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Jupiter was Formed Approximately 4.5 Billion Years Ago

Jupiter was formed approximately 4.5 billion years ago from dust and debris cast off from a large rotating disk of dust and gases that surrounded the Sun. Named for the king of the gods in Roman mythology, Jupiter is the fifth planet from the Sun and the largest planet in the solar system. Jupiter facts tell us that Jupiter is known for its many moons, the faint ring system that surrounds the planet, and the colorful bands of clouds visible in its upper atmosphere. Jupiter is composed almost entirely of hydrogen and helium and is one of four “Gas Giants” in the solar system.

Jupiter was First Observed by the Babylonians in 700 BC

Because Jupiter is easily seen in the night sky, it has been known for centuries to people from Earth’s earliest civilizations. The ancient Babylonians were among the first to record its existence in texts dating as far back as 700 BC. Scientific observation of Jupiter began in 1609, when Galileo Galilei became the first astronomer to view Jupiter by telescope. He is credited with the discovery of Jupiter’s four largest moons in 1610, when he observed that objects he had previously identified as small fixed stars were changing positions in the sky, leading him to conclude they were actually moons orbiting the planet. His discovery proved to be of monumental importance to science, leading to the eventual rejection of earlier theories that had placed Earth at the center of the universe.

Jupiter’s Gaseous Surface Makes it Impossible to Land a Spacecraft on the Planet

Jupiter is composed primarily of gas – 90% hydrogen and 9.999% helium – which means it doesn’t have a solid surface on which you could stand or land a spacecraft. For scientific purposes, researchers have defined the surface of Jupiter as the point where the pressure of the atmosphere is equal to exactly one bar, which is identical to the atmospheric pressure on the surface of the Earth. Jupiter facts reveal that Jupiter’s undefined surface and the harshness of its atmosphere make it impossible to land a spacecraft there. Any attempt to descend below the defined surface of the planet would be met with crushing pressure, more than 1,000 times that of the atmospheric pressure of Earth!

Jupiter’s Massive Atmosphere is Made up Almost Entirely of Hydrogen

Jupiter’s atmosphere is composed primarily of gases, with trace amounts of ammonia, sulfur, methane and water vapor. Jupiter facts reveal that Jupiter’s atmosphere is divided into four ascending layers that include the troposphere, stratosphere, thermosphere, and exosphere. The troposphere, also known as the surface atmosphere, consists of bands of ammonia clouds that are categorized into belts (darker bands of clouds) and zones (lighter bands of clouds) that often appear as red and white stripes around the outside of the planet. The dots and circles visible within the bands are actually dramatic storms, which can last anywhere from several days to several years, and produce weather conditions that include lightning, high winds, hurricanes, and tornadoes. Jupiter’s thermosphere is characterized by the stunning bands of rippling blue light, known as the aurora, that appear around the planet’s poles.

Jupiter is the Largest Planet in the Solar System

Jupiter facts reveal that Jupiter is by far the largest planet in the solar system; so large in fact, that all the other planets could fit within it. Jupiter’s mass is measured at 1,898,130,000,000,000,000,000,000,000 kg, more than 317 times that of the Earth’s mass. The gas giant has a diameter of 88,846 miles (142,984 km) and land surface area of 23,713,907,537 square miles (61,418,738,570.44 square kilometers), more than 120 times that of the surface area of Earth. Although significantly larger, Jupiter’s density is equal to only a fifth of the density of Earth, and is comparable to the density of water.

Jupiter’s Core is Hotter than the Surface of the Sun

Temperatures on Jupiter range from extremely hot to extremely cold and vary according to the depth and pressure of the atmosphere. Jupiter facts reveal that temperatures in Jupiter’s upper atmosphere average a frigid -234°F (-145°C). Descending farther into the interior, temperatures begin to rise, progressing from a balmy 70°F (21°C) at just below the clouds to a scorching 43,000°F (24,000°C) at the planet’s core. The extreme disparities in temperature are believed to be behind Jupiter’s intense storms, which are formed when the forces of warm and cold air collide, just as they are here on Earth.

Jupiter has More Moons than Any Planet in the Solar System

According to NASA, Jupiter has 50 confirmed moons and 17 unconfirmed moons. Jupiter facts tell us that most of the planet’s moons were captured by the powerful magnetic field of the planet. Jupiter’s four largest moons, known as lo, Europa, Ganymede, and Callisto, were discovered by Galileo Galilei in 1610. Ganymede is Jupiter’s largest moon and the largest in the solar system. Composed of ice and rock, Ganymede is the only moon known to have its own magnetic field. Scientists are convinced a large saltwater ocean exists some 124 miles beneath the surface of Ganymede. It is estimated to be ten times deeper than the oceans on Earth and is buried beneath a thick layer of ice almost 100 miles deep.

