Question

what are nebulae?
where is it found ?
what is dark matter

Answer 1

a bright area in the night sky that is caused by a mass of dust or gas or by a large cloud of stars that are far away

Answer 2

Nebulae exist in the space between the stars—also known as interstellar space. The closest known nebula to Earth is called the Helix Nebula. It is the remnant of a dying star—possibly one like the Sun.

Dark matter, a component of the universe whose presence is discerned from its gravitational attraction rather than its luminosity. Dark matter makes up 30.1 percent of the matter-energy composition of the universe; the rest is dark energy (69.4 percent) and “ordinary” visible matter (0.5 percent).