Monday, August 20, 2012
Happy 35th, Voyager 2. Still Going Strong!
The above image shows the Voyager 2 spacecraft being launched on August 20, 1977, from the NASA Kennedy Space Center at Cape Canaveral in Florida, atop a Titan/Centaur rocket. Image Credit: NASA/JPL
August 20th marks the 35th anniversary of the launch of NASA's Voyager 2 spacecraft, the first Voyager spacecraft to launch, on a journey that would make it the only spacecraft to visit Uranus and Neptune and the longest-operating NASA spacecraft ever. Voyager 2. Its twin, Voyager 1, launched 16 days later on September 5, 1977 and both are still going strong, hurtling farther and farther away from our sun. Voyager mission managers eagerly anticipate the day when both spacecraft pass through the barrier separating interplanetary and interstellar space.
The data from the Voyagers turned Jupiter and Saturn into full, tumultuous worlds, their moons from faint dots into distinctive places, and gave us our first up-close glimpses of Uranus and Neptune. The mission team cannot wait for learn what lies beyond the boundary of our solar system.
Voyager 2 became the longest-operating spacecraft on August 13, 2012, surpassing Pioneer 6, which launched on December 16, 1965, and sent its last signal back to NASA's Deep Space Network on December 8, 2000. (It operated for 12,758 days.)
The mission team eagerly awaits the entry of the two Voyagers into interstellar space and have recently seen changes from Voyager 1 in two of the three observations that are expected to be different in interstellar space. The prevalence of high-energy particles streaming in from outside our solar system has jumped, and the prevalence of lower-energy particles originating from inside our solar system has briefly dipped, indicating an increasing pace of change in Voyager 1's environment. Voyager team scientists are now analyzing data on the direction of the magnetic field, which they believe will change upon entry into interstellar space.
Notable discoveries by Voyager 2 include the puzzling hexagonal jet stream in Saturn's north polar region, the tipped magnetic poles of Uranus and Neptune, and the geysers on Neptune's frozen moon Triton. Although launched second, Voyager 1 reached Jupiter and Saturn before Voyager 2, first seeing the volcanoes of Jupiter's moon Io, the kinky nature of Saturn's outermost main ring, and the deep, hazy atmosphere of Saturn's moon Titan. Voyager 1 also took the mission's last image: the famous solar system family portrait that showed our Earth as a pale blue dot.
Voyager 2 is about 9 billion miles (15 billion kilometers) away from the sun, heading in a southerly direction. Voyager 1 is about 11 billion miles (18 billion kilometers) away from the sun, heading in a northerly direction. For the last five years, both spacecraft have been exploring the outer layer of the heliosphere, the giant bubble of charged particles the sun blows around itself.
The mission team monitor Voyager 1 and 2 daily. And according to the team's data, the spacecraft are in great shape for having flown through Jupiter's dangerous radiation environment and having to endure the chill of being so far away from our sun.
The team has been carefully managing the use of power from the continually diminishing energy sources on the two spacecraft. The team members estimate that the two spacecraft will have enough electrical power to continue collecting data and communicating it back to Earth through 2020, and possibly through 2025. While no one really knows how long it will take to get to interstellar space, Voyager scientists think we don't have long to wait. And, besides, the first 35 years have already been a grand ride.
And now. The mission particulars...
The Voyager spacecraft were built by the Jet Propulsion Laboratory in Pasadena, California (JPL), which continues to operate both. JPL is a division of the California Institute of Technology (Caltech). The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington.
For more information about the Voyager spacecraft, visit: http://www.nasa.gov/voyager and http://voyager.jpl.nasa.gov