Skywatchers on Thursday evening, Feb. 6, will notice an eye-catching pairing-off between two of the brightest objects in the ...

There are currently 92 moons known to orbit Jupiter. The four largest – Io, Europa, Ganymede and Callisto – were discovered by Galileo Galilei in 1610 when he pointed the first astronomical telescope ...

They are more commonly referred to as the Galilean moons of Jupiter owing to the fact that they were discovered by Galileo. The four Galilean moons – Io, Europa, Ganymede and Callisto – are ...

Loki Patera is 202 kilometres (126 mi) in diameter, covers 20,000 sq km (7,700 sq mi), and was the largest volcanic feature found on Io until these new observations revealed the hot spot in the south ...

The end of February is the beginning of an evening appearance by the as yet unmentioned planet, Mercury. It appears by about ...

Galileo’s repeated observations over several nights and realized they were moons orbiting the gas giant. And thus, Io, Europa and Ganymede became known as the Galilean moons of Jupiter.