Because of the large distances involved, we can't run any wires between the Earth and space. So the only way to send information back and forth is to use radio waves. Just like a radio station broadcasts a signal which you can listen to using a radio, astronauts and people on Earth can broadcast information back and forth to each other. This information can be in any form, and now, the International Space Station can even support a connection to the internet this way. These days, astronauts can communicate with their families via email, and chat with the public on Twitter. Technology even allows astronauts to have video chats with their loved ones, as well as with schools.
Another popular method over the years has been ham radio. Astronauts can communicate with entire networks of amateur radio operators all over Earth!
Page last updated on June 24, 2015.