Horsehead Nebula and M81, M82 –

Dr. Gerold Holtkamp,, 2023.03.11

The Horsehead Nebula (B33) in Orion

14.2.2023

About one year ago I had photographed the Horsehead Nebula in Orion, but only in B/W, because I didn't have any filters for the mono camera I used (see also report). A year ago a week-long bad weather period had found its end, at least for some nights. This year it was similar; after what felt like months of overcast skies, there were finally a few clear nights - without moon! Finally, I was able to use the LRGB filters that were by now my own. The special challenge was that the object was above the bright city center of Osnabrück.

The Horsehead Nebula in Orion is a dark cloud in front of the luminous emission nebula IC 434. It is about 1500 light years away.

Setup:
Teleskop: Skywatcher APO 80/600
Camera: QHY268M, Gain 60, Offset 20, Chiptemperature -15°C
Filter: LRGB (Antlia) plus CLS-Filter (IDAS-LPS-D2)
Shots: L 90 x 60 s, je RGB 30 x 60 s, je 10 Flats, Darks, Flatdarks
Conditions: no moon, no wind, air temperature about 0°

The galaxies M81/M82 in the Great Bear

28.2.2023

Two weeks later there was another chance. However the conditions were not so rosy: The moon was with 70% already very bright and thus disturbing. So an object as far away as possible from this "sky lantern" offered itself.

The galaxy M81 has about the shape of our own galaxy and is about 12 million light years away from us. M82 we see from the side. But it has probably the structure of a so called bar galaxy. It is about 14 million light years away from us. So both galaxies are not only neighbors in our sky. Together with other galaxies they form the M81 galaxy group.

Setup: Telescope: Skywatcher APO 80/600 Camera: QHY268M, Gain 60, Offset 20, Chip temperature -15°C Filter: LRGB (Antlia) plus CLS filter (IDAS-LPS-D2) L 60x60 s, each RGB 20x60 s, each 5 flats, darks, flatdarks. Conditions: Half moon, about 70° away, no wind, air temperature about -2°