1Last month our class visited the planetarium in the city.
2The guide began with the Sun at the centre of everything.
3The Sun is a star made mostly of hydrogen and helium.
4Its gravity holds eight planets in their orbits.
5Mercury is the closest planet and has almost no air.
6Venus is hotter than Mercury because of its thick atmosphere.
7Earth is the only planet known to support living things.
8Mars looks red because its soil contains rusty iron.
9Jupiter is so large that all other planets could fit inside it.
10Its Great Red Spot is a storm bigger than our whole planet.
11Saturn is famous for rings made of ice and rock.
12Uranus spins on its side, which puzzles many scientists.
13Neptune, the farthest planet, has the fastest winds recorded.
14Beyond Neptune lies a region full of icy objects.
15Pluto was reclassified as a dwarf planet in two thousand six.
16Comets grow glowing tails when they approach the Sun.
17Most asteroids travel in a belt between Mars and Jupiter.
18Light from the Sun takes eight minutes to reach the Earth.
19The guide said our solar system is one among billions.
20On the bus home, nobody stopped talking about space.