Echo satellite

So, an echo satellite is like a big mirror in space that reflects radio signals. You know how when you shout in a big empty room, you hear your voice echo back to you? That's because the sound waves bounce off the walls and come back to you.

Well, scientists wanted to do something like that, but with radio waves. They wanted to bounce radio signals off a satellite and have them come back to Earth. This would help them study the Earth's atmosphere and ionosphere.

So, in the 1960s, they launched a big balloon into space with a metal coating on it called Mylar. This balloon was called Echo 1. It was like a giant shiny balloon in space that reflected radio waves back to Earth.

Later on, they launched another satellite called Echo 2. This one was even bigger than Echo 1 and was made of a super thin plastic material. It was so big that people on Earth could see it with their naked eyes as it passed overhead.

The echo satellites were important because they helped scientists learn more about how radio waves travel through the atmosphere and how the ionosphere affects radio communications.

So, basically, an echo satellite is like a giant mirror in space that bounces radio signals back to Earth so scientists can study them.