Voyager 1 set to leave solar system
PASADENA, Calif.—Thirty-five years after leaving Earth, Voyager 1 is reaching for the stars.
Sooner or later, the workhorse spacecraft will bid adieu to the solar system and enter a new realm of space—the first time a manmade object will have escaped to the other side.
“We’re anxious to get outside and find what’s out there,” he said.
When NASA’s Voyager 1 and Voyager 2 first rocketed out of Earth’s grip in 1977, no one knew how long they would live.
Now, they are the longest-operating spacecraft in history and the most distant—at billions of miles from Earth but in different directions.
Tomorrow marks the 35th anniversary of Voyager 1’s launch to Jupiter and Saturn. It now is flitting around the fringes of the solar system, which is enveloped in a giant plasma bubble.
This hot and turbulent area is created by a stream of charged particles from the sun.
Outside the bubble is a new frontier in the Milky Way—the space between stars. Once it plows through, scientists expect a calmer environment by comparison.
When that would happen is anyone’s guess. Voyager 1 is in uncharted celestial territory.
One thing is clear: the boundary that separates the solar system and interstellar space is near, but it could take days, months, or years to cross that milestone.
Voyager 1 currently is more than 11 billion miles from the sun. Twin Voyager 2, which celebrated its launch anniversary two weeks ago, trails behind at nine billion miles from the sun.
They’re still ticking despite being relics of the early Space Age.
Each only has 68 kilobytes of computer memory. To put that in perspective, the smallest iPod—an 8-gigabyte iPod Nano—is 100,000 times more powerful.
Each also has an eight-track tape recorder. Today’s spacecraft use digital memory.
The Voyagers’ original goal was to tour Jupiter and Saturn, and they sent back postcards of Jupiter’s big red spot and Saturn’s glittery rings.
They also beamed home a torrent of discoveries: erupting volcanoes on the Jupiter moon, Io; hints of an ocean below the icy surface of Europa (another Jupiter moon); and signs of methane rain on the Saturn moon, Titan.
Voyager 2 then journeyed to Uranus and Neptune. It remains the only spacecraft to fly by these two outer planets.
Voyager 1, meanwhile, used Saturn as a gravitational slingshot to catapult itself towards the edge of the solar system.
These days, a handful of engineers diligently listen for the Voyagers from a satellite campus not far from the NASA Jet Propulsion Laboratory, which built the spacecraft.
The control room, with its cubicles and carpeting, could be mistaken for an insurance office if not for a blue sign overhead that reads “Mission Controller” and a warning on a computer: “Voyager mission critical hardware. Please do not touch!”
There are no full-time scientists left on the mission, but 20 part-timers analyze the data streamed back.
Since the spacecraft are so far out, it takes 17 hours for a radio signal from Voyager 1 to travel to Earth.
For Voyager 2, it takes about 13 hours.
Cameras aboard the Voyagers were turned off long ago. The nuclear-powered spacecraft—about the size of a subcompact car—still have five instruments to study magnetic fields, cosmic rays, and charged particles from the sun known as solar wind.
They also carry gold-plated discs containing multilingual greetings, music, and pictures—in the off-chance that intelligent species come across them.