A Nebula is a massive cloud of dust, gas and debris (sometimes left over from a star that has died in a supernova explosion) drifting in interstellar space.
It is from these nebula that stars are thought to form. Once the stars "come to life" this is thought to kick start the formation of other stars and planets from the remaining gas, dust, rock, metal in the dust cloud.
A nebula is a physical change. It is a cloud of gas and dust in space that is not undergoing any chemical reactions. The process of a nebula forming into a star involves physical changes such as gravity causing the gas to condense and heat up.
You would least expect to find an ionization nebula in a region that lacks hot, massive stars. These stars are responsible for emitting the high-energy ultraviolet radiation needed to ionize the gas in the nebula and make it visible. Therefore, areas with mainly low-mass and old stars would be less likely to host an ionization nebula.
An incandescent body of gas is called a nebula. Nebulas are large clouds of dust and gas in outer space that emit light due to the energy generated by the stars or other processes happening within them.
It is very inert. However, under extreme conditions it can be made to react - to form compounds. Argon hydride was detected in the Crab Nebula in 2010.
The key to this is that NO star uses up ALL of its hydrogen. In fact, they only use up the Hydrogen in their cores, where pressure and temperature are highest. In the case of a red giant, the star is at the stage of burning Helium into Beryllium, Boron and Carbon, which requires much more heat (the heat is "borrowed" from the previous collapsing of the star at the end of the main sequence phase) and continues with a much denser core. When a star expands into a red giant, it blows some of its Hydrogen mass into space. Later, when it simply cannot sustain any fusion reactions in its core, it still contains a considerable amount of hydrogen in the outermost layers, and the subsequent collapse causes a rebound (supernova) that blows about 50% of the original star's mass - most of the hydrogen plus some of the heavier elements into space. When that blown away material collides with a large gas cloud in space which is mostly hydrogen, and compresses that cloud enough that the material can then collapse and form another new star.
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