Space Facts for Kids
Out-of-this-world facts about the universe
About 68% of the universe is made of dark energy — a mysterious force that is causing the universe to expand at an ever-increasing speed.
Without gravity, astronauts lose about 1% of their bone density per month in space. They must exercise for around two hours every day to slow this process.
Mars has two small, irregularly shaped moons called Phobos and Deimos. They are both potato-shaped and are thought to be captured asteroids.
Earth's magnetic north pole is not fixed — it moves by about 55 kilometres per year and has flipped completely hundreds of times in Earth's geological history.
The Sun is about 30% brighter now than when Earth formed 4.5 billion years ago, and it will continue to slowly brighten over billions of years.
NASA's New Horizons spacecraft flew past Pluto in 2015, sending back the first close-up images of the dwarf planet after a nine-year, five-billion-kilometre journey.
Every star in the night sky is a massive ball of hot plasma held together by gravity, constantly converting hydrogen into helium through nuclear fusion deep in its core.
The Northern and Southern Lights — called the aurora — are caused by particles from the Sun hitting Earth's magnetic field and exciting gas atoms in the atmosphere to glow.
Mars gets its red colour from iron oxide — rust — on its surface. The sky on Mars is actually a dusty butterscotch-orange colour during the day.
After a star like our Sun dies, it leaves behind a white dwarf — a city-sized remnant that slowly cools over billions of years. The universe is not yet old enough to have produced a cold black dwarf.