Tag: M43

M42 Great nebula in Orion

I don’t want to repeat myself, therefore the description of the most famous nebula visible from the northern hemisphere can be found here.

The previous picture has some strange halo around the bright star Hatsya and I was thinking why. Recently, a similar picture came out of my telescope and I realized that this strange halo is caused by the frost on the secondary mirror. I manufactured a homemade dew shield and I don’t have these problems anymore.

This picture is, as usual, composed of narrowband pictures. When I look at it I am still not happy, therefore I hope next year will be better weather and I will make a better picture.

Telescope:Newton 254/1000 mm
Aperture:254 mm
Focal length:730 mm
Mount:Gemini GF53f
Autoguiding:Orion Mini, TS 50/160 mm
Camera:Moravian instruments G2 8300M @-30C
Corrector:ASA 0.73 reducer
Filters:Baader Ha, OIII
Exposure:17xHa, 15xOIII, 240 s, 10xHa, OIII 60 s bin 1x1

M42 Great nebula in Orion

I think everyone knows constellation Orion, but only few people know that there is Great nebula in Orion, visible even by naked eye. It’s located between his belt and legs. The nebula is approximately 1300 light years from earth and it has 24 light years in diameter. Red color shows a lot of hydrogen gas, which is essence for star formation. In fact, the Orion nebula is the closes location from Earth, where the stars are born.

Since this nebula is visible by naked eye, with help of telescope even with sub-urban area, it’s not necessary to use long exposure times. I used just 3 minutes exposures and the picture yielded in nearly overexposed photo. Small nebula on the right side is NGC1973 Running man nebula.