NASA launches mission to Jupiter
Aug 5, 2011
NASA has launched a mission to Jupiter that will shed light on the origin and inner structure of the largest planet in our solar system. The $1.1bn Juno probe was launched today from Cape Canaveral, Florida, at 12.25 p.m. local time and will now begin a five-year journey to the planet.
Juno, named after the wife of the Roman god Jupiter, is the second probe to orbit Jupiter. The first was NASA's Galileo satellite, which launched in 1989 to the planet and its moons. Other craft have also since travelled near Jupiter on their way to other planets such as the Saturn-bound Cassini-Huygens mission, which was launched in 1997 by NASA and the European Space Agency.
While these missions did not deviate far from the equator of Jupiter, Juno will enter a highly elliptical orbit around the poles of the planet. "This will allow us to gain access to the entire volume of space around Jupiter for the first time," says Jack Connerney, from NASA's Space Goddard Flight Center, who is lead instrument scientist of the mission.
Looking for a lore
While in orbit, Juno will study the planet's atmosphere, gravity and magnetic fields as well as attempt to answer how the planet formed and whether it has a rocky core. It will do this via nine onboard instruments, which include a camera, magnetometer, microwave radiometer and spectrometer.
Jupiter's magnetic field is around 20,000 times greater than that on Earth, producing the largest magnetosphere of any planet in the solar system. It will be mapped in unprecedented detail by Juno, possibly revealing details about its origin. "We are sending to Jupiter the most capable and accurate magnetic observatory to ever venture into deep space," adds Connerney.
Power from the Sun
Juno will use three solar arrays for propulsion, making it the furthest distance a solar-powered probe has travelled in the solar system. Previous missions such as Cassini-Huygens or the Pioneer craft generated power via the heat released from the decay of radioactive particles.
Juno will operate for a year, completing 32 orbits around Jupiter, which each take around 11 days. The probe will then be made to crash into the planet. In addition to the nine instruments, Juno is also carrying a plaque, provided by the Italian Space Agency, dedicated to the famous astronomer Galileo Galilei, as well as three 3.8 cm-tall LEGO figurines of Galileo, the Roman god Jupiter and his wife Juno.
The mission is the second spacecraft of NASA's New Frontiers programme. The first was the Pluto New Horizons mission, which launched in January 2006 and is scheduled to reach Pluto's moon Charon in 2015.
About the author
Michael Banks is news editor of Physics World