Space Facts for Kids
Out-of-this-world facts about the universe
Gold on Earth was made when two neutron stars collided billions of years ago in an event called a kilonova. These cataclysmic mergers are one of the main ways heavy elements like gold, platinum, and uranium are created and spread through the universe.
Billions of years ago, Mars likely had liquid oceans covering a third of its surface, rivers, and possibly even an Earth-like atmosphere. Scientists have found ancient riverbeds, deltas, and shorelines preserved on Mars's surface — evidence of its watery past.
On the ISS, astronauts sleep in small sleeping compartments and must strap themselves in so they don't float around in their sleep. Without strapping in, a sleeping astronaut could bump into equipment or accidentally block a ventilation opening.
A star's color tells you how hot it is. Red stars are the coolest, at around 3,000°C (5,400°F). Yellow stars like our Sun are medium temperature. Blue-white stars are the hottest, burning at over 30,000°C (54,000°F). So in the universe, blue is hot and red is cool!
China has its own permanently crewed space station called Tiangong, meaning 'Heavenly Palace.' It became fully operational in 2022 and is capable of hosting three astronauts (called taikonauts). China became only the third country to independently send humans to orbit.
Planets form when small rocks called planetesimals collide and clump together under gravity over millions of years. This process, called accretion, starts with dust grains sticking together, growing into pebbles, boulders, and eventually planets.
On Venus, the Sun rises in the west and sets in the east — the opposite of Earth. This is because Venus rotates in the opposite direction to most planets. If you stood on Venus (and somehow survived!), you'd see the Sun rise in the west every 117 Earth days.
Every individual star you can see in the night sky with your naked eye is part of our own Milky Way galaxy. The farthest star visible to the naked eye is about 16,000 light-years away. Other galaxies appear as fuzzy smudges of light containing billions of stars.
Helium was discovered on the Sun before it was ever found on Earth! In 1868, scientists studying the Sun's light spectrum spotted a yellow line that didn't match any known element. They named it helium after Helios, the Greek god of the Sun. Helium was finally found on Earth 27 years later.