Jupiter’s Ring System Consists of a Main Ring, the Halo Ring, and Two Gossamer Rings

Jupiter’s ring system was discovered by NASA’s Voyager 1 spacecraft in 1979. Jupiter facts tell us that the rings are composed primarily of small dust particles that are very faint and not easily seen, even with the aid of a telescope. Scientists believe the rings were formed from dust created from the collision of meteorites with two of Jupiter’s closest moons. Jupiter’s main ring is approximately 6,400 km wide and less than 30 km thick. It orbits approximately 122,800 km out from the center of the planet and is bordered by the Halo ring to the near side of Jupiter and the Gossamer ring to the far side. The Gossamer ring actually consists of two separate rings, one embedded within the other. Known as the Amalthea Gossamer Ring and Thebe Gossamer Ring, they are named for the two small moons that scientists believe were involved in the formation of Jupiter’s rings.

Jupiter is the Fourth Brightest Planet in the Solar System

Jupiter is the fourth brightest planet in the solar system, behind the Sun, Moon, and Venus. Jupiter facts tell us that it is brighter than Sirius, the solar system’s brightest star, and can be seen from earth with varying degrees of clarity according to its position in the sky and distance from the Earth. Every 13 months, Jupiter enters into a period known as “opposition,” the point at which it is positioned directly opposite the Sun, causing it to shine brighter than any other time of the year. During opposition, Jupiter will appear as a bright, cream-colored disk, surrounded by small pinpricks of white light that will be one or more of its four largest moons.

Jupiter has the Shortest Day of any Planet in the Solar System

Jupiter facts show that Jupiter spins faster on its axis than any other planet in the solar system, completing a rotation in just under 10 hours, giving it the shortest day of any planet in the solar system. By contrast, it takes Jupiter approximately 4,330 days to complete an orbit around the Sun, making a year on Jupiter equivalent to nearly 12 years here on Earth. Factors affecting the length of Jupiter’s year include its average distance from the Sun, calculated at approximately 483,682,810 Miles (778,412,020 KM), and the speed at which it travels around the sun, estimated at approximately 29,236 miles per hour (47,051 kilometers per hour).

Jupiter is Home to a Massive Hurricane that has been Raging for More than 350 Years

One of Jupiter’s most distinctive features is the giant red spot visible in the planet’s Southern Hemisphere. Believed to be an enormous hurricane, three times larger than the Earth, the slightly oval, reddish-colored spot has been observed for more than 350 years at its location near Jupiter’s equator. Jupiter facts reveal that it was first identified by Italian astronomer Giovanni Domenico Cassini in 1665 and has been studied continuously since 1878, when American astronomer Carr Walter Pritchett observed it through a 12-inch refractor telescope at the Pritchett Institute. Scientists believe the storm is powered by condensation of water and ammonia in the lower levels of Jupiter’s atmosphere.

Jupiter’s Magnetic Field is More Than 20,000 Times Stronger than Earth’s

Jupiter has the largest and strongest magnetic field of any planet in the solar system. It is more than 20,000 times stronger than the Earth’s magnetic field and stretches as far as 4.3 million miles (7 million kilometers) toward the sun. Jupiter facts tell us that this intense magnetic field is created through electrical currents generated from within the planet’s rapidly spinning core of liquid metal hydrogen. Jupiter’s magnetic field is so strong that electrically charged particles trapped inside it have been known to damage the instruments of spacecraft operating within the vicinity of the planet.

Jupiter’s Powerful Storms can Last for Years at a Time

Jupiter is one of the stormiest planets in the solar system. Jupiter facts reveal that the planet’s unstable atmosphere is capable of producing winds up to 400-mph and lightning 100 times as bright as the lightning we experience on Earth. The planet is known for brewing huge storms that can grow to cover thousands of miles in just a few hours, posing a very real hazard for spacecraft traveling within its vicinity. Seasons on Jupiter are defined in terms of vernal equinox, summer solstice, autumnal equinox, and winter solstice, with each season lasting the equivalent of approximately three Earth years. The weather on Jupiter experiences little change from one season to the next, due to the ever so slight tilt of its axis toward the Sun.

Deep within Jupiter’s Interior is a 25,000-Mile Deep Ocean of Liquid Metallic Hydrogen

Below Jupiter’s thick outer atmosphere of hydrogen gas and the layer of liquid hydrogen that lies beneath it, is an ocean of liquid metallic hydrogen 25,000 miles deep. Scientists believe that increased atmospheric pressure that occurs upon descent into the interior of the planet causes changes to the state of the hydrogen that makes up the bulk of the planet’s composition. According to researchers, the combination of Jupiter’s liquid metallic hydrogen ocean and the rapid rotation of the planet are the reason for Jupiter’s immense magnetic field that is the largest in the solar system, at 450 million miles long.

