From: <maupperl@gmail.com>

Date: December 9, 2013 2:03:07 PM MST

To: <Astro_IIDC@yahoogroups.com>

Subject: XMas Themed Print Notes

Hi Folks;

Here are some brief notes for the 11x14" image X-Mas image.

I usually print this off on a sticky ink jet page and then attach it to the back of the print. That way people have some idea what they are looking at.

Background: Core area of Messier 42 (The Orion Nebula) centered on Trapezium and the inset images (Left to Right) are:

Top Row:  NGC 6992 (Veil Nebula East - Witches' Broom North) , Messier 1 (Crab Nebula), NGC 7635 (Bubble Nebula)

Middle Row: Messier 27 (DumbBell Nebula) , NGC 2438 (a ring Nebula in Messier 46) NGC 2392 (Eskimo Nebula) , Messier 57 (Ring Nebula)

Bottom Row: NGC 1973 (Running Man Nebula), IC 434 (Horse Head Nebula) , NGC 6995 (Veil Nebula East - Witches' Broom South)

Different Nebula types in this image:

EMISSION NEBULA = (Messier 42 Orion Nebula, NGC 7635 Bubble Nebula)

An emission nebula is a cloud of high temperature gas in which the atoms are energized with ultraviolet light by a nearby star and emit radiation until they fall back down to lower energy states. These nebulae work much in the same way as a neon light. Emission nebulae are normally a space of consistent and ongoing star creation. The red is produced by hydrogen (H-alpha), while the blue and green primarily arise from oxygen (OII and OIII, respectively).

REFLECTION NEBULA = (NGC 1973 Running Man Nebula)

A reflection nebula are normally just clouds of dust and gas that reflect nearby starlight instead of making thier own, these nebula are often blue because blue is more efficient for scattering light, reflection nebulae also produce many stars and are commonly found close to or melded with emission nebulae.

DARK NEBULA  = (IC 434 Horse Head Nebula)

A dark nebula are physically very very similar to a reflection nebula and the only reason they appear any different is because the orientation of the light source, the nebula, and earth. essentially all that a dark nebula is doing is blocking out the light of everything behind it, dark nebula will also produce stars.

PLANETARY NEBULA  = (Messier 1 Crab Nebula,  Messier 27 DumbBell Nebula, NGC 2438 a ring Nebula in Messier 46, Messier 57 Ring Nebula, NGC 2392 Eskimo Nebula,, 

A planetary nebulae, have nothing to do with planets, instead, they are the gas remnants thrown out by some stars near the end of their lifespan, our own sun will probably produce a planetary nebula in about 5 000 000 000 years from now planetary nebulae do NOT produce stars.

SUPERNOVA REMNANTS =  (NGC 6992 Veil Nebula East - Witches' Broom North, NGC 6995 Veil Nebula East - Witches' Broom South)

A supernova is formed when a large star explodes at the end of its lifespan, but a supernova remnants, although not specifically a nebula, is the part of the star that is not turned into a supernova but is instead blown off into space. The red is produced by hydrogen (H-alpha), while the green primarily arise from oxygen (OIII).