Bode’s Nebula is actually a galaxy?

Yep. Galaxy M81 was discovered in 1774 by Johann Elert Bode along with M82 pictured here, but at that time astronomers didn’t know about galaxies. The word “nebula” means “a cloud, fog, or mist” in Latin. So astronomical objects in the night sky that appeared cloudy or misty in appearance were labeled as nebulae. It wasn’t until 1924 that Edwin Hubble declared that some of these nebulae were quite different from the others. He figured out that many of these objects were actually galaxies, like our own galaxy the Milky Way, and that they contained billions of their own stars and nebulae.

So yeah, Bode’s Nebula, aka Messier 81, is actually a galaxy. In this picture, M81 is the grand spiral galaxy in the upper left, and its close neighbor, Messier 82, is the lower right galaxy. These two galaxies are very close together (astronomically speaking of course) at about 150,000 light years away from each other from core to core. See all that dust that surrounds these two galaxies? That stuff is called Integrated Flux Nebula or IFN, and it’s actually in our galaxy. And those stars in the picture are also in our own galaxy too. So M81 and M82 are being photobombed by our own nebulae and stars, but in a beautiful/misty kind of way.

Picture: I imaged these galaxies back in March using a Schmidt Cassegrain telescope on an equatorial tracking mount with a ZWO ASI533mc RGB astronomy camera. I tried processing it shortly after capturing the data, but got frustrated with some data issues. Although imaging with RGB cameras (aka “one shot color” cameras) can be easier initially, they can create problems in processing that you typically won’t have when using a monochrome camera with filters. So it took me a while to get back to finishing this photo.

Pixinsight Workflow:

Dynamic Crop

Dynamic Background Extraction

Deconvolution

Denoise with TGVdenoise and Multiscale Median Transform

Background Neutralization

Color Calibration

Repaired HSV Separation

RGB Working Space

Luminance Extraction

Arc Sinh Stretch of RGB

Masked Stretch of LUM

HDR Multiscale Transform on LUM

LRGB Combination

Over to Photoshop for final color and levels balancing

ACQUISITION DETAILS: March 7, 2021 | 200x60s | Gain 100 | Temp -10c | 30x Darks, Flats, Flat Darks | Total Integration Time 3.33 hrs

EQUIPMENT: Celestron 9.25” SCT | Starizona Hyperstar Adapter | ZWO ASI533mc | ZWO 30mm F4 Guidescope | ZWO ASI224mc Guide Camera | Skywatcher EQ6-R Pro | ZWO ASIair | ZWO UV/IR Cut Filter

PROCESSING: Pixinsight | Photoshop | Starnet ++ | Macbook Air M1 2020