Jupiter

Jupiter is the 5th planet from the Sun. It is the largest planet in the Solar System. Jupiter is a gas giant and it's mass is about 2.5 times that of the mass of all of the other planets in the Solar System combined. Jupiter has slightly less than 1/1000 the mass of the Sun. Jupiter is the 3rd brightest object visible from the Earth's night sky after the Moon and Venus. People have been observing Jupiter since prehistoric times. Jupiter is named after the Roman god with the same name. This was deemed fitting as Jupiter was the king of the gods and Jupiter the planet is supreme in size amongst the other planets in the Solar System. 

Jupiter is primarily composed of hydrogen. Helium constitutes 1/4 of its mass and 1/10 of its volume.  It is likely, that at Jupiter's center, can be found a rocky core of heavier elements. However, Jupiter, like other gas giants, lacks a well-defined solid surface. Due to Jupiter's rapid rotation, its shape is an oblate spheroid. There is a slight, but noticeable bulge around the equator. 

Great Red Spot

The 'Great Red Spot' is a high pressure region of Jupiter's atmosphere. This region is meteorologically classified as an 'anticyclonic storm,' a storm with a high pressure center. It is located 22 degrees south of Jupiter's equator. It produces wind speeds of up to 268 miles per hour. 

It has been suspected that this storm existed since at least the 17th century when it was observed with telescopic measurements. 

Pioneer 10, was the first spacecraft to go to Jupiter. It was launched in 1972 by NASA. It made its close approach with the planet in December of 1973.