Europa: A little moon with a chance of life At last count, Jupiter has 95 moons, but the four main ones — Ganymede, Callisto, Io and Europa — were discovered in 1610 by famed Italian ...

July 25 has been a date marked by remarkable events that have shaped history.One of the most profound events occurred on July ...

Look east around 4 a.m. local time, just before dawn, to see the slender form of the crescent moon climb above the horizon.

A telescope with an aperture of 6 inches or more will allow viewers to observe Jupiter's four brightest moons, Io, Europa, Ganymede and Callisto, as well as the planet's gargantuan banded cloud ...

ESA's Mars Express orbiter captured footage of the Mars' moon Deimos pass in front of Ganymede, Europa, Jupiter, Io and Callisto (in that order).

Even with a small telescope or binoculars, you can see the four largest moons of Jupiter: Io, Europa, Ganymede and Callisto.

Jupiter’s four largest moons – Io, Europa, Ganymede and Callisto – were the first ever discovered orbiting another planet. They were spotted by Galileo Galilei more than 400 years ago, in 1610.

Since completing its primary science objectives in orbit of Jupiter, Juno has been conducting flybys of the Jovian moons Io, Europa, Ganymede, and Callisto.

Good binoculars may make it possible to see the planet’s four biggest moons — Io, Europa, Ganymede, Callisto. It reached opposition, its closest point to Earth, on Dec. 7 and appears as large ...

Credit: Astronomy: Roen Kelly Io, Europa, Ganymede, and Callisto orbit every two to 17 days. The innermost three moons are locked in a 1:2:4 resonance, so their relative positions repeat.

Io, Europa, Ganymede and Callisto are, like Earth’s Moon, relatively large, spherical complex worlds. Two previous NASA missions have sent spacecraft to orbit the Jupiter system and collected ...