Neptune, Voyager 2 image
Neptune. Neptune is a gas giant, composed mostly of hydrogen and helium with some methane. Seen at centre is the Great Dark Spot, thought to be a hole in the methane cloud deck of Neptune, accompanied by bright, white, high-altitude clouds. This image was reconstructed from two images (one through a green filter and one through an orange filter), taken by the narrow-angle camera aboard the Voyager 2 spacecraft in August 1989.
© JPL/NASA/SCIENCE PHOTO LIBRARY
Earth and Moon with dwarf planets
Earth and Moon with dwarf planets. Scaled computer artwork of (from left) Earth, the Moon, Pluto and Ceres. The latter are two of the solar system's dwarf planets. Pluto, which used to be a planet, was demoted in August 2006 to the status of dwarf planet, reducing the solar system's number of planets to eight. The definition of a dwarf planet is an object large enough to be spherical due to gravity, and with an independent orbit. A true planet, such as the Earth, has to dominate its orbit around the Sun. Pluto fails because it is one of many Kuiper Belt objects in the outer solar system. Ceres fails because it is one of many objects in the asteroid belt. The Moon fails because it is a satellite of the Earth.
© DETLEV VAN RAVENSWAAY/SCIENCE PHOTO LIBRARY
Abbey Park, Cirencester, August 1924
A GWR Publicity view of the Norman Arch in Abbey Grounds Park, Cirencester, Gloucestershire in August 1924. The walls of the 12th century arch are covered in ivy and two boys are turned towards the camera. The Norman Arch is the oldest building in Cirencester and is the last remaining structure of Cirencester Abbey.
© STEAM Museum of the GWR