Jupiter: The Giant Planet
Potential to Support Extraterrestrial Life
|Jupiter: The Giant Planet
Potential to Support Extraterrestrial Life
A look at the solar system's largest planet, Jupiter; its formation and
composition and its mini-solar system of over 60 moons –– some of which
may have the potential to support extraterrestrial life.
Jupiter is the largest planet within our solar system and Jupiter has been called the Solar System's vacuum cleaner, because of its immense gravity and location near the inner Solar System. It receives the most frequent comet impacts of the Solar System's planets.
The Great Red Spot on Jupiter is one of its most familiar features. And it looks like the spot has been around for almost 350 years. It was first identified by Giovanni Cassini, who mentioned it back in 1665.
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with a mass slightly less than one-thousandth of the Sun but is two and a half times the mass of all the other planets in our Solar System combined.
Jupiter is classified as a gas giant along with Saturn, Uranus and Neptune. Together, these four planets are sometimes referred to as the Jovian or outer planets.
The planet was known by astronomers of ancient times and was associated with the mythology and religious beliefs of many cultures. The Romans named the planet after the Roman god Jupiter.
When viewed from Earth, Jupiter can reach an apparent magnitude of −2.94, making it on average the third-brightest object in the night sky after the Moon and Venus. (Mars can briefly match Jupiter's brightness at certain points in its orbit.)
Jupiter is primarily composed of hydrogen with a quarter of its mass being helium; it may also have a rocky core of heavier elements.
Because of its rapid rotation, Jupiter's shape is that of an oblate spheroid (it possesses a slight but noticeable bulge around the equator).
The outer atmosphere is visibly segregated into several bands at different latitudes, resulting in turbulence and storms along their interacting boundaries.
A prominent result is the Great Red Spot, a giant storm that is known to have existed since at least the 17th century when it was first seen by telescope.
Surrounding the planet is a faint planetary ring system and a powerful magnetosphere. There are also at least 64 moons, including the four large moons called the Galilean moons that were first discovered by Galileo Galilei in 1610.
Ganymede, the largest of these moons, has a diameter greater than that of the planet Mercury.
Jupiter has been explored on several occasions by robotic spacecraft, most notably during the early Pioneer and Voyager flyby missions and later by the Galileo orbiter. The most recent probe to visit Jupiter was the Pluto-bound New Horizons spacecraft in late February 2007.
The probe used the gravity from Jupiter to increase its speed. Future targets for exploration in the Jovian system include the possible ice-covered liquid ocean on the moon Europa.
In 1953, the Miller–Urey experiment demonstrated that a combination of lightning and the chemical compounds that existed in the atmosphere of a primordial Earth could form organic compounds (including amino acids) that could serve as the building blocks of life.
Juno Launch - Atlas V
Juno Lifts Off - The Juno spacecraft launched aboard an ULA (United
Launch Alliance) Atlas V rocket from Space Launch Complex 41 at Cape
Canaveral Air Force Station in Florida on Friday, Aug. 5, 2011.
will make a five-year, 400-million-mile voyage to Jupiter, orbit the
planet, investigate its origins and evolution with eight instruments to
probe its internal structure and gravity field, measure water and
ammonia in its atmosphere, map its powerful magnetic field and observe
its intense auroras.
The simulated atmosphere included water, methane, ammonia and molecular hydrogen; all molecules still found in the atmosphere of Jupiter.
The atmosphere of Jupiter has a strong vertical air circulation, which would carry these compounds down into the lower regions.
The higher temperatures within the interior of the atmosphere breaks down these chemicals, which would hinder the formation of Earth-like life. It is considered highly unlikely that there is any Earth-like life on Jupiter, as there is only a small amount of water in the atmosphere and any possible solid surface deep within Jupiter would be under extraordinary pressures.
In 1976, before the Voyager missions, it was hypothesized that ammonia or water-based life could evolve in Jupiter's upper atmosphere. This hypothesis is based on the ecology of terrestrial seas which have simple photosynthetic plankton at the top level, fish at lower levels feeding on these creatures, and marine predators which hunt the fish.
The possible presence of underground oceans on some of Jupiter's moons has led to speculation that the presence of life is more likely there.