SOLAR SYSTEM

Detailed explanation-1: -A galaxy is a giant, spinning object made of gas, dust, and stars held together by gravity. Galaxies come in different shapes and sizes and can contain billions of stars. Most occur in groups that are also held together by gravity.

Detailed explanation-2: -Galaxies are made up of a collection of stars and are formed by the condensation of the gas of the intergalactic medium composed of mostly hydrogen and a bit of helium.

Detailed explanation-3: -Type c spiral galaxies have the most gas and dust.

Detailed explanation-4: -Many of those points of light are actually galaxies-collections of millions to trillions of stars. Galaxies are composed of stars, dust and dark matter, all held together by gravity. Astronomers aren’t certain exactly how galaxies formed. After the Big Bang, space was made up almost entirely of hydrogen and helium.

Detailed explanation-5: -Galaxies form out of immense clouds of gas that collapse and rotate. As they evolve, stars form within them. Entire galaxies can collide, changing their appearance. Looking deep into space, we see galaxies at earlier stages in their lives, and learn more about their evolution.