Key Difference: Nebula is a cloud in deep space consisting of gas or dirt/dust (e.g. cloud formed after a star explodes). Whereas, a star is a luminous celestial body that has a spherical shape. It is made up of plasma, hydrogen, helium, etc.

Nebula and star are two different types of astronomical object existing in the universe. Nebula is a cloud in deep space consisting of gas or dirt/dust. Example: A cloud formed after a star explodes. The word Nebula has been derived from the Latin word, meaning “cloud”. The plural term of nebula is nebulae. In the earlier time, galaxies were also called as nebula by astronomers because of their fuzzy appearance. However, nowadays the word nebula is referred for extended objects consisting mostly of gas and dust. The “Pillars of Creation” is the most famous images of NASA’s. Nebula comes in many shapes and sizes and form in many different ways.

A star, on the other hand, is a massive, luminous sphere of plasma that is held together by its gravitational pull. The planets revolve around the star. The obvious example of this is Earth, which is a planet, revolves around the closest star in its vicinity, i.e. the Sun. Most stars in the universe are much larger than the Sun. Some are even up to 1,000 times as large. The star is also the source of most of the energy on the planets. The planets are able to reflect the light cast by the star. From Earth, one can see many distant stars of the universe. These stars appear as a mass of fixed luminous points in the sky due to their immense distance. Humans have often named prominent stars and have grouped them together into constellations.

Comparison between Nebula and Star:

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