A light-year is the distance light travels in one year, approximately 9.461 trillion kilometers.

The Milky Way is a barred spiral galaxy with a diameter of about 100,000 light-years.

The Milky Way is part of the Laniakea Supercluster, which is about 500 million light-years across.

The observable universe is estimated to contain around 100 trillion galaxies.

Elliptical galaxies are the most common type of galaxy in the universe, accounting for about 70% of all galaxies.

The Andromeda Galaxy, also known as Messier 31, is the closest major galaxy to the Milky Way, located about 2.5 million light-years away.

The Hercules-Corona Borealis Great Wall is the largest known structure in the universe, stretching over 10 billion light-years.

The universe is estimated to be about 13.8 billion years old.

The Big Bang Theory is the prevailing cosmological model for the universe from the earliest known periods through its present expansion and cooling.

The Cosmic Microwave Background is the remnant radiation of the Big Bang, providing evidence for the expansion of the universe.

Dark Energy is a hypothetical form of energy believed to be responsible for the observed acceleration of the universe's expansion.

Dark Matter is a hypothetical form of matter that does not interact with electromagnetic radiation and is thought to make up most of the universe's mass.

The Higgs Boson is a subatomic particle that gives mass to other particles.

The Neutrino is a subatomic particle with no electric charge and very little mass.

A Singularity is a hypothetical point in space-time where all matter and energy were concentrated before the Big Bang.