Artist illustration of Juno as it approaches Jupiter. (NASA)
It took a while — almost five years since launch — but the Juno spacecraft is now at Jupiter and orbiting the giant planet. A 35-minute rocket burn to slow Juno down from its record-breaking 130,000 mph entry speed led to a successful insertion into orbit just minutes before midnight, making it another July 4th NASA spectacular.
During its mission, Juno will circle the planet 37 times, dipping as low as 2,600 miles above the planet’s upper clouds of ammonia and water. Primary goals of the mission are to determine whether Jupiter has a solid rocky core or is made up of gases all the way through, to learn about its extraordinarily powerful magnetic forces, and to determine better the components of those upper clouds and what might lie beneath them.
The overriding purpose is to better understand how Jupiter — the first planet formed in our solar system — came to be, and consequently how our solar system was formed. Considering that Jupiter contains more matter than the rest of the solar system planets, moons, asteroids and comets combined, it clearly is the place to look to understand the origins ...