Stars do not drift alone. They gather in their billions into galaxies, vast pinwheels bound by gravity. Ours is the Milky Way, and the gaps between its stars are so huge we measure them in the distance light itself travels in a year.
A galaxy is a vast collection of billions of stars held together by gravity, and our galaxy is the Milky Way. Distances between stars are measured in light-years, the distance light travels in one year.
A galaxy is a huge collection of billions of stars held together by gravity. Our galaxy is the Milky Way, which contains the Sun.
A light-year is a distance, not a time. The universe contains billions of galaxies.
See the Milky Way and how far apart its stars are in light-years.
Four quick checks. Each correct answer earns XP and lights this skill on your star map.
A galaxy is...
Our galaxy is called the...
A light-year is...
A light-year is a unit of...
Billions of stars make a galaxy, and the huge gaps are measured in light-years.
A light-year is a distance, not a time. It is how far light travels in one year. Our Sun is just one star in the Milky Way, which is itself one of billions of galaxies.
Unlocks once the four checks above are done. Worth more XP, written in the style of Paper 2.
What holds the billions of stars in a galaxy together?
A student says a light-year is the time light takes to cross a galaxy. This is wrong because a light-year is a...
The Sun is one star in...
Galaxies and light-years are mapped. Keep the chain going.