M46

[petevasey]

This has always been on my hit list, but never imaged.  Until last night which was unexpectedly clear for a few hours after many cloudy nights.  M46 is very low in the South for me, never getting higher than 20 degrees, so generally hazy and disturbed, leading to a certain amount of star bloating, although the Starlight Xpress AO unit did it's best - the guide star was bright enough for 5 frames per second.  Last night conditions were not good and I had to scrap some subs due to thin cloud, but managed to get usable 9 Luminance and 6 each RGB.  All 5 minutes binned 2x2, QSI 683 on RC10.  The cluster pretty well fills the field of view, but I wanted also to capture the planetary nebula NGC2438 in the foreground.  All things considered I'm reasonably pleased with the result.

Forecast to be clear tonight, but being New Year's Eve I'm out visiting all evening. Typical!   Maybe I'll get something after midnight 😉

Cheers, and Happy New Year to all.

Peter

Edited December 31, 2019 by petevasey

[petevasey]

There is another Nebula in M46, the Calabash Nebula (OH 231.84 +4.22). This is a protoplanetary nebula - a planetary in early stage of formation. It is believed to be part of M46, not superimposed.

Barely visible in my image, this is a highly stretched monochrome crop, but just identifiable when compared with Adam Block's image, which of course was taken with a 32" telescope at 9000 ft above sea level! I may return to M46 and try for some Hydrogen-alpha data to bring up the fainter parts of NGC2438 and perhaps the Calabash, but because of the low altitude it will need data from more than one night. And the way the weather has been, it doesn't look very promising.

The Hubble image is absolutely gorgeous.

Edited January 7, 2020 by petevasey