What are shooting stars?

Shooting stars, or meteors,
are the streaks of light you sometimes
see at night.
They are made by pea-sized bits of rocks or metals
called meteoroids, which fall from space
and burn in the Earth’s atmosphere.

What is Halley’s Comet?

Comets are huge clouds of gas and dust,
much bigger than the Earth,
with a rocky core a few kilometers across.
Halley’s comet is named after the English scientist
Edmond Halley (1656-1742),
Who worked out that its orbit around the Sun
brings it close to Earth every 76 years.

Why do we need the Sun?

The Sun is a star.
It is like a blowing ball of hot gasses
producing a vast amount of energy which streams
through space in waves of light and heat.
This energy is essential to life on Earth.
Without it our planet would be so cold and dark
for plants and animals to survive.

The Sun is about 150 million km from Earth.
The Sun is made of a gas called Helium.
Much of the Sun is made of a gas called Hydrogen.

What is a satellite?

A satellite is something that orbits a planet.
Until the Space age began,
the Earth’s only satellite was the Moon.
Now it also has many artificial satellites-
machines which orbit it,
doing all sorts of jobs.
Some satellites relay TV and telephone signals.
Some study the stars,
others the Earth and its weather.

Why do stars twinkle?

It is the Earth’s atmosphere that makes stars twinkle.
On its way to Earth, starlight passes through bands
of warm and cold air in the atmosphere.
These heat currents make the stars flicker.

Why does the Moon change shape?

The Moon is lit by the Sun
and doesn’t give any light of its own.
However the Sun only lights half of the Moon,
Leaving the other half dark and invisible.
We can only see one face or side of the Moon from Earth,
Because we see this face from different angles
During the 29 1/2 days the Moon takes to orbit Earth.
Sometimes the Sun lights all of the face of the Moon that we see.
At other times only part is lit.

Why does the Sun rise?

Although we can’t feel it,
The earth is always moving.
It orbits, or goes round, the Sun,
And this journey takes a whole year.
At the same time the Earth itself is spinning-
one whole spin every 24 hours.
As the Earth spins, the Sun comes into view
And it seems to move across the sky.
The Earth spins from West to east,
So the Sun is in the East when we first see it in the morning,
and in the West when it sets in the evening.