CAPE CANAVERAL, Fla. — After days of silence, NASA has heard from Voyager 2 in interstellar space billions of miles away.

Flight controllers accidentally sent a wrong command nearly two weeks ago that tilted the spacecraft’s antenna away from Earth and severed contact.

NASA’s Deep Space Network, giant radio antennas across the globe, picked up a “heartbeat signal,” meaning the 46-year-old craft is alive and operating, project manager Suzanne Dodd said in an email Tuesday.

The news “buoyed our spirits,” Dodd said. Flight controllers at the Jet Propulsion Laboratory in California will now try to turn Voyager 2’s antenna back toward Earth.

If the command doesn’t work — and controllers doubt it will — they’ll have to wait until October for an automatic spacecraft reset. The antenna is only 2% off-kilter.

“That is a long time to wait, so we’ll try sending up commands several times” before then, Dodd said.

Voyager 2 rocketed into space in 1977, along with its identical twin Voyager 1, on a quest to explore the outer planets.

Still communicating and working fine, Voyager 1 is now 15 billion miles (24 billion kilometers) from Earth, making it the most distant spacecraft.

Anthony Leone contributed to this article.