Wittier than a wiley wizard?
More powerful than an apatosaurus?
Able to sweep across the whole sky without a sound?

Awesome as her powers are, however, no superhero can match what ordinary humans have done to solve one really big problem of space exploration. How ever do we communicate with the tiny spacecraft we send out to explore deep, dark space and strange other worlds?

The answer is . . . (drum roll here, please) the

The enormous antennas of the Deep Space Network are so sensitive they can hear what amounts to a tiny whisper from millions, or even billions, of miles away.

Carried on this whisper are beautiful images of planets, moons, asteroids, and comets.

This world map shows the three locations of the Deep Space Network's antennas. As Earth rotates on its axis, a spacecraft way out in space will be able to "see" at least one set of antennas. Each of the three locations has several antennas for tracking different spacecraft at the same time.

The largest of these dish antennas is 70 meters (about 230 feet) across. The movable part of the antenna weighs 3000 tons (6 million pounds). Even though it is like steering something the size of a soccer field loaded with 50,000 screaming fans, the antenna can be pointed so accurately that it could exactly target a soccer ball two miles away.

The spacecraft transmitter that sends the signal to Earth is about as powerful as the little light bulb in your refrigerator. By the time it reaches Earth, the spacecraft signal delivers only 0.000000000000000003 watts of power to the 70-meter antenna. But the antenna can still detect it!

It is very hard to imagine how weak that signal is. Suppose you spent the time shown in the first column of the chart below gathering and storing up all the energy the 70-meter antenna collects from this tiny signal. The total energy saved up would light a standard 4-watt Christmas tree bulb for only as long as the time shown in the second column.