The planetary core consists of the innermost layer(s) of a planet. Image File history File links Download high resolution version (3373x900, 690 KB) The internal structure of the inner planets. ... Image File history File links Download high resolution version (3373x900, 690 KB) The internal structure of the inner planets. ... The eight planets and three dwarf planets of the Solar System. ...

The cores of terrestrial planets tend to be mainly composed of iron and can include a solid and/or a liquid layer. Earth's core is partially liquid, whilst the cores of Mars and Venus are thought to be completely solid, due to their lack of an internally generated magnetic field.^[1] In our solar system, core size can range from about 20% (the Moon) to 75% of a planet's radius (Mercury). The inner planets, Mercury, Venus, Earth, and Mars, their sizes to scale. ... Earth, also known as the Earth or Terra, is the third planet outward from the Sun. ... Mars is the fourth planet from the Sun in the solar system, named after the Roman god of war (the counterpart of the Greek Ares), on account of its blood red color as viewed in the night sky. ... (*min temperature refers to cloud tops only) Atmospheric characteristics Atmospheric pressure 9. ... Magnetic field lines shown by iron filings In physics, a magnetic field is a solenoidal vector field in the space surrounding moving electric charges and magnetic dipoles, such as those in electric currents and magnets. ... Apparent magnitude: up to -12. ... This article is about the planet. ...

Comparison of the inner core of the extrasolar planet HD 149026b and Jupiter

Gas giants also have iron-rich cores. Although these cores are proportionately much smaller than those of terrestrial planets, gas giants are so large that their cores can actually be larger than Earth. Jupiter's core is thought to be approximately 12 times the mass of Earth (3% of its total mass), and the exoplanet HD 149026 b is thought to have a core approximately 70 times the mass of Earth. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... This article does not cite any references or sources. ... Adjectives: Jovian Atmosphere [4] Surface pressure: 20–200 kPa[8] (cloud layer) Scale height: 27 km Composition: Jupiter (IPA: or ) is the fifth planet from the Sun and the largest planet within the solar system. ... Infrared Image of a possible extrasolar planet (lower left) in the Constellation Taurus, taken by the Hubble Space Telescope. ... HD 149026 b, is a transiting extrasolar planet orbiting the star HD 149026. ...

It is thought that some gas giants orbiting very close to their primaries may have their atmospheres stripped away, leaving only their core behind. This as-yet hypothetical class of planets are called "Chthonian." A Chthonian planet (sometimes misspelled Cthonian), is a gas giant with its hydrogen and helium atmosphere stripped away due to its closeness to its star. ...

Some moons, asteroids and other minor planets may also have well-differentiated cores depending on their size and history. Jupiter's moons Io and Europa are in many ways sisters of the terrestrial planets and have very substantial cores comprising about a third of their radii. The large asteroid 4 Vesta is likewise believed to have a differentiated structure with a distinct core. A natural satellite is an object that orbits a planet or other body larger than itself and which is not man-made. ... 253 Mathilde, a C-type asteroid. ... Minor planets, or asteroids or planetoids, are minor celestial bodies of the Solar system orbiting the Sun (mostly Small solar system bodies) that are smaller than major planets, but larger than meteoroids (commonly defined as being 10 meters across or less[1]), and that are not comets. ... Atmosphere Surface pressure: trace Composition: 90% sulfur dioxide Io (eye-oe, IPA: , Greek Ῑώ) is the innermost of the four Galilean moons of Jupiter and, with a diameter of 3,642 kilometers, is the fourth largest moon in the Solar System. ... Apparent magnitude: 5. ... 4 Vesta (ves-ta) is the second most massive asteroid in the asteroid belt, with a mean diameter of about 530 km and an estimated mass 12% the mass of the entire asteroid belt. ...

References

1. ^ Luhmann, J. G.; Russell, C. T. (1997). "Mars: Magnetic Field and Magnetosphere". Encyclopedia of Planetary Sciences: 454-6.