<p><a href="https://en.wikipedia.org/wiki/Nebula" rel="nofollow noreferrer">Nebulas</a> are not static objects - they evolve.</p>

<p>Initially a nebula might contain mostly (as an example) hydrogen, helium and some other elements in a cloud, but over time that material will clump together to form larger and/or denser material.  Eventually parts of some nebula can even condense enough to form a star and it's planets.  Our solar system was (probably) once part of a nebula.</p>

<p>So there's no single answer to your question.  They can contain most forms of matter.</p>

CC BY-SA 3.0
2017-04-04T22:13:26.910Z
Okay, but is it considered plasma when it is ionized?
StellarExile
CC BY-SA 3.0
2017-04-04T22:20:03.443Z
I notice you have supplied your own definition for plasma, so if you think it matches that definition then it's plasma from your point of view.
StephenG - Help Ukraine
CC BY-SA 3.0
2017-04-04T22:20:55.523Z
No, that is the dictionary's definition.
StellarExile
CC BY-SA 3.0
2017-04-04T22:27:42.157Z
@Calvinface It may be a dictionary definition, but it is not the physics definition.
ProfRob
CC BY-SA 3.0
2017-04-04T22:28:49.840Z
Then what is physics's definition? Isn't there multiple definitions of "plasma"?
StellarExile
CC BY-SA 3.0
2017-04-05T06:37:07.263Z
@Calvinface: As Rob writes in his answer, in astronomy we usually use the term "gas" even when it's ionized. Because… astronomers…
pela
CC BY-SA 3.0
2017-04-05T06:57:22.557Z
@Calvinface I'll add that while it's often referred to as gas, the temperature in a nebula is usually well below the freezing point, so I think it's also accurate to think of it as ice.  CO2, CH4, H2O is all ice unless it's close to a heat source.  But being so disburse, it's usually referred to as a gas anyway.   It's a term of convenience.
userLTK
CC BY-SA 3.0
2017-04-04T19:15:37.963Z
2017-04-04T19:15:37.963Z
StephenG - Help Ukraine
<p>After doing research it said that nebulas are made of gas and dust. Are they actually gases and solids, or are they plasma?</p>

CC BY-SA 3.0
2017-04-04T22:14:12.860Z
What definition of a plasma are you using? Astrophysicists rarely bother to formally define gases as plasmas, even if they satisfy thevarious criteria (only one of which is ionisation).
ProfRob
CC BY-SA 3.0
2017-04-04T22:14:46.697Z
an ionized gas consisting of positive ions and free electrons in proportions resulting in more or less no overall electric charge, typically at low pressures (as in the upper atmosphere and in fluorescent lamps) or at very high temperatures (as in stars and nuclear fusion reactors).
StellarExile
CC BY-SA 3.0
2017-04-04T22:32:25.950Z
https://en.m.wikipedia.org/wiki/Plasma_(physics)
ProfRob
CC BY-SA 3.0
2017-04-05T06:35:23.843Z
[Related](http://astronomy.stackexchange.com/questions/15086/how-cold-is-interstellar-space/15087#15087).
pela
<nebula>
What state of matter are nebulae in?
StellarExile
# What state of matter are nebulae in?

(Asked by: username_0 on 2017-04-04)

After doing research it said that nebulas are made of gas and dust. Are they actually gases and solids, or are they plasma?

**Tags:** nebula
> **Comments:**
> **username_1**: What definition of a plasma are you using? Astrophysicists rarely bother to formally define gases as plasmas, even if they satisfy thevarious criteria (only one of which is ionisation).  
> **username_0**: an ionized gas consisting of positive ions and free electrons in proportions resulting in more or less no overall electric charge, typically at low pressures (as in the upper atmosphere and in fluorescent lamps) or at very high temperatures (as in stars and nuclear fusion reactors).  
> **username_1**: https://en.m.wikipedia.org/wiki/Plasma_(physics)  
> **username_2**: [Related](http://astronomy.stackexchange.com/questions/15086/how-cold-is-interstellar-space/15087#15087).  

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## 1 answers

### Answer by username_3 on 2017-04-04. Score: 2 | Accepted answer

[Nebulas](https://en.wikipedia.org/wiki/Nebula) are not static objects - they evolve.

Initially a nebula might contain mostly (as an example) hydrogen, helium and some other elements in a cloud, but over time that material will clump together to form larger and/or denser material. Eventually parts of some nebula can even condense enough to form a star and it's planets. Our solar system was (probably) once part of a nebula.

So there's no single answer to your question. They can contain most forms of matter.

> **Comments:**
> **username_0**: Okay, but is it considered plasma when it is ionized?  
> **username_3**: I notice you have supplied your own definition for plasma, so if you think it matches that definition then it's plasma from your point of view.  
> **username_0**: No, that is the dictionary's definition.  
> **username_1**: @Calvinface It may be a dictionary definition, but it is not the physics definition.  
> **username_0**: Then what is physics's definition? Isn't there multiple definitions of "plasma"?  
> **username_2**: @Calvinface: As Rob writes in his answer, in astronomy we usually use the term "gas" even when it's ionized. Because… astronomers…  
> **username_4**: @Calvinface I'll add that while it's often referred to as gas, the temperature in a nebula is usually well below the freezing point, so I think it's also accurate to think of it as ice.  CO2, CH4, H2O is all ice unless it's close to a heat source.  But being so disburse, it's usually referred to as a gas anyway.   It's a term of convenience.  

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