Nebula are an accumulation of gas particles.
Bearing in mind that there untold billions of atoms in the cosmos.
Any two atoms have a gravitational attraction between them. they come together, thus attracting more gas particles by gravitational attraction.
These gas particles become so crowded that they begin to glow, (the nebula).
The analogy, is a dance hall/disco; maybe two people will statr to dance. Eventually a lot more people arrive on the dance floor, and it becomes hot and crowded.
Under further gravitational attraction these hot crowded gas particles keep accumulating into a hot glowing ball. Because partiucles are now so crowded nuclear fusion starts, and releases energy. Hence a Star/Sun.
Because this process takes billions of years we do not instantaneously see it going on.
NB All stars are nuclear reactors in space.
lenpollock
If the pressure inside a nebula exceeds the force of gravity, it would expand and push against the force of gravity, causing the nebula to push outward and disperse. This could disrupt the process of star formation and prevent gravity from collapsing the nebula into a protostar.
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.
Shred Nebula happened in 2008.
Hades Nebula happened in 1987.
If the pressure inside a nebula exceeds the force of gravity, it would expand and push against the force of gravity, causing the nebula to push outward and disperse. This could disrupt the process of star formation and prevent gravity from collapsing the nebula into a protostar.
If you are not wearing a suit you could die
A supernova occurs.
The Crab Nebula is a nebula.
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.
A nebula is a vast cloud of gas and dust in space. A solar nebula specifically refers to the cloud of gas and dust from which our solar system formed around 4.6 billion years ago.
nebula
The Stingray Nebula (Hen 3-1357) is a planetary nebula. (The youngest known).
a type of nebula
"The Crab" is a nebula.