25-May-2017: Juno Spacecraft Reveals Spectacular Cyclones At Jupiter's Poles

NASA's Juno spacecraft has spotted giant cyclones swirling at Jupiter's north and south poles.

Juno arrived at Jupiter last summer. It's the first spacecraft to get a close-up look at the planet's poles. It's in an orbit that takes it skimming close to the cloud tops of the gas giant once every 53 days. After each close pass, the spacecraft sends a trove of data back to Earth.

Scientists weren't expecting to see cyclones at the poles. Ultimately, scientists will want to understand how these cyclones change over time and whether they form differently in the north and south poles.

There's some startling new data about the spectacular auroras at the poles of Jupiter — which are like the Northern Lights on Earth but much more dazzling. These auroras are caused by energetic particles streaming along Jupiter's magnetic field lines, and there should be strong electrical currents associated with all those streaming particles.

Juno also revealed that Jupiter’s magnetic field is 10 times stronger than the strongest magnetic field on Earth and twice as strong as anticipated, exceeding researchers’ expectations.

Also, the early data are suggesting the presence of a core in Jupiter, which was always considered to be a gas giant. More data should help provide a more precise understanding than fuzzy.

Another surprise from Juno is the concentration of ammonia in Jupiter's atmosphere. Scientists thought ammonia was most likely distributed evenly throughout the atmosphere. The data show there's more ammonia near the equator than there is at other latitudes.

Juno is expected to make about two dozen more close passes over Jupiter's poles, so there'll likely be more puzzles to come.

3-Feb-2017: Juno Spacecraft Makes Its Fourth Flyby Over Jupiter

NASA’s Juno spacecraft made its fourth flyby over Jupiter’s mysterious cloud tops.

At the time of closest approach, Juno will be about 2,670 miles (4,300 kilometers) above the planet’s cloud tops and traveling at a speed of about 129,000 mph (57.8 kilometers per second) relative to the gas giant. All of Juno’s eight science instruments, including the Jovian Infrared Auroral Mapper (JIRAM) instrument, will be on and collecting data during the flyby.

The Juno science team continues to analyze returns from previous flybys. Revelations include that Jupiter’s magnetic fields and aurora are bigger and more powerful than originally thought and that the belts and zones that give the gas giant’s cloud top its distinctive look extend deep into the planet’s interior. Peer-reviewed papers with more in-depth science results from Juno’s first three flybys are expected to be published within the next few months. Also, JunoCam, the first interplanetary outreach camera, is now being guided with the assistance from the public — people can participate by voting for what features on Jupiter should be imaged during each flyby.

Juno is currently in a 53-day orbit period around Jupiter as the team evaluates options for performing a maneuver to get the spacecraft into a shorter orbit period. While the initial plan was for the mission was to have 14-day orbits during this time, Juno can reveal amazing details about Jupiter even if it stays in the longer orbits for the duration of the mission.

Juno was launched in 2011 on a mission to study Jupiter’s composition and evolution. It’s the first spacecraft to orbit Jupiter since Galileo. Juno spacecraft successfully entered Jupiter’s orbit recently, after a five year journey. Juno launched on August 5, 2011, from Cape Canaveral, Florida, and arrived at Jupiter on July 4, 2016. During its mission of exploration, Juno soars low over the planet’s cloud tops — as close as about 2,600 miles (4,100 kilometers). During these flybys, Juno is probing beneath the obscuring cloud cover of Jupiter and studying its auroras to learn more about the planet’s origins, structure, atmosphere and magnetosphere.

The primary goals of the $1.1 billion mission are to find out whether Jupiter has a solid core, and whether there is water in the planet’s atmosphere — something that may not only provide vital clues to how the planet formed and evolved, but also to how the solar system we live in came into existence. At the end of its mission, Juno will dive into Jupiter’s atmosphere and burn up — a “deorbit” manoeuver that is necessary to ensure that it does not crash into and contaminate the Jovian moons Europa, Ganymede and Calisto.

The Juno spacecraft – named after the Roman goddess and wife of Jupiter – is packed with nine instruments capable of peering into the planet’s heart. It will fly 2,600 miles above the cloud tops – 3,000 miles closer to the surface than any other mission has ever achieved. Juno became the first spacecraft to cruise this far out into the solar system powered solely by the sun, beating Europe’s Rosetta spacecraft. A trio of massive solar wings sticks out from Juno like blades from a windmill, generating 500 watts of power to run its nine instruments. Juno, built by Lockheed Martin, is an armored spacecraft – its computer and electronics are locked in a titanium vault to shield them from harmful radiation. Even so, Juno is expected to get blasted with radiation equal to more than 100 million dental X-rays during the mission.