Planet Jupiter In Focus: NASA's Juno Mission Prepares For July 4 Flyby

Anya Wassenberg

Planet Jupiter will come into sharper focus on July 4 as NASA's Juno spacecraft enters into its orbit at the closest point ever attempted. The space agency is planning a series of 37 flybys of the giant planet to set a new record, but the ambitious mission does not come without risk.

On July 4, the Juno mission will pass within 2,900 miles, or 4,667 kilometers, of Jupiter's cloud cover. The last time a spacecraft got anywhere near this close to Jupiter was in 1974 when the NASA Pioneer 11 mission got within 27,000 miles of the giant planet.

The spacecraft's main engines will turn on to guide Juno into a polar orbit in a move the National Geographic calls "a dramatic 35-minute insertion maneuver." The Juno spacecraft is about the size of a basketball court and as of today, the mission has some 8.6 million miles or just under 14 million kilometers to go before it reaches Jupiter.

Jupiter is a gaseous planet with a turbulent surface where the winds can reach 400 miles per hour or more. Combined with a cloudy atmosphere, the winds create bands where there is intense particle radiation. The Juno spacecraft will circle the planet from pole to pole, cutting through to the constant cloud cover to study Jupiter's auroras. The data collected will help NASA scientists to better understand Jupiter's structure and atmosphere, and in turn its evolution as a planet.

NASA's Juno Mission is expected to spend up to 20 months studying Jupiter, collecting data relating to its origins, magnetosphere, or the planet's area of magnetic influence. Understanding Jupiter will help astronomers better comprehend the evolution of our own planet as well as providing clues to the origins of our solar system. Juno will dive towards the clouds about every two weeks, taking measurements with a series of eight instruments.

"Jupiter's charged particle radiation belts are the most energetic and intense in the solar system."

"Over the life of the mission, Juno will be exposed to the equivalent of over 100 million dental X-rays. 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."

[Image via NASA/JPL-Caltech]