Earth, but not as you know it
The European Space Agency (ESA) is Europe’s gateway to space. Its mission: to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe – and the world.
The organisation works closely with space organisations outside Europe, notably Nasa, and has achieved many important breakthroughs since its beginnings in the late 1950s, when two prominent members of the Western European scientific community, Pierre Auger and Edoardo Amaldi, recommended that European governments set up a “purely scientific” joint organisation for space research, taking CERN as a model. In 2005, for example, ESA’s Huygens probe landed on the surface of Titan, Saturn’s largest moon – the first-ever spacecraft to land on a world in the outer Solar System. Over the years, the agency has captured many thousands of images that help scientists analyse everything from changing weather patterns to melting ice, from wildfires and desert storms to phytoplankton blooms of rare beauty.
In these pages, we showcase a small sample of the spectacular Earth images captured by ESA and its partners.
Korea’s Kompsat-2 satellite captured this image over the sand seas of the Namib Desert. The blue and white area is the dry river bed of the Tsauchab. Black dots of vegetation are concentrated close to the river’s main route, while salt deposits appear bright white. Running through the river valley, a road connects Sossusvlei to the Sesriem settlement. At the road’s 45-km point, seen at the lower-central part of the image, a white path shoots off and ends at a circular parking area at the base of a dune. This is Dune 45, a popular tourist stop on the way to and from Sossusvlei.
The image shows the extraordinary landscape of the Tanezrouft Basin, one of the most desolate parts of the Sahara desert, in south-central Algeria. The region is known as “land of terror” because of its lack of water and vegetation. The region is characterised by dark sandstone hills, steep canyon walls, salt flats (white), stone plateaus, sandstone outcrop patterns of concentric loops, and sprawling seas of multi-storey sand dunes known as ergs. Erg Mehedjibat, which appears as a yellow bouquet of flowers (upper right), is made up of a cluster of small star dunes that grow upwards rather than laterally. Japan’s ALOS (Advanced Land Observing Satellite) captured this image with its Advanced Visible and Near Infrared Radiometer type-2 (AVNIR-2) instrument.
New York, New York
A satellite view of the US East Coast, including the city of New York (at upper right). Also visible is Staten Island and the borough of Queens, occupying the southern part of Long Island. Southwest of New York, on the flanks of the Delaware River, is Philadelphia, and further south, past the Delmarva Peninsula of Delaware and Maryland, are the cities of Baltimore and Washington DC. Inland, you can see the valleys and ridges of the Appalachians. This image was acquired by Envisat’s Medium Resolution Imaging Spectrometer (MERIS). Sadly, ESA’s observation satellite, in orbit since 2002, stopped communicating in April this year.
Okavango Delta in northern Botswana
This image is a compilation of three images from Envisat’s radar and shows where the Okavango River empties into the inland Okavango Delta in northern Botswana. The river originates in Angola and ends in northern Botswana, where it has formed a depression in the semiarid Kalahari basin. Appearing purple at the centre of the image is Chief’s Island. In the lower-right portion of the image we can see a large cluster of radar reflections from the town of Maun. At the top of the image, a triangle with similar colouring to the delta can be seen. This is a swamp area and national park located mostly in Namibia.
Electric blue blooms of Ireland
Resembling the brush strokes of French Impressionist Claude Monet, electric blue-coloured plankton blooms swirl in the North Atlantic Ocean off Ireland in this Envisat image. Plankton, the most abundant type of life found in the ocean, are microscopic marine plants that drift on or near the surface of the sea.
While individually microscopic, the chlorophyll they use for photosynthesis collectively tints the surrounding ocean waters, providing a means of detecting these tiny organisms from space with dedicated “ocean colour” sensors such as Envisat’s Medium Resolution Imaging Spectrometer (MERIS), which acquired this image at a resolution of 300 meters.