Space is such an enigma. There so many aspects of the universe that remain unexplored and offer unlimited potential. As such, it is a source of endless fascination for droves of spectators who are drawn to the complexities that are hidden within the cosmos and throughout its vastness. With that in mind, here are five stunning facts about space to contemplate.

The Sun’s Mass Accounts for Virtually All of the Mass Within the Solar System–No, that is not an exaggeration. The mass of the Sun, which is primarily composed of 75 percent hydrogen and more than 20 percent helium, consumes approximately 99.9 percent of the mass of the solar system and possesses a mass that is nearly 350,000 times that of Earth.

The Exact Number of Stars, Planets, and Galaxies Within the Universe Are Unknown–Given the vast and boundless nature of the universe, it is impossible to determine how many stars, planets, galaxies, and other objects are present. Therefore, estimates are the best guidelines available. Currently, the universe is believed to contain more than 100 billion galaxies. Within the Milky Way galaxy alone, which houses the planet Earth, there are believed to be 200-400 billion stars and an estimated 9 billion planets.

A Chunk of the Earth Created the Moon–According to scientific theory, a giant asteroid struck the celestial body in its early days, and the resulting collision broke a piece of Earth off. Thus, this chunk of Earth morphed into the Moon and began orbiting its creator, thanks to its gravitational forces.

Halley’s Comet Will Not Enter Earth’s Orbit Again Until 2061–This well-known phenomenon, which is likely the most famous comet in the universe, was named after English astronomer Edmond Halley and orbits Earth every 75-76 years. Its last appearance was in 1986 and it is predicted to return in 2061.

Outer Space Is Silent–Due to the fact that space has no atmosphere, sound cannot travel. Radio waves, however, can be sent and received. This is why astronauts communicate via radio while in space.

There are so many facets of space that remain undiscovered. The cosmos are filled with mysteries and boundless possibilities. Given the vast and enigmatic nature of the universe, is it any wonder why people are so fascinated by its complexities? These five stunning facts about space are just the tip of the iceberg.