M 76

Date: 1.11.2007 - seeing 8/10; transp. 8/10 4.1.2008 seeing 6/10; transp. 7/10;

Scope: 9" TMB Apo f/9

CCD: 1.11: 2 hours SXV M25C; 4.1.2008: 5.5 hours; October, November, December 3h Ha, 2.5h O3 /f/7)

Software: AstroArt4 image acqu. guiding, preprocessing. Also CCD sharp, Registax,

Processing: postprocess. PS CS2 and Pix InSight LE



M76 can be found in the constellation of Perseus quite close to Andromeda. It's central star appears to be a binary system with a yellowish (southern) component. But this is only an optical binary system at a distance of 1.4 arc". Hubble Space Telescope revealed the southern component to be located some thousands of lightyears in the background and therefore the central star is solitude. (you can see this optical binary system in the enlarged crop-image.)
This PN (the faintets of all Messier objects) was long time believed to be a galaxy until precise spectroscopic investigations from the early 19th century revealed its true nature?
the PN is said to be seen from an edge on view - the "barr" or "cork" like brighter part is said to be a kind of ring-like structure - consisting of the material the very hot CS blows out. this brigther part holds approx. 1 arc min in longitud. axis. however the fainter outer parts - the wings of the "butterfly" measure approx. double size.
and further out there are remnants from the periode when the CS dwelled in its "super-giant" phase, commencing to evaporate outer star-mass. it has some diameter of approx. 4-5 arc minutes.