Exploring Space

Planets

Comets

The comet Kohoutek is a frozen ball of ice streaking through space. As it gets closer to the Sun, some of the ice melts and forms a beautiful tail of gas and dust.

Photography Credit: NASA Johnson Space Center (NASA-JSC)

This is the Stardust spacecraft. Scientists have sent it on a long journey to collect dust from a comet's tail and bring it back to Earth to study.

Photography Credit: NASA/JPL

Asteroids

Asteroids are chunks of rock in space that orbit the Sun. Some are as big as houses or even mountains. Scientists have named this asteroid Ida.

Photography Credit: NASA Jet Propulsion Laboratory (NASA-JPL)

Meteors

Meteors are fragments of rock—most no bigger than grains of sand—that fall from space to Earth. We call them “shooting stars” when they burn and glow as they streak across the night sky. This little rock, which is about two inches across, is a piece of an asteroid that fell all the way to Earth.

Photography Credit: JPL and NASA

Milky Way

There are billions of stars in the Milky Way Galaxy—including our own Sun.

Vocabulary

Activity

In addition to planets and stars, what are some of the other objects you could find in space?[anno: There are also asteroids, meteors, and comets in space.]

Where does the dust in a comet's tail come from?[anno: The dust in a comet's tail comes from the ice that had been frozen as part of the comet. As the comet gets closer to the Sun, part of it melts, releasing water and dust.]

Why do you think that scientists might be interested in studying the dust from a comet's tail?[anno: Answers will vary but could include that scientists are curious about what the dust is made of and how old it is.]