NASA's Juno spacecraft is nearing its suicidal rendezvous with Jupiter
NASA's Juno spacecraft is closing in on Jupiter and it has a new photo to prove it.
The Jupiter-bound satellite is expected to enter orbit around the huge planet on July 4, but it's already beamed back an image of the giant planet and some of its largest moons.
The new photo, taken on June 21, shows hints of Jupiter's bands of clouds along with the moons Ganymede, Io, Europa and Callisto clustered to the left of the large world.
You May Also Like
Soon, Jupiter will come into even better focus when Juno enters into orbit around the planet and starts beaming back images.
When the June 21 photo was taken, Juno was about 6.8 million miles from Jupiter. On July 4, Juno is expected to fly just 2,900 miles above the tops of the planet's clouds, just about the same distance as the diameter of the continental United States.
Juno, which was launched from Earth in August of 2011, is designed to learn more about Jupiter's atmosphere and evolution by studying its auroras and magnetic field. The spacecraft should make 37 close approaches through the course of its nearly two-year mission, giving scientists plenty of data to analyze.
This mission won't be easy on Juno. The radiation environment near Jupiter -- due to the unique inner workings of the massive planet -- is so intense that the spacecraft's instruments won't be able to function for very long in that part of space.
Mission managers have designed the craft's close approaches of Jupiter to minimize the harmful impacts of that radiation on Juno's hardware, but even so, the mission will only last for about 20 months because of the harsh environment.
"Over the life of the mission, Juno will be exposed to the equivalent of over 100 million dental X-rays," Rick Nybakken, Juno's project manager, said in a statement.
"But, we are ready. We designed an orbit around Jupiter that minimizes exposure to Jupiter’s harsh radiation environment. This orbit allows us to survive long enough to obtain the tantalizing science data that we have traveled so far to get,” Nybakken said.
The source of the radiation that will doom Juno is thought to lie beneath the planet's clouds, in a layer of hydrogen that is under "such incredible pressure it acts as an electrical conductor," NASA states on its website.
Scientists believe that the combination of this metallic hydrogen along with Jupiter's fast rotation -- one day on Jupiter is only 10 hours long -- generates a powerful magnetic field that surrounds the planet with electrons, protons and ions traveling at nearly the speed of light. The endgame for any spacecraft that enters this doughnut-shaped field of high-energy particles is an encounter with the harshest radiation environment in the solar system.
Earth-based tools are aiding Juno in its research mission.
For example, new photos taken by a telescope in Chile show the planet shining in infrared light. The images are part of a campaign aimed at mapping Jupiter more fully before Juno arrives next week.
“These maps will help set the scene for what Juno will witness in the coming months," said Leigh Fletcher, the team leader for these observations, in a statement.
Have something to add to this story? Share it in the comments.
Miriam Kramer worked as a staff writer for Space.com for about 2.5 years before joining Mashable to cover all things outer space. She took a ride in weightlessness on a zero-gravity flight and watched rockets launch to space from places around the United States. Miriam received her Master's degree in science, health and environmental reporting from New York University in 2012, and she originally hails from Knoxville, Tennessee. Follow Miriam on Twitter at @mirikramer.
