Communications System How does NASA communicate with spacecraft?

What are radio waves?

Radio waves are part of a larger group of waves classified all together as electromagnetic radiation. This large group of waves is broken down into smaller groups based upon their frequencies and wavelengths. Two examples of electromagnetic radiation (other than radio waves) are:

• Light -- which is the group of electromagnetic radiation you can see with your eyes
• X-rays -- which are a group from a higher frequency and they are what is used by doctors to see inside of you

Below is an illustration of how electromagnetic radiation is broken down into groups. The section that covers radio waves is marked Radio Frequencies. The list of examples on the left is there to give you an idea of how long the wavelength is for that type of wave.

Illustration from the Athena project's On line activity: The Electromagnetic Spectrum. http://www.athena.ivv.nasa.gov/curric/space/lfs/emspectr.html

How is data put on radio waves?
What is frequency?
What is wavelength?
Is there energy in space?

How are frequency and wavelength related?
More about radio waves and electromagnetic radiation.
How does reflection affect radio waves?
What is electromagnetic radiation?

How do you make a radio wave?
What makes EM radiation?
What other forms of energy does a spacecraft releases into space?