Title: “7 Fascinating Facts about the Universe”

Fact 1: The Universe is estimated to be around 13.8 billion years old. This age is determined by studying the oldest known light in the cosmos, known as the Cosmic Microwave Background Radiation.

Fact 2: The observable Universe is vast, spanning a distance of approximately 93 billion light-years in diameter. However, it is important to note that the Universe may extend beyond what we can currently observe.

Fact 3: Dark matter, a mysterious substance that does not interact with light or other electromagnetic radiation, makes up about 27% of the Universe’s total mass-energy. Its presence is inferred through its gravitational effects on visible matter.

Fact 4: The Universe is expanding at an accelerating rate. This discovery, made in the late 1990s, led to the concept of dark energy, a hypothetical form of energy that is thought to be responsible for this accelerated expansion.

Fact 5: The largest known structures in the Universe are galaxy clusters, which can contain thousands of galaxies held together by gravity. The most massive galaxy cluster discovered so far is the El Gordo cluster, located about 7 billion light-years away.

Fact 6: Black holes are regions in space where gravity is so strong that nothing, not even light, can escape their gravitational pull. They are formed from the remnants of massive stars that have undergone gravitational collapse.

Fact 7: The Universe is filled with countless galaxies, each containing billions or even trillions of stars. The estimated number of galaxies in the observable Universe is around 2 trillion, but this number could be much higher due to the vastness of the cosmos.

These seven facts provide a glimpse into the awe-inspiring nature of our Universe, showcasing its age, size, composition, and the intriguing phenomena that exist within it.