SCOTT SIMON, host:
This is WEEKEND EDITION from NPR News. I'm Scott Simon.
Coming up: Singing the blues of bluesman Jimmy Reed. But first, 30 years ago this week, NASA launched the Voyager 1 spacecraft into the deep, dark, unknown of the solar system. Over the past three decades, Voyager has sent back some of the finest glimpses of outer space that have made it less unknown. Pictures of Saturn's rings, towering volcanoes, and Jupiter's moon and the Earth itself, a tiny blue dot among glimmering white stars, data from outer space too.
(Soundbite of noise)
SIMON: That's the sound of signals the probe sent back in 1979. The Voyager 1 mission was intended to last for only five years. But today, Voyager 1 is the furthest man-made object in outer space - almost 10 billion miles away - three times as distant as Pluto. And it continues to sent back pictures and data as it makes its way boldly going where no robotic probe has gone before.
Ed Massey is the manager of NASA's Voyager Interstellar Mission. He joins us from NASA Jet Propulsion Laboratory in Pasadena.
Thanks for being with us, Mr. Massey.
Mr. ED MASSEY (Manager, Voyager Interstellar Mission, NASA): Glad to be here.
SIMON: And a naive question, how does Voyager move through space? I mean, how's it steered? What propels it?
Mr. MASSEY: Well, when it left Earth, it flew towards Jupiter, and Jupiter's gravity gave it a slingshot effect and it got another slingshot at Saturn. So it's going to continue at that speed in that direction, which has gone north toward interstellar space, unless something stops it.
SIMON: The thing that intrigues me about Voyager still sending back information is, I mean, hasn't the technology changed a lot in, you know, in the past 25 years? Is this like someone sending you a long-playing record?
Mr. MASSEY: It has changed a lot. For instance, now Voyager sends 160 bits of data per second, and some of newer spacecraft are sending a megabyte of data per second. Voyager has three computers that probably has less memory as your -than your camera card.
(Soundbite of laughter)
SIMON: What would you rank as some of the best - most noteworthy gifts that Voyager sent back to scientists on Earth?
Mr. MASSEY: Well, we discovered at Jupiter, for instance, this mini-turbulent storms, dozens of them, interacting like hurricanes. The biggest has been the Great Red Spot. We also saw volcanoes erupting from Jupiter's moon Io, which was the first time we've seen volcanoes anywhere except on Earth. And then at Saturn, we discovered the many, many intricacies of the rings. There were, at least, a couple of rings that we discovered because we had not been able to see those unless we were actually immersed there.
SIMON: In theory, do you have, and recognizing that in the previous answers you have has long been exhausted, do you have any handle on how long Voyager could keep functioning?
Mr. MASSEY: This is assuming that nothing else breaks.
Mr. MASSEY: We have enough power to go until the year 2020 or possibly slightly beyond that. Power is the limiting factor.
SIMON: Mr. Massey, keep watching the stars for us, sir.
Mr. MASSEY: We'll do that.
SIMON: Ed Massey is the manager of NASA's Voyager Interstellar Mission. He joined us from the Jet Propulsion Laboratory in Pasadena.
Voyager 1 was intended to not just gather information but offer a little too. In case the probe encounters life in another part of the universe, Voyager 1 carries a gold-plated record with some of the signature sounds of the Earth. Here's a sample.
(Soundbite of recording)
Secretary General KURT WALDHEIM (United Nations): As the secretary general of the United Nations, who represent almost all of the human inhabitants of the planet Earth, I send greetings on behalf of the people of our planet.
Unidentified Man #1: (Foreign language spoken)
Unidentified Woman #1: (Foreign language spoken)
Unidentified Woman #2: (French spoken)
Unidentified Man #2: Shalom.
Unidentified Man #3: (Foreign language spoken)
Unidentified Man #4: Hello from the children of planet Earth.
(Soundbite of screaming)
(Soundbite of wolf)
(Soundbite of heart beating)
Unidentified Woman: (Singing) (Foreign language spoken)
(Soundbite of song, "Johnny Be Good")