Download Which Constellation is Which?

Objective – I can describe the appearance and apparent motion of groups of stars in the night sky.
Constellations
You probably know some constellations. The Big Dipper looks like a giant pot with a
long handle. Orion is named after a great hunter. You can see his belt, marked by three
bright stars. Constellations are imaginary pictures in the sky.
The stars look like they are all the same distance away. That’s not true. The stars in the
sky are different distances from Earth.
Which Constellation is Which?
When you look up at the sky, you may see shapes. Ancient stargazers created these
shapes. They are the constellations. They are named after people, animals, and things
that were important to them
You can use a star chart that shows where stars appear in the sky. As the night passes,
these shapes seem to move through the sky. It’s Earth that’s moving, not the Sun and
stars. It’s rotating on its axis.
You can only see the brightest stars with the naked eye. Look at the stars through
binoculars or a telescope. Thousands of fainter stars can be seen. You can no longer
see the shapes of constellations.
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Objective – I can describe the appearance and apparent motion of groups of stars in the night sky.
Do Constellations Always Look the Same?
The Earth revolves around the Sun. This is why you see different constellations
through the year.
 In the summer, we can’t see Orion because it is between the Earth and Sun. It is
daylight.
 Six months later we can see Orion. It is on the side of Earth away from the Sun.
People in the Southern Hemisphere see different constellations than people in the
Northern Hemisphere.
Southern Hemisphere Constellations
Northern Hemisphere Constellations
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Objective – I can describe the appearance and apparent motion of groups of stars in the night sky.
Constellations shapes also change. It takes thousands of years for changes to be seen. They will
look different in a hundred thousand years.
Big Dipper – 100,000 years ago
Big Dipper – Today
Big Dipper – In 100,000 years
How Do Astronomers Use Constellations?
Astronomers divide the sky into 88 constellations. Astronomers name objects after their
constellation. The Andromeda galaxy and the Orion nebula are examples. Earth sometimes passes
through showers of meteors. The showers are named after the constellations from which they seem
to fall. The Perseids and the Geminids are two examples.
What Are the Constellations of
the Zodiac?
The Babylonians noticed the Sun’s
position in the sky changes through
the year. They divided the stars
along the Sun’s path into twelve
constellations. We call these twelve
the constellations of the zodiac.
(There are really thirteen!)
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Objective – I can describe the appearance and apparent motion of groups of stars in the night sky.
The constellation Ophiuchus (the Serpent Bearer) is the thirteenth.
The Moon and the planets appear to move through the constellations of the
Zodiac. Here’s what the Moon might look like travelling through Leo.
May 13th
May 15th
May 17th
Look at Saturn. We would say, “Saturn is in Leo.” Over six weeks, Saturn moves through Leo.
When you see a planet, you will a couple of things. First, it will be brighter than the stars around it.
And, it will not twinkle like the stars around it.
Feb 9th
Jan 16th
Mar 1st
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