Astronomy Facts-Dialogue for Kids (Idaho Public Television)

Astronomy

Sep 19, 2006
2:00/1:00 MT/PT

If you're interested in

ASTRONOMY...

LOOK UP!!!

For thousands of years humans have been looking up at the sky, before we even knew the word "astronomy". We are still looking up because the sky is such a fascinating place and because we are learning more and more about it everyday. Let's stretch our imaginations as we explore:
Astronomy, the study of everything that
is or was in space beyond the Earth's atmosphere.

Astronomy History

Astronomers Tools

The Universe

Measurement in the universe

History Long ago people thought that the sun, and all the other planets, revolved around Earth. A man named Galileo proved in the 1600's that the Earth and the other planets revolved around the sun . He used a special tool called a telescope to look at the sky. Visit the TIME LINE of important events in astronomical history to learn more.

Here's more about Galileo's tool, the telescope, and the development of the the many different kinds of telescopes.

Learn about Arecibo, the largest single-dish radio telescope in the world.

What do observatories have to do with astronomy?

yellow shooting star

The Universe

How big is it?
When you look up at the night sky you are looking at the universe.
Everything is inside the universe, even us, and it is impossible to imagine how big the universe is. Special astronomers called cosmologists are trying to measure it. They analyze the light from a star with an instrument called a spectroscope. By studying the spectrum they can tell whether an object is moving away from Earth or toward Earth. Based on the information from this instrument, scientists have learned that the universe is still growing outward in all directions.

How old is it?
Scientists believe that over 15 billion years ago, a powerful explosion called the Big Bang set the universe into a motion which continues today. Scientists are not yet sure if the motion will stop, change direction, or keep going forever.

How do you measure distances in the universe?
Since distances are so huge in the universe astronomers need a measurement with a big scale. They use a unit of length called a light year which is the distance light can travel in one year. Light travels very fast, so in a year it can go 6,000,000,000,000 (6 trillion) miles, or 9,500,000,000,000 kilometers.

Galaxies

Galaxies are collections of billions of stars, gas, and dust held together by gravity. All stars belong to a galaxy and galaxies are huge. Our sun, Earth, and all the stars you see when you look at the night sky belong to the Milky Way Galaxy. Scientists estimate that there may be 10 billion stars in our galaxy and 50 billion galaxies in the universe. Galaxies are classified by their shape: spiral, elliptical or irregular. The Milky Way is spiral.

You, too, can Classify Galaxies if you dare...

What does a quasar have to do with a galaxy?

Stars

Life Cycles of Stars

FACT: The prefix "astro" means "star" in the Greek language.

Stars are large balls of gas that give off light. Scientists know that you can see about 3,000 stars with your naked eye. With powerful telescopes, scientists can see billions and billions of other stars.

How old is a star?
Did you know that stars vary in their size, color, and brightness? A star can be red, orange, yellow, white, or blue. Its color depends on its surface temperature, which is determined by its age and mass. Stars go through many stages in their lifetime. Some of the names for these stages are Nebula, Red Giant, Supernova, White Dwarf, Neutron Star and even Black Holes. Stars can shine for up to 10 billion years!

The Life Cycle of a Star the size of the sun

Famous Star Stats

The Life Cycle of a Star heavier than the sun

Our Solar System

The Roman word for the sun was "Sol" so, our solar system has something to do with the sun. The sun is the center of the solar system which includes nine planets, more than seventy moons, comets, asteroids, and other space objects that travel in paths around the sun. The sun is the biggest object in our solar system, yet it is a medium-sized star, and it will use up its energy and die in about 5 billion years! The sun is the reason why there is life on earth. It provides the light and heat energy that living things need to survive.

Did you know that the solar system is about 4.6 billion years old?

Did you know that if an object orbits the sun it is called a planet but if it orbits something instead of the sun it is called a moon?

Do you believe that there are over 30,000 asteroids?

There are so many interesting facts about the solar system that you'll have to go behind the scenes at these links:

Amazing
Sun Facts

Solar System Facts	Planets Update: Pluto no longer a Planet!	Comets	Astronomy for Kids
The Earth's Moon	Your age on different planets	Asteroids
The Earth	Your weight on different planets	Meteoroids	NASA's Planet Photojournal

Are Constellations real? Scorpio Constellation

The constellations are pictures of things that people have imagined in the stars for thousands of years. They created stories about how these pictures, or constellations, were created. Many of the constellations in the northern sky were found and named by the Greeks during the Greek Empire (about 50 BC to 480 AD). Other humans, besides the Greeks, developed their own stories. Learn more about these stories and the constellations they represent at Constellations , and Mayan astronomy.

Final Explorations for Amateur Astronomers
The GLOSSARY Out-of-this-world LINKS FOR KIDS Cosmic LINKS FOR TEACHERS RESOURCES