Hydrogen and a small amount of Helium.
A GALAXY Does consist of stars.It's consisted out of gas,dust,and stars.
Stars are scattered all across our universe but guess what? there are no stars in our solar system besides the sun!
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The Universe.
Without gravity the universe would be much less interesting, and would consist only of a very thin cloud of gas, with no stars or planets, or computers or web-sites.
The most common element in the Universe - and in most stars - is hydrogen. Stars have smaller amounts of helium, and still smaller amounts of "metals" (heavier elements). Some stars may have burnt out their hydrogen, and consist mainly of helium and heavier elements. It really depends on the star's stage in its life cycle.
A galaxy contains billions of stars. A universe contains billions of galaxies.
Such stars consist mainly of hydrogen-1.
If there is then we, being right beside a star, cannot know of it. We appear to be surrounded by stars and galaxies.
All stars and galaxies are in the universe.
well, it could be the Doppler Effect, Red or Blue shift. or it could also be the expanding universe, or because of the ripples
The Universe.