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

StellarExile
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    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 Apr 04 '17 at 22:14
  • 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 Apr 04 '17 at 22:14
  • https://en.m.wikipedia.org/wiki/Plasma_(physics) – ProfRob Apr 04 '17 at 22:32
  • Related. – pela Apr 05 '17 at 06:35

1 Answers1

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Nebulas 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.

StephenG - Help Ukraine
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  • Okay, but is it considered plasma when it is ionized? – StellarExile Apr 04 '17 at 22:13
  • 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 Apr 04 '17 at 22:20
  • No, that is the dictionary's definition. – StellarExile Apr 04 '17 at 22:20
  • @Calvinface It may be a dictionary definition, but it is not the physics definition. – ProfRob Apr 04 '17 at 22:27
  • Then what is physics's definition? Isn't there multiple definitions of "plasma"? – StellarExile Apr 04 '17 at 22:28
  • @Calvinface: As Rob writes in his answer, in astronomy we usually use the term "gas" even when it's ionized. Because… astronomers… – pela Apr 05 '17 at 06:37
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    @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 Apr 05 '17 at 06:57