Before the advent of personal computers and long before the Internet…I used to own several telescopes. I’d spend hours out in the cold winter nights taking pictures thru these scopes that I’d later develop in my photo lab. But all those hours combined couldn’t produce a picture as good as the ones you can download over the Internet in just a few seconds. These pictures are from the Hubble Telescope.

The Hubble Heritage Project is devoted to information on the Hubble Telescope. There are some truly amazing pictures of our universe here. Many people don’t realize what’s really in the night sky. Because of the Hubble and several other specialized telescopes, we’re just beginning to understand the universe that surrounds us.

The Hubble is a time machine. Not in the “Dr. Who” sense, but it really does look back in time. When you look at the night sky, some of the stars you’re seeing might not even exist anymore. But you continue to see them. How can this be? It’s because you’re looking at them as they once were, not as they are now. They are located so far away that their light can take millions of years to reach us. The nearest star, Proxima Centauri, is about 4.3 light-years away. That’s almost 26 trillion miles.

Light from this star takes 4.3 years to reach us. And this is the nearest star. The Hubble Telescope has found objects whose light has taken 13 billion years to reach us!

It’s hard to imagine this time frame. Light travels about 186,000 miles a second. Sound is a little easier to grasp. Sound travels at approximately 750 miles an hour. Ever wonder how far away a lightning strike is? Just time the interval between the flash and the sound of thunder. Each second sound travels about 1/5 of a mile. So if you hear the thunder 7 seconds after the flash, the strike was about 1.4 miles away.

The loudest sound ever recorded was when Krakatoa (volcanic Island) blew up in 1883. The explosion was heard on the island of Rodrigues 3,000 miles away. It took four hours for the sound to get there.

The distance to the stars is so great that the light we see today could have died out millions of years ago. Yet, we’re still seeing it. The composition of this light can tell astronomers what a star is made of. All elements have unique signatures. The shifting of the frequencies of these signatures tells us if the star is moving towards us, or away. This is called the Doppler Effect. As an object moves towards you, the frequency of its light is shifted higher. As it moves away, it’s shifted lower.

This effect can be observed on the Earth too. Listen to a racecar’s engine as it approaches or a train whistle. The pitch (frequency) of its sound will increase as it nears, then decrease as it passes you. The faster it’s moving, the greater the change in pitch.

Your computer can be used to explore the heavens right from your desktop. Pictures from telescopes around the world (and in space) are at your fingertips. Here’s a website with a virtual telescope. http://skys.gsfc.nasa.gov/. Just enter the object you’d like to see and the virtual telescope will provide images taken by professional telescopes. This sure beats standing out in the cold to get a glimpse of what was often just a smudge in the eyepiece. Where was the Internet when I needed it?