Planets Gallery

Solar System, artwork

Solar System. Artwork of Earth's solar system, showing the planets and other objects that orbit the Sun (upper right). The separations of the orbits are not shown to scale. Most of the mass of the solar system is found in the Sun. The planets, from inner to outer, are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Also shown here (beyond Neptune) is Pluto, a former planet now considered a large dwarf planet in the Kuiper Belt. The asteroid belt is shown between Mars and Jupiter. At upper left is a meteor shower, shown as it would appear from the Earth's surface as the meteors impact the atmosphere

© CLAUS LUNAU/SCIENCE PHOTO LIBRARY

Solar system map from 1853

Historical map of the solar system, published in Germany in 1853. The main diagram shows the orbits of the first seven planets out to Uranus. Neptune had been discovered in 1846, but is only shown on the list at upper left. Pluto was not discovered until 1930. The phases of the Moon are illustrated at lower left. Details of Saturn's rings are shown at upper right, while conjunctions of Mercury and Venus are shown at lower right. The main diagram, drawn to scale, shows how the inner solar system is tiny when compared to the vast distances of the outer solar system. The highly elliptical orbits of comets are shown, as well as the asteroid belt

© DETLEV VAN RAVENSWAAY/SCIENCE PHOTO LIBRARY

Planets internal structures

Planets internal structures, and Pluto, computer artwork. Mercury, Mars and Venus consist of a large iron core (spherical), surrounded by a thick silicate mantle (yellow) covered in a surface crust. Earth consists of an inner core of solid iron and nickel (yellow) and a molten outer core (orange), surrounded by a mantle of highly viscous liquid (brown) covered by a surface crust. Jupiter and Saturn consist of a core of rock (spherical) surrounded by ice (mat grey). This is surrounded by a layer of liquid metallic hydrogen (grey) and liquid normal hydrogen (blue). Uranus and Neptune have a core of rock (spherical) surrounded by ice and liquid hydrogen (blue). Pluto has a dense rocky core (grey) surrounded by ice (black)

© CHRISTIAN DARKIN/SCIENCE PHOTO LIBRARY