**Unveiling the Mysteries of the Cosmos: Lesser-Known Facts About Space**

Space, the final frontier, has captivated human imagination for centuries. While we’ve made tremendous strides in our understanding of the universe, there remain countless intriguing and lesser-known facts about space that continue to surprise and fascinate. Here are some cool facts about space that many people might not know.

### The Universe is Almost Perfectly Flat

One of the most astonishing discoveries in cosmology is the shape of the universe. Observations from the Cosmic Microwave Background (CMB) radiation suggest that the universe is flat with only a 0.4% margin of error. This means that, on a large scale, the universe conforms to Euclidean geometry, where parallel lines never meet and the angles of a triangle sum to 180 degrees.

### There are More Stars in the Universe Than Grains of Sand on Earth

The sheer number of stars in the universe is mind-boggling. Estimates suggest that there are around 100 billion galaxies in the observable universe, each containing anywhere from 100 million to over a trillion stars. This means the total number of stars exceeds the number of grains of sand on all the Earth’s beaches combined.

### The Coldest Place in the Universe

Space is cold, but the Boomerang Nebula holds the record for being the coldest place in the universe, with a temperature of just 1 Kelvin (−272.15°C). This temperature is only one degree above absolute zero, where atomic motion virtually ceases. The nebula is cooling due to the rapid expansion of gas expelled by a dying star.

### A Planet Made of Diamond

55 Cancri e, also known as the “diamond planet,” is an exoplanet that orbits a star in the constellation of Cancer. This planet is believed to have a carbon-rich composition, and with its extreme pressure and heat, it’s theorized that a large part of the planet could be composed of diamond. This makes it one of the most extraordinary and valuable planets discovered.

### The Largest Volcano in the Solar System

Olympus Mons on Mars is the largest volcano in the solar system, standing about 22 kilometers (13.6 miles) high, nearly three times the height of Mount Everest. Its base is approximately 600 kilometers (373 miles) in diameter, about the size of the state of Arizona. Olympus Mons is a shield volcano, similar to those in Hawaii, but far larger.

### Rogue Planets Drifting Through Space

Not all planets are tied to a star. Rogue planets are planetary-mass objects that drift through the galaxy without orbiting any star. These planets are believed to form in a star system and are later ejected due to gravitational interactions. Estimates suggest that there could be billions of rogue planets in our Milky Way galaxy alone.

### Dark Matter and Dark Energy Dominate the Universe

What we see in the universe — stars, planets, galaxies — accounts for less than 5% of the total mass and energy. About 27% is dark matter, which interacts with regular matter through gravity but not light, making it invisible and detectable only through its gravitational effects. The remaining 68% is dark energy, a mysterious force driving the accelerated expansion of the universe. Despite its prevalence, we know very little about the nature of dark matter and dark energy.

### The Great Attractor

Our Milky Way galaxy, along with hundreds of thousands of other galaxies, is moving toward a gravitational anomaly known as the Great Attractor. Located about 150–250 million light-years away in the direction of the Centaurus and Hydra constellations, the Great Attractor exerts a tremendous gravitational pull, affecting the motion of galaxies over a large region of the universe.

### The Farthest Human-Made Object

Voyager 1, launched by NASA in 1977, is the farthest human-made object from Earth. As of now, it has traveled over 14 billion miles from our planet. Voyager 1 is in interstellar space, the region between stars, and continues to send back data to Earth, providing valuable information about the outer reaches of our solar system and beyond.

### Time Dilation in Space

Einstein’s theory of relativity predicts time dilation, where time moves slower in stronger gravitational fields or at higher velocities. For example, astronauts aboard the International Space Station (ISS) age slightly slower than people on Earth due to the ISS’s high orbital speed and the weaker gravitational field in orbit. After a year in space, an astronaut would be a few milliseconds younger than if they had spent that time on Earth.

### The Loneliest Galaxy

A galaxy known as MCG+01–02–015, located about 300 million light-years away, is often referred to as the “loneliest” galaxy. It exists in a vast cosmic void, a region of space that is unusually empty, with few galaxies or stars. This isolation makes it one of the most solitary galaxies in the known universe.

### Hypervelocity Stars

While stars typically move through the galaxy at velocities of a few hundred kilometers per