Space Facts for Kids
Out-of-this-world facts about the universe
Despite what movies show, the asteroid belt between Mars and Jupiter is mostly empty space. If you added up all the asteroids in the belt, they'd form a ball less than half the size of Earth's Moon. Spacecraft travel through it without hitting anything.
Comets actually have two tails, not one! One tail is made of dust that curves behind the comet as it moves, and the other is made of ionized gas that always points directly away from the Sun due to solar wind, no matter which direction the comet is going.
Light travels so fast that it can go around the entire Earth about 7 times in one second. But even at that speed, light from the Sun takes about 8 minutes to reach Earth. Light from the nearest star beyond our Sun takes over 4 years to arrive.
A NASA spacesuit costs about $12 million to make! These suits are essentially personal spacecraft — they provide oxygen, maintain air pressure, control temperature, and protect astronauts from the harsh environment of space.
Saturn's small moon Enceladus has geysers near its south pole that shoot jets of water vapor and ice crystals hundreds of miles into space. This water comes from a subsurface ocean, making Enceladus another top candidate for finding life beyond Earth.
Galaxies come in four main shapes: spiral (like our Milky Way), elliptical (oval or round), lenticular (disk-shaped without spiral arms), and irregular (no definite shape). There are an estimated 2 trillion galaxies in the observable universe.
Neil Armstrong's footprints from the first Moon landing in 1969 are still there — perfectly preserved. Because there's no wind or weather on the Moon, nothing disturbs the surface. They could last for millions of years.
When a massive star explodes in a supernova, it can briefly outshine an entire galaxy containing hundreds of billions of stars. The explosion releases more energy in seconds than the Sun will produce in its entire 10-billion-year lifetime.
Earth is surrounded by an invisible magnetic field called the magnetosphere that shields us from harmful solar radiation and cosmic rays. Without this magnetic field, solar wind would gradually strip away Earth's atmosphere, as happened on Mars.
Uranus is tilted so far on its side — about 98 degrees — that it essentially rolls around the Sun like a ball. This means each pole gets 42 years of continuous sunlight followed by 42 years of complete darkness.