Download Beyond the Solar System By Patti Hutchison ANSWER THE

Beyond the Solar System
By Patti Hutchison
ANSWER THE QUESTIONS ON THE NEXT
PAGE WHEN YOU’RE DONE READING THIS
ARTICLE.
PURPOSE: Introduce you to the study of the
GALAXY beyond the solar system !!!
Caption: Barred spiral galaxy NGC 1300 photographed by Hubble telescope.
Our solar system extends billions of miles from Earth. But there is still something bigger. It is
the Milky Way, our galaxy. But wait, there's something even bigger than that- the universe!
There are billions of galaxies in space. A galaxy is a group of stars, gas, and dust that are bound
together by gravity. If you look into the sky on a dark night, you can see our galaxy, the Milky
Way. It is a shimmering belt that stretches across the sky. The Milky Way contains the solar
system we live in.
As a galaxy, the Milky Way is actually a giant. Its diameter is about 100,000 light years. A light
year is the distance that light travels in one year. A light year is about 9.5 trillion kilometers or
about 6 trillion miles. Our solar system is about 4.6 billion years old. Our sun is a young star.
Scientists think the Milky Way galaxy may be about 14 billion years old.
The smallest galaxies contain only a few hundred thousand stars. The largest can contain
trillions of stars. Galaxies bump into each other every so often. The Milky Way has had other
galaxies pass through it. But there is no danger; the stars are so far apart that a collision is not
likely to happen.
Galaxies come in different shapes. There are spiral, elliptical, and irregular shapes. About half
the galaxies in the universe are spiral galaxies. A spiral galaxy looks like a twirling octopus. In
the "arms" of the galaxy, new stars are formed. Some of them are very large. They cause the
surrounding clouds of dust to glow brightly, also. Spiral galaxies are beautiful to see.
New stars are not formed in elliptical galaxies. The stars in them were formed many years ago.
They are often close together, making the middle of the galaxy glow very brightly. If there
were any planets in an elliptical galaxy, it would never be night. The sky would be bright all
the time.
Any galaxy that is not spiral, elliptical, or lenticular is said to be irregular. Irregular galaxies
come in many shapes and sizes. They have very little organization. Scientists think some
galaxies are irregular because some event has disturbed them. Others just lack the
organization and the rotation of a spiral galaxy.
The universe is made up of billions of galaxies. The galaxies cluster together in groups. If you
could look at the whole universe at once, it would look like a spider web. Between the
galaxies, space is almost completely empty. Tiny atoms are hundreds of miles apart.
No one knows how big the universe actually is. Scientists are constantly trying to measure it.
They do know, however, that it is expanding all the time. Space missions travel farther and
farther into space. Will they find life somewhere else in the universe?
1. What is a galaxy?
2. Other galaxies have passed through the
Milky Way.
False
True
3. A galaxy with twirling arms is called:
A spiral galaxy
An elliptical galaxy
A lenticular galaxy
4. Where are new stars formed?
In the arms of a spiral galaxy
In an elliptical galaxy
Neither a nor b
5. What kind of galaxy does not form new
stars?
Spiral
Elliptical
Irregular
6. What is the space between galaxies like
in the universe?
7. We live in the ______.
The Local galaxy
The Milky Way galaxy
Orion galaxy
Andromeda galaxy
8. The Milky Way is a small galaxy.
False
True
9. The Milky Way is described as ______.
An irregular galaxy
A barred spiral galaxy
A spiral galaxy
10. How big is the Milky Way galaxy?
6 trillion miles across
9.5 trillion kilometers across
100,000 light years across
11. Our solar system is in the middle of the
galaxy.
False
True
12. How old is the Milky Way galaxy?
14 billion years old
10 billion years old
4.6 billion years old