What is the largest planet in the Solar System?

The planet Jupiter It is the largest in our Solar System, far surpassing the rest of the planets in mass, volume and surface. Its many moons and its constant swirls and gaseous storms, most notably the Great Red Spot, have fascinated astronomers for centuries. Join us in this article to discover some of the most outstanding characteristics of this giant of hydrogen and helium.

The impressive dimensions of Jupiter

Jupiter is the fifth planet farthest from the Sun, standing at a distance of 750 million kilometers. It is a large gaseous mass without a defined surface composed mainly of hydrogen and helium. The total mass is 1.899×1027 Kg, some 318 times greater than the mass of the Earth and 2.48 times greater than the combined mass of the rest of the planets in the Solar System. But it is not the most massive known planet, hundreds of gaseous planets with higher masses have been observed outside the Solar System.

Jupiter's surface has a total area of ​​6.1419×1010 kmtwo and occupies a volume of 1.43128×10fifteen km3about 1321 times the volume of the earth. Nevertheless, the average density of Jupiter is calculated to be 1,326 g/cm3similar to the density of the Sun and approximately 75% less than the average density on Earth.

Only the core would have more mass than the Earth

Jupiter is a gaseous planet composed mainly of hydrogen and helium. The composition varies slightly between the outer and inner layers. Jupiter's atmosphere is the largest in the entire Solar System. and, by mass, is composed of approximately 75% hydrogen, 24% helium, and 1% trace amounts of methane, water vapor, ammonia, and other substances (by volume, 88–92% hydrogen and 8–12% helium) . Is a composition similar to that supposed to have had the solar nebula that gave rise to the Sun itself and the entire Solar System.

In the innermost layers the approximate mass distribution is 71% hydrogen, 24% helium and 5% other elements. Jupiter is believed to have a dense core made up of various elements surrounded by a layer of liquid metallic hydrogen with some helium and is in turn surrounded by a layer of molecular hydrogen. The separation between the atmosphere and the core consists of a transition zone without a clear boundary between the two.

The existence of the dense core was suggested in 1997 due to gravitational measurements of the planet, which indicate that the core must contain 4 to 14% of the total mass of Jupiter, or what is the same, Jupiter's core alone would be 12 to 45 times the mass of Earth.. But the existence of this nucleus is yet to be confirmed.

Jupiter's Many Moons

Jupiter and its satellites (sometimes called "moons") form the so-called jovian system. Until 2017 they have been discovered 69 satellites orbiting Jupiter, although it is likely that there are some more that have not yet been observed. The four largest are called Galilean satellites and they are Io, Europa, Ganymede and Callisto. They were discovered by Galileo Galilei in 1610 and were the first celestial bodies observed to orbit around a body other than the Sun and Earth, which reinforced Copernicus' heliocentric theory.

Io is the most volcanically active body in the entire Solar System, Ganymede is the largest satellite in the Solar System and in Europe, and Callisto is believed to have water in an ocean hidden beneath its surface.

In innermost orbits sits a second group of smaller satellites, the so-called Amalthea Group, which are Metis, Adrasthea, Amalthea, and Thebe. The dust and material expelled by these and other internal satellites feed the ring system of Jupiter.

Exoplanets larger than Jupiter

Jupiter is the largest planet in the Solar System by far from the rest, but not the largest known planet. Outside the Solar System, more than 300 planets larger than Jupiter have been identified. Planets with more mass than Jupiter are known generically as super-Jupiter or super-Jovian, although they do not always have more volume since the greater the mass, the greater the force of gravity on themselves, which tends to reduce the diameter of the planet.

An outstanding example is the planet PSR B1620-26b (Methuselah). This exoplanet was observed in 2003 and was the first identified super jupiter. It is 12.7 billion years old and is the third oldest known planet at the moment.

Gaseous planets larger in volume than Jupiter but less massive, the so-called "bloated planets", have also been observed. Having less mass, the force of gravity is less and the gas can expand more.

Scientists believe that with a mass 13 times the mass of Jupiter, the planet can begin to consume deuterium (²H, an isotope of hydrogen with a neutron in the nucleus) in a nuclear fusion reaction and thus become a brown dwarf. , a body located between a gaseous planet and the smallest star.

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