Neptune Gallery

Voyager 2 image of Neptune

Voyager 2 spacecraft image of the planet Neptune, reconstructed from two images taken through green & clear filters by Voyager's narrow- angle camera. Voyager passed within 5, 000 km of Neptune during August 1989. Towards the north (top of image) is the Great Dark Spot, a giant cloud system that is accompanied by bright, white clouds which undergo rapid changes in appearance. To the south of the Great Dark Spot is a solitary white feature, the so-called "scooter". Further to the south is a smaller dark spot with a bright, white centre. Strong eastward winds cause the smaller, faster moving dark spot to overtake the Great Dark Spot every five days

© Nasa/Science Photo Library

Venus transiting the Sun, telescope image

Gliese 436b is a mid-sized exoplanet roughly the size of Neptune in our own Solar System. It orbits its parent star, the red dwarf Gliese 436, at an extremely close-in distance of just 0.03 astronomical units, taking 2.64 days to go around once. By contrast, Mercury orbits at more than 10 times this distance from the Sun and takes 88 days. Gliese 436b was found using the transit method of discovery, whereby the planet -- as seen from the Earth -- passes first in front of and then behind its parent star. During these events, called transits, the brightness of the system is modulated, enabling astronomers to infer the presence of a planet and calculate its orbital period and mass using the laws of motion

© DAVID NUNUK/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