Pioneering NASA Spacecraft Mark Thirty Years of Flight
08.20.07
PASADENA, Calif. - NASA's two venerable Voyager spacecraft are celebrating
three decades of flight as they head toward interstellar space. Their ongoing
odysseys mark an unprecedented and historic accomplishment.
Voyager 2 launched on Aug. 20, 1977, and Voyager 1 launched on Sept. 5, 1977.
They continue to return information from distances more than three times farther
away than Pluto.
Image right: Artist concept of the two Voyager spacecraft as they approach interstellar space. Image credit: NASA/JPL + Larger view+ Learn more about the terms used+ Blog: Voyager's Golden Record
+ Slide show: Planetary Tour
+ Voyager's Many Discoveries
"The Voyager mission is a legend in the annals of space exploration. It opened
our eyes to the scientific richness of the outer solar system, and it has pioneered
the deepest exploration of the sun's domain ever conducted," said Alan Stern, associate
administrator for NASA's Science Mission Directorate, Washington. "It's a testament to
Voyager's designers, builders and operators that both spacecraft continue to deliver
important findings more than 25 years after their primary mission to Jupiter and
Saturn concluded."
During their first dozen years of flight, the Voyagers made detailed explorations of
Jupiter, Saturn, and their moons, and conducted the first explorations of Uranus and
Neptune. The Voyagers returned never-before-seen images and scientific data, making
fundamental discoveries about the outer planets and their moons. The spacecraft revealed
Jupiter's turbulent atmosphere, which includes dozens of interacting hurricane-like storm
systems, and erupting volcanoes on Jupiter's moon Io. They also showed waves and fine
structure in Saturn's icy rings from the tugs of nearby moons.
For the past 18 years, the twin Voyagers have been probing the sun's outer heliosphere
and its boundary with interstellar space. Both Voyagers remain healthy and are returning
scientific data 30 years after their launches.
Voyager 1 currently is the farthest human-made object, traveling at a distance from the
sun of about 15.5 billion kilometers (9.7 billion miles). Voyager 2 is about 12.5 billion
kilometers (7.8 billion miles) from the sun. Originally designed as a four-year mission to
Jupiter and Saturn, the Voyager tours were extended because of their successful achievements
and a rare planetary alignment. The two-planet mission eventually became a four-planet grand
tour. After completing that extended mission, the two spacecraft began the task of exploring
the outer heliosphere.
"The Voyager mission has opened up our solar system in a way not possible before the Space
Age," said Edward Stone, Voyager project scientist at the California Institute of Technology, Pasadena, Calif. "It revealed our neighbors in the outer solar system and showed us how much
there is to learn and how diverse the bodies are that share the solar system with our own planet Earth."
In December 2004, Voyager 1 began crossing the solar system's final frontier. Called the
heliosheath, this turbulent area, approximately 14 billion kilometers (8.7 billion miles) from the sun, is where the solar wind slows as it crashes into the thin gas that fills the space between
stars. Voyager 2 could reach this boundary later this year, putting both Voyagers on their final
leg toward interstellar space.
Each spacecraft carries five fully functioning science instruments that study the solar wind, energetic particles, magnetic fields and radio waves as they cruise through this unexplored
region of deep space. The spacecraft are too far from the sun to use solar power. They run on
less than 300 watts, the amount of power needed to light up a bright light bulb. Their long-lived radioisotope thermoelectric generators provide the power.
"The continued operation of these spacecraft and the flow of data to the scientists is a testament
to the skills and dedication of the small operations team," said Ed Massey, Voyager project
manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. Massey oversees a team of
nearly a dozen people in the day-to-day Voyager spacecraft operations.
The Voyagers call home via NASA's Deep Space Network, a system of antennas around the world.
The spacecraft are so distant that commands from Earth, traveling at light speed, take 14
hours one-way to reach Voyager 1 and 12 hours to reach Voyager 2. Each Voyager logs approximately
1 million miles per day.
Each of the Voyagers carries a golden record that is a time capsule with greetings, images and
sounds from Earth. The records also have directions on how to find Earth if the spacecraft is recovered by something or someone.
NASA's latest outer planet exploration mission is New Horizons, which is now well past Jupiter
and headed for a historic exploration of the Pluto system in July 2015.
For a complete listing of Voyager discoveries and mission information, visit the Internet at:
http://www.nasa.gov/voyager and
http://voyager.jpl.nasa.gov/ .
JPL manages the Voyager mission for NASA's Science Mission Directorate. NASA's Lewis Research Center (now Glenn Research Center) in Cleveland, Ohio, managed the launches of the Voyager spacecraft.
Media contact: Carolina Martinez/Jane Platt 818-354-9382/0880
Jet Propulsion Laboratory, Pasadena, Calif.
carolina.martinez@jpl.nasa.gov, jane.platt@jpl.nasa.gov
Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown@nasa.gov
2007-092