More impressive images had to wait until the Voyager 1 and 2 probes, both of which left Earth in 1977 and reached Jupiter in 1979, to take amazing observational data of the giant planet. The Pioneer 10 and 11 spacecraft, launched in March 1972 and April 1973, respectively, studied the asteroid belt and swept past Jupiter, gathering information about its intense radiation belts and snapping a few early photos, according to Live Science's sister site.

In modern times, humans have launched many probes that have flown past or orbited the gas giant. One of the first people to make detailed observations of Jupiter was Italian astronomer Galileo Galilei, who gazed at the planet through his telescope in 1610, seeing its four largest moons, according to according to NASA. Its central axis is tilted only 3 degrees, unlike Earth's axial tilt of 23 degrees, meaning that Jupiter doesn't experience much seasonal variation throughout its year. The planet has the shortest day in the solar system, lasting a breezy 9.93 hours. A year on Jupiter lasts 11.86 Earth years. Jupiter orbits at an average distance of 484 million miles (778 million km) from the sun, according to NASA. The planet might have a central core of solid material or a thick, dense 'soup,' made mainly of iron and silicon, that could be up to about 90,000 degrees Fahrenheit (50,000 degrees Celsius). Somewhere around halfway to the gas giant's center, internal pressures become so great that electrons are squeezed off their parent hydrogen atoms, creating a superconductive metal that is thought to drive Jupiter's enormous magnetic field, according to the agency. Deeper in the atmosphere, increasing pressures and temperatures compress hydrogen gas into a liquid, meaning Jupiter has the largest ocean in the solar system, one made of hydrogen instead of water, according to NASA. Near Jupiter's south pole, astronomers have found a dramatic hexagonal storm about the size of Texas surrounded by six other swirling maelstroms.ĭata from Juno have shown that Jupiter's jet streams may reach depths of about 2,000 miles (roughly 3,200 km), according to NASA. The Great Red Spot has been seen eating other, smaller storms, and scientists think that when certain cyclones slam into the spot, they increase its speed and, potentially, its lifetime. (Image credit: Enhanced Image by Gerald Eichstadt and Sean Doran (CC BY-NC-SA) based on images provided courtesy of NASA/JPL-Caltech/SwRI/MS) The color-enhanced image is a combination of three separate images taken on April 1, 2018. This image of Jupiter's iconic Great Red Spot and surrounding turbulent zones was captured by NASA's Juno spacecraft as it performed its 12th close flyby of Jupiter.

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