Nebula means "Cloud" in Latin.
A nebula is an interstellar cloud of hydrogen, helium, plasma and dust. They are often called "stellar nurseries" because stars are "born" within them.
There are many types of Nebula, some stars have nebula's around them when they approach the final stages of their lives as in Wolf Rayet stars.
Diffuse nebula which are nebula which have no defining shape or boundary.
Dark nebula are so dense that it obscures the light from the background
(Such as the Horsehead Nebula),
or that it blocks out background stars
(Such as the Coalsack Nebula).
Reflection nebula are clouds of dust which are simply reflecting the light of a nearby star or stars. Such as the Witch Head Nebula.
Emission nebula is a cloud of ionized gas (plasma) emitting light of various colors. Such as the Eagle nebula.
Planetary nebula which forms from the shells of stars when they transform into white dwarfs. Such as the Cats Eye Nebula
Protoplanetary nebula which is formed from the rapid creation of a star via stellar evolution. Such as the Egg Nebula
Supernova remnants, the remains of a massive star when it explodes in a supernova explosion The resulting expanding shell of gas creates a diffuse nebula. Such as the Crab Nebula.
Emission nebula glow and reflection nebula reflect the light form other stars
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An absorption nebula is a dark nebula, which absorbs all incident radiation without reemission.
Another popular nebula is the Eagle Nebula, also known as Messier 16. It is located in the constellation Serpens and is famous for the "Pillars of Creation," which are towering columns of interstellar gas and dust where new stars are forming.
The Andromeda Nebula was created in 1967.
nebula
The Stingray Nebula (Hen 3-1357) is a planetary nebula. (The youngest known).
"The Crab" is a nebula.
a type of nebula
A cloud in outer space consisting of gas or dust and planetry nebula is one of the types also called ring nebula or A planetary nebula is an emission nebula consisting of a glowing shell of gas
Emission nebula glow and reflection nebula reflect the light form other stars
The Helix Nebula is a planetary nebula located in the constellation Aquarius, while the Ring Nebula is a planetary nebula located in the constellation Lyra. The Helix Nebula appears more like a disk or helix shape, while the Ring Nebula appears as a ring or donut shape due to its orientation.
The crab nebula.
protostar or nebula
The eye of god is a Helix nebula. Close to a Planetary nebula.
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It is called a Nebula (nebulae for plural). no sorry but your wrong it is a coma It can be both it just depends. The question needs to be more specific