NASA's Space Place
What’s in Space?
By Linda Hermans-Killam
National Aeronautics and Space Administration
When you look up at the night sky, you see stars and sometimes the moon and the brighter planets. Away from city lights, on a clear night, you might see the beautiful band of the Milky Way stretching across the sky.
Is there anything else up there in space?
There are many beautiful, strange and mysterious objects in space. We are lucky that we now have large telescopes to help us see far into space.
With telescopes, we can get a much better view of the planets and moons in our solar system. By using special telescopes, scientists can get a better view of our sun. We can see that the sun is not smooth and we can see many features on the sun’s surface. Never look at the sun with your eyes or through a telescope. The sun’s intense light can damage your eyes.
Looking farther away, we can see other stars. Some are like our sun, while others are much larger or smaller. Stars come in different colors. We do not see the colors of the stars when we look up into the night sky because they are too dim. But telescopes can collect more light and can show us the colors of the stars.
Telescopes show us the giant clouds of gas and dust where stars are born. Stars form when parts of these clouds collapse and get hot enough to make their own light. Our own solar system started in one of these clouds. There are many of these clouds in space.
When a star runs out of fuel, part or all of the star expands into space. Some of the stars shed their outer layers while the largest stars explode. The material from these stars help form new clouds where new stars will form.
Stars, planets and clouds of gas are collected into galaxies where they are held together by gravity. Galaxies are huge, and can have billions of stars in them. We live in a large galaxy called the Milky Way. As we look even farther into space we see more and more galaxies. There are billions of galaxies in space, each holding billions of stars.
The universe is a very big place to explore and many of its secrets are yet to be discovered!
To learn more about galaxies—including our very own Milky Way—visit http://spaceplace.nasa.gov/galaxy
The Orion Nebula as imaged by the Spitzer Space Telescope.