Jupiter

Jupiter is the fifth planet from the Sun and the largest in the Solar System.

Distance from Sun: 778.5 million km

Orbital period: 12 years

Radius: 69,911 km

Mass: 1.898 × 10^27 kg (317.8 M⊕)

Four major moons

Io

Europa

Ganymede

Callisto

I would highly recommend to look at jupiter through a telescope as even a small telescope you will be able to see these moons orbiting Jupiter.

Jupiter currently has 79 known satellites.

Flyby missions

1973 Pioneer 10

1974 Pioneer 11

1979 Voyager 1 and Voyager 2

1992 Ulysses (and again in 2004)

2000 Cassini

2007 New Horizons

Orbital missions to Jupiter

Juno (arrival 4 July 2016)