Nasa Gallery

Blue Marble image of Earth (2005)

Blue Marble image of Earth. Composite satellite image of Earth's western hemisphere, centred on the Atlantic Ocean. North is at top. The image is one of a set entitled Blue Marble: Next Generation, released in October 2005, which improves upon Blue Marble 2000. The new images combine data collected over a longer period of time at an improved resolution of 500 metres per pixel. Features include cloud cover, oceans, phytoplankton activity, topography, and city lights in the nighttime part of the hemisphere. Data was obtained mainly by NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra and Aqua satellites between July 2001 and July 2004. Topography is based on radar data collected by the Space Shuttle Endeavor

© Nasa Earth Observatory/Science Photo Library

Aurora over Antarctica, satellite image

Aurora over Antarctica, ultraviolet satellite image. Australia is at upper left. This is the aurora australis (green ring), the southern lights display. It is caused by interactions between charged particles from the Sun (the solar wind) and gas atoms and molecules about 100 kilometres above the Earth. On reaching Earth, the charged particles are drawn by Earth's magnetic field to the poles, where they collide with gas atoms and molecules, causing them to emit light. This display, on 11 September 2005, was caused by a large solar flare. The aurora image was obtained by NASA's IMAGE satellite, which carried out a five year study of Earth's magnetic field

© NASA/SCIENCE PHOTO LIBRARY

Mars Exploration Rover

Mars Exploration Rover on the surface of Mars, artwork. The first of two identical NASA rovers, Spirit, landed on Mars on 4 January 2004. The second, Opportunity, landed on the other side of the planet on 24 January 2004. The rovers are powered by solar panels (black) and are mobile. Cameras mounted on the white mast give scientists panoramic views of the Martian surface. This enables them to instruct the rovers which rocks to analyse and where to look for water. Tools on board the golf buggy-sized rovers include spectrometers for analysing rock samples, a microscope and an abrasion tool. Each rover has a 90-day mission on the surface of Mars

© NASA/SCIENCE PHOTO LIBRARY