Jupiter’s Intense Gravity Protects Earth from Devastating Collisions with Comets

Jupiter facts tell us that Jupiter’s intense gravitational field provides the Earth with invaluable protection from wayward comets, asteroids, and meteorites that tend to zip about the solar system in uncontrolled fashion. Dangers posed to Earth by NSOs (near space objects) range from locally life threatening events to annihilation of Earth and its inhabitants. Catastrophic phenomena that could occur from such collisions include tsunamis, flash fires, earthquakes, shockwaves, and atmospheric darkening. Scientists at NASA’s Jet Propulsion Laboratory in Pasadena, California are tracking the progress of known NSOs in the solar system in an effort to learn more about them and hopefully discover a remedy for any rogue space objects that may target Earth in the future.

Jupiter’s Collision with Shoemaker-Levy 9 Comet was Recorded by Hubble Space Telescope

When the Shoemaker-Levy 9 comet broke apart and slammed into Jupiter in July of 1994, the historic event was witnessed and recorded by the Hubble Space Telescope, a powerful telescope launched into orbit of Earth in 1990. The previously unknown comet was discovered in March of 1993 by Eugene and Carolyn Shoemaker and David Levy, astronomers at the Palomar Observatory in California, who noticed that the comet had been “captured” by Jupiter’s intense gravity during a close pass to the planet. Through calculations of the comet’s projected path, they were able to forecast the relative date and location of its predicted crash into Jupiter. Scientific reports indicate that the first fragment hit Jupiter at a speed of 60 kilometers per second, resulting in a force of impact equivalent to the energy of more than a million one-megaton nuclear bombs, and leaving behind a scar on Jupiter’s surface that was larger than the Earth itself.

Scientists Believe Jupiter’s Moon Europa Holds Best Chance for Life in the Solar System

Scientists believe Jupiter’s moon Europa may be the most likely place other than Earth for life in the solar system. Jupiter facts reveal that Europa is one of four moons discovered by Galileo Galilei in 1610. Europa’s surface is covered by a thick sheet of ice, under which scientists believe exists a saltwater ocean that may harbor some form of life. Researchers believe that if life does exist on Europa, it probably lives within or under rocks at the bottom of the ocean, where internal heat sources would provide enough warmth to heat the rocks and keep the water from freezing.

Jupiter’s Colors are Affected by Storms and Winds in the Atmosphere

Images of Jupiter often show the planet in subtly changing shades of red, orange, brown, yellow, and white. Jupiter facts tell us that the planet’s colors are created from the reflection of sunlight on chemicals present in its atmosphere. The white, brown, and red streaks visible on Jupiter’s surface are a result of chemical reactions to sulfur drawn into the clouds from the planet’s core by powerful storms that buffet its atmosphere, while the blue and white hues are created by patches of ammonia ice and water ice that are present in the clouds of Jupiter’s upper atmosphere.

Jupiter’s Intense Gravity Allows Spacecraft to Reach the Outer Regions of the Solar System

Scientists are using a technique known as “gravity assist” to boost spacecraft into previously unreachable regions of the solar system. First employed in 1962, gravity assist uses the gravity and motion of a planet to transfer kinetic energy to the orbiting spacecraft, thereby increasing its velocity and hurtling it out into space at a much greater speed than it had upon entering the planet’s field of gravity. Voyager 1 successfully employed this technique in 1979, gaining a relative speed of approximately 35,000 mph as it left the atmosphere of Jupiter on its way to Saturn!

NASA’s Spacecraft Juno is Scheduled to Reach Jupiter in 2016

NASA has conducted eight missions to Jupiter, beginning with a flyby by Pioneer 10 in 1973 and most recently by New Horizons, which took pictures of Jupiter and its moons on its way to the planet Pluto in 2007. Galileo was the first spacecraft to orbit Jupiter. Launched in 1989, Galileo arrived at Jupiter in December of 1995, dropping a probe into the depths of its atmosphere that would provide valuable information on the temperature, pressure, density, and atmospheric composition of the planet. NASA’s most recent mission to Jupiter is the spacecraft Juno. Launched in August of 2011, Juno is expected to reach Jupiter in July of 2016, when it will begin a journey that is projected to last approximately one year as it orbits the planet a projected 32 times.

Jupiter Facts – Facts about Jupiter Summary

Jupiter FactsJupiter is the largest planet in the solar system and the fifth planet from the Sun. Composed primarily of hydrogen and helium, Jupiter was formed more than 4.5 billion years ago from dust and debris cast off from a huge rotating disk that surrounded the sun. Jupiter has 67 known moons, four of which were discovered by Galileo Galilei in 1610, and a ring system discovered in 1979 by NASA’s Voyager 1 spacecraft. Jupiter is home to the solar system’s largest and longest lasting storm. Known as the “Great Red Spot,” the immense hurricane-like storm has been raging in Jupiter’s atmosphere for more than 350 years.