s catalogue, M108 is seen nearly edge-on, giving it its elongated "surfboard" profile. The galaxy spans about 110,000 light-years and contains numerous HII regions, dust lanes, and signs of active star formation scattered along its disk. It is also part of the M109 galaxy group.

This image was captured with just 1 hour 20 minutes of LRGB integration using a 70 cm telescope in Spain via Telescope Live. With only two frames per LRGB channels, stacking presented major challenges - particularly "color blips" that rejection algorithms couldn't fully eliminate. Stacking and synthetic luminance generation were done in Astro Pixel Processor.

A careful workflow in PixInsight addressed the artifacts (all while the data remained in a linear state):

1. SXT was used to extract stars, bringing the blips along with them.

2. PixelMath created a custom "blip mask."

3. MMT (6 layers) substituted the affected regions using only the residual layer.

4. Stars were then reintroduced, and any remaining color blips were manually removed with the Clone Stamp tool.

Despite the short exposure and data limitations, the final image reveals M108's slender disk, dusty midplane, and scattered star-forming regions - a respectable result from a challenging dataset.

Sources:

wikipedia.org

messier-objects.com

science.nasa.gov

theskylive.com

Data credit: Telescope.Live