Jupiter gets Surprisingly Complex New Portrait

Scientists are repainting Jupiter’s portrait — scientifically, anyway. NASA’s Juno spacecraft swooped within 5,000 kilometers (3,100 miles) of Jupiter’s cloud tops last August 27. Scientists’ first close-up of the gas giant has unveiled several unexpected details about the planet’s gravity and powerful magnetic fields. They also give a new view of the planet’s auroras and ammonia-rich weather systems.

Researchers need to revamp their view of Jupiter, these findings suggest. They even challenge ideas about how solar systems form and evolve. The findings come from two papers published May 26 in Science.

“We went in with a preconceived notion of how Jupiter worked,” says Scott Bolton. “And I would say we have to eat some humble pie.” Bolton is a planetary scientist who leads the Juno mission. He works at the Southwest Research Institute in San Antonio, Texas.

Scientists thought that beneath its thick clouds, Jupiter would be uniform and boring. Not anymore. “Jupiter is much more complex deep down than anyone anticipated,” Bolton now observes.

One early surprise came from Jupiter’s gravity. Juno measured that gravity from its tug on the spacecraft. The values suggest that Jupiter doesn’t have a solid, compact core. Instead, the core is probably large and diffuse. It could even be as big as half the planet’s radius, Bolton and his colleagues conclude. “Nobody anticipated that,” Bolton notes.

Imke de Pater is a planetary scientist. She works at the University of California, Berkeley and was not involved in the new studies. The…

Space Photos of the Week: Jupiter, Is That You?!

In this image of Enceladus, one of Saturn’s moons, sunlight along the crescent edge shows its icy ridges and depressions. This photo was taken by the Cassini spacecraft, from 104,000 miles away.

This week the astronomers at NASA spent a lot of time gazing at the two largest planets in our solar system — Jupiter and Saturn. The Juno and Cassini spacecraft are busily sending back information scientists use to learn more about the two planets, resulting in some gorgeous images and even GIFs.

Every 53 days, the Juno spacecraft makes a two-hour…