In August 2011, NASA's Juno spacecraft was sent to orbit Jupiter. The probe cost $1 billion and took five years to travel over 415 miles to reach the fifth planet from the sun. When the spacecraft finally settled into Jupiter's orbit, it finally started sending back photos of the gas giant and the results have been stunning.
Juno reached Jupiter of the Fourth of July in 2016. Juno performed "a suspenseful orbital insertion maneuver" to slow itself and enter Jupiter's orbit. It then slipped into place with plans to stay there for the next 20 months, and circle the planet 37 times.
In order to minimize its time inside Jupiter's intense radiation belts, Juno has been swinging close to Jupiter every two months. The radiation belts can damage Juno's electronics. Juno recently completed one of these cycles and sent us back a fresh glimpse into the mysteries of the universe.
The stunning photos (like this photo of Jupiter's south pole) show the planet like we've never seen it before. Prior, Juno cycles sent back photos of weird cloud formations and auras around the planet. We're learning quite a lot!
"Every time we get near Jupiter’s cloud tops, we learn new insights that help us understand this amazing giant planet," said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio. For example, images from prior flybys have revealed that "Jupiter's magnetic fields are more complicated than originally thought."
Additionally, NASA has reported that, "Observations of the energetic particles that create the incandescent auroras suggest a complicated current system involving charged material lofted from volcanoes on Jupiter's moon Io." Jupiter has secrets that Juno is starting to spill!
Furthermore, the reason for the gas giant's signature stripes and swirls goes deep. Per NASA, "the belts and zones that give the planet's cloud tops their distinctive look extend deep into the its interior." Juno isn't holding back in the information it's revealing.
Jupiter, the largest planet in the solar system, was discovered by Galileo in 1610. The gas giant's magnetic fields are stronger than any other planet and regularly give off a blast of radioactive energy that's more than 1,000 times the lethal amount for a human. Additionally, it's known for its giant red spot, which is basically a hurricane-like storm that has been brewing for over 300 years.
Jupiter, like the sun, is composed of hydrogen and helium. Because of this, scientists believed that Jupiter formed early in our solar system's history. However, how Jupiter formed remains a mystery — perhaps a mystery that Juno will solve?
Here on Earth, we'll also be able to get an great glimpse at Jupiter, without the help of Juno. On April 8th, Jupiter was the closest its been to Earth in more than a year. The planet was only 414 miles away from Earth (so close, right?!) and is now in "opposition" which means that the Earth is now directly in between the Sun and Jupiter.