How Do We Communicate with Faraway Spacecraft?

When scientists and engineers want to send commands to a spacecraft in deep space, they turn to the Deep Space Network, NASA's international array of giant radio antennas used to communicate with spacecraft at the Moon and beyond. Operators at the Deep Space Network take commands, break them into digital bits, precisely aim these big antennas at the spacecraft, and send the commands to the spacecraft using radio waves.
The antennas of NASA's Deep Space Network are the indispensable link to robotic explorers venturing beyond
Earth. They provide the crucial connection for commanding our spacecraft and receiving their never-before-seen images and scientific information on Earth, propelling our understanding of the universe, our solar system and ultimately, our place within it.
Managed by NASA's Jet Propulsion Laboratory for the Space Communications and Navigation (SCaN) Program, based at NASA Headquarters within the Space Operations Mission Directorate, the Deep Space Network is what enables missions to track, send commands to, and receive scientific data from faraway spacecraft.