Comet

space · icy · tails

Cosmic snowball. A comet's core, called the nucleus, is a loose mix of ice, dust, and small rocky bits, ranging from a few hundred meters to tens of kilometers across.

Sun makes it glow. When a comet passes close to the Sun, it warms up and releases gases. This creates a fuzzy cloud called a coma around the nucleus.

Super long tail. Solar wind and sunlight blow gas and dust off the comet, forming a tail that can stretch more than the distance from Earth to the Sun!

Visible to your eyes. If a comet is bright and close enough, you can see it without a telescope, sometimes stretching up to 30 degrees across the sky.

Ancient sky visitors. People from many cultures and religions have watched and recorded comets since ancient times.