Illustration credit & copyright: NASA/JPL.
Launched on August 5, 2011 from Cape Canaveral Air Force Station (CCAFS), SLC-41 on an Atlas V 551 Juno, the second of NASA’s New Frontier spacecraft (the first being New Horizons) has been making her way out into the solar system en route to Jupiter. On January 13, 2016 Juno reached the milestone of becoming the most distant solar powered spacecraft at a distance of 493 million miles (793 km) beating out ESA’s famous Rosetta spacecraft still in orbit around Comet 67P.
With 1.74 billion miles (2.8 billion km) down and 19 million miles (31 million km) to go at 60,000 mph, Juno’s trip is almost over as the spacecraft is slated to reach Jupiter and become only the second spacecraft to orbit Jupiter (after the Galileo probe) on July 4, 2016 where it will then begin to study the evolution of the gas giant. Arrival (Earth Received Time) will occur around 20:35 PDT (JPL Time), 23:35 EDT and 03:35 UTC on the 5th. Speed of light travel time will be about 40 minutes from Earth to Jupiter so as the milestones come in to JPL they will be 40 minutes behind the true action time; AKA a 40 minute delay from when the event actually happens to when we get signal.
Though an amazing achievement, don’t expect another Saturn’s Cassini because JUpiter Near-polar Orbiter (Juno) will make only about 37 polar orbits over 20 months and is scheduled to plummet into Jupiter in February 2018 ending the mission.
With such a long travel time hopefully Juno has had some time to cool off because in Greco-Roman mythology, Jupiter isn’t exactly the monogamous type. It is said that Jupiter (Roman for the Greek Zeus) shrouded himself in clouds to hide his mischievous ways and the only one that could see his true nature was his wife, Juno. And Jupiter’s moons, well, most are named for his lovers and their children.
Like many spacecraft, Juno carries with it some dedications. First a small (2.8 X 2 inch) aluminum plaque from the Italian Space Agency with the image of Galileo and some words copied in his own handwriting from January of 1610 while discovering the first three moons of Jupiter which reads (translated from Italian of course),
“On the 11th it was in this formation, and the star closest to Jupiter was half the size than the other and very close to the other so that during the previous nights all of the three observed stars looked of the same dimensions and among them equally afar; so that it is evident that around Jupiter there are three moving stars invisible until this time to everyone.”
There are also three aluminum LEGO figurines onboard representing Galileo, Jupiter and Juno. Galileo holds Jupiter in one hand while in the other, a telescope. Jupiter is holding lightning bolts and his wife Juno holds a magnifying glass as she searches for truth.
NASA Juno mission: http://www.nasa.gov/mission_pages/juno/main/index.html
Southwest Research Institute Juno mission page: https://www.missionjuno.swri.edu/
JPL Juno: http://www.jpl.nasa.gov/missions/juno/
Where is Juno? http://www.nasa.gov/mission_pages/juno/where
LEGO figurines: http://www.jpl.nasa.gov/news/news.php?release=2011-241