SOLAR SYSTEM

Detailed explanation-1: -A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity. The Universe consists of billions of galaxies. For example, The Milky Way Galaxy is just one galaxy in the Universe. The Universe is everything.

Detailed explanation-2: -The physical universe is defined as all of space and time (collectively referred to as spacetime) and their contents. Such contents comprise all of energy in its various forms, including electromagnetic radiation and matter, and therefore planets, moons, stars, galaxies, and the contents of intergalactic space.

Detailed explanation-3: -The Short Answer: A nebula is a giant cloud of dust and gas in space. Some nebulae (more than one nebula) come from the gas and dust thrown out by the explosion of a dying star, such as a supernova. Other nebulae are regions where new stars are beginning to form.

Detailed explanation-4: -The universe encompasses all of space, time, matter, and energy. The universe contains everything that exists, from particles of matter smaller than an atom to the largest stars. The universe also includes all forms of energy, from the light you see streaming from stars to invisible radio waves and X-Rays.

Detailed explanation-5: -Galaxies are vast cosmic islands of stars, gas, dust, and dark matter held together by gravity.

Detailed explanation-6: -Galaxies come in different shapes and sizes and can contain billions of stars. Most occur in groups that are also held together by gravity. We now know that the Universe has billions of galaxies, and the Milky Way is only one of them.