The vernal equinox occurs as Mercury stands still in Pisces and several of Jupiter’s moons transit in the sky this week.

A total eclipse of the Moon is the highlight of this ... Ganymede and Europa cross the face of Jupiter together March 11/12. At the time shown here, Io has just emerged from eclipse within Jupiter ...

In contrast to Earth's transient auroras, Jupiter's are persistent, fueled primarily by particles from its volcanically active moon, Io. These particles ... a gentle orange color, set against ...

A total eclipse of the Moon is the highlight of this ... between Earth and the giant planet increases. Io, Europa, Ganymede, and Callisto orbit Jupiter with periods ranging from about two to ...

You can also easily view the moon and brighter planets like Mercury ... to discern surface detail as well brighter moons like Jupiter's Io, Europa, Ganymede and Callisto. Deep-sky objects can ...

Jupiter’s magnetic field, however, is constantly bombarded by particles from its close-orbiting moon Io —apart from the solar wind. X-ray flares have been found in Jupiter’s auroras due to ...

Jupiter’s moon Io, the most volcanically active body in the solar system, is littered with hundreds of erupting volcanoes. High-resolution images now reveal several dozen lava lakes, researchers ...

But it hasn’t always been this way. Jupiter’s four largest moons – Io, Europa, Ganymede and Callisto – were the first ever discovered orbiting another planet. They were spotted by Galileo ...

Astronomers have discovered a panoply of new moons orbiting Saturn, bringing the ringed gas giant's total up to 274 moons—far beyond any other planet in our solar system. A natural-color view of ...

But it hasn't always been this way. Jupiter's four largest moons – Io, Europa, Ganymede and Callisto – were the first ever discovered orbiting another planet. They were spotted by Galileo ...