Night Lights in Europe

This animation is made up of two images of Europe at night showing lights from sources in cities and along roads in 1992 and 2010. Bright areas highly correlate with high population density – such as the densely populated cities like London, Paris and Rome. Coastal areas are also more populated than inland regions, making the outline of Europe clearly visible in these night images.

The images were acquired by the United States’ DMSP satellites. The DMSP satellites are run by the National Oceanic and Atmospheric Administration, monitoring the meteorological, oceanographic and solar–terrestrial physics environments for the US Department of Defense. Data from DMSP’s Operational Linescan System can be used to see city lights.

Photo credit: NGDC/DMSP/ESA

Indonesian Islands

This image from the Envisat satellite is dominated by the Indonesian islands of Bali, Lombok and Sumbawa. Bali's central mountains include peaks that reach over 3000 m, including an active volcano visible on the right side of the island. Strong reflections of the radar signal used to produce this image appear like specks of light. They are mainly detectable in the southern part of the island, and are particularly concentrated around the provincial capital city of Denpasar. This is the typical appearance of built-up areas in radar images, owing to the multiple reflection of the radar beam by buildings and especially metal constructions.

This image is a compilation of three passes by Envisat’s radar on 20 June, 19 August and 17 December 2011. Each is assigned a color (red, green and blue) and combined to produce this representation. The colors reveal changes in the surface between Envisat’s passes.

Photo credit: ESA

Earth's Gravilty Field Map, Before and After GRACE

Before the launch of NASA's Gravity Recovery and Climate Experiment (GRACE) in 2002, scientists' knowledge of Earth's gravity field was based upon decades of data from geodetic satellites (left image). GRACE has allowed monthly gravity measurements that are more than 100 times more accurate than these previous models, permitting scientists to characterize how Earth's gravity field varies over time and space, as illustrated by the map on the right, produced after just 13 months of GRACE data.

Image credit: NASA/University of Texas Center for Space Research

Note: For more information, see At 10, GRACE Continues Defying, and Defining, Gravity.

Nunavut Territory, Canada

Nunavut, in northern Canada, is the largest and newest federal territory of the country. The name means "our land" in Inuktitut, given to the territory in 1999. With a population of about 33,000 and an area about the size of Western Europe, Nunavut is the largest and least populous of the provinces in Canada. The land is mostly flat as a result of the actions of the large ice sheet that completely covered the land tens of thousands of years ago. The evidence of this past glaciation is apparent in the thousands of lakes gouged out of the land surface. In the summer the lakes each harbor different biota, and have varying amounts of sediments; hence the great variety of colors seen. The image was acquired July 18, 2001, covers an area of 58 x 59 km, and is located at 67 degrees north latitude, 97.6 degrees west longitude.

Photo credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

The Sikhote–Alin Mountains

The Sikhote–Alin mountain range in Russia’s Far East is pictured in this image, acquired on 27 January 2012 by the MERIS instrument on ESA’s Envisat satellite. In the lower-left portion of the image is the snow-covered Khanka Lake, which spans Russia’s border with northeast China. East of the mainland is the Sea of Japan, which appears to have a feathery cloud-cover. This is due to the cold air coming from the mountains and blowing out to sea. In the upper-right portion of the image is Russia’s largest island, Sakhalin.

Photo credit: ESA

Paris to Portugal

European lights seen by André Kuipers from space. Portugal is to the right of the image, and Paris is the glowing light on the left of the image.

Photo credit: ESA/NASA

Flooding in Algeria

Extremely heavy rains fell at the end of February 2012 in the northern Algerian province of El Tarf, near the Tunisian border. The rainfall total was the greatest recorded in the last 30 years. The Seybouse River overflowed its banks, submerging adjacent villages. Overflow from the Bougous, Mexa and Cheffia dams added to the misery. In this image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft, acquired March 1, 2012, vegetation is shown in red and water is depicted as black to turquoise, depending on how much sediment it contains. The image is located at 36.7 degrees north latitude and 8.3 degrees east longitude. It covers an area of 22 by 37.2 miles (34 by 60 kilometers).

With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry.

Photo credit: NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team

Algerian Sands

This image shows the sandy and rocky terrain of the Sahara desert in western Algeria. With the Mediterranean Sea almost 500 km away, the closest town to the area pictured here is Taghit in the Algerian province of Béchar.

The commercial Ikonos-2 satellite acquired this image on 23 April 2008 at a spatial resolution of 4 m.

Photo credit: EUSI

Italy at Night

This nighttime panorama of much of Europe was photographed by one of the Expedition 30 crew members aboard the International Space Station flying approximately 240 miles above the Tyrrhenian Sea on January 25, 2012. Most of the country of Italy is visible running horizontally across the center of the frame, with the night lights of Rome and Naples being visible to the left and right of center, respectively. Sardinia and Corsica are in the lower left quadrant of the photo. The Adriatic Sea is on the other side of Italy, and beyond it to the east and north can be seen parts of several other European nations.

Photo credit:

West Coast of Africa

The first MERIS observation captured the huge phytoplankton patch produced by the 'upwelling' mechanism along the west coast of Africa near Mauritania. The unprecedented resolution allows fine-scale structures to be detected. In such upwelling areas, northeast trade winds bring deep and nutrient-rich water to the surface, feeding phytoplankton. Changes in climate affect the intensity of the upwelling with important consequences for marine ecosystems, fisheries and local economies.

One important task for MERIS is to provide overviews of the dynamics of upwelling areas and their primary production. This, in turn, could improve management of fish stocks within sustainable limits. Another important task for MERIS is to provide information on carbon fixation through photosynthesis within the global ocean for a better understanding of the carbon cycle.

Instrument: MEdium Resolution Imaging Spectrometer (MERIS)
Date of Acquisition: 22 March 2002
Orbit number: 00306
Instrument features: Full resolution image (300-meter resolution)
MERIS was designed to measure the concentration of phytoplankton. The colors seen by MERIS indicate the concentration of chlorophyll, the pigment that phytoplankton use for photosynthesis. MERIS can detect chlorophyll concentrations as low as 0.01 microgram, or 1/100 000 000 of a gram, per liter. MERIS data will be used to monitor the worldwide distribution of phytoplankton and to compute primary production.

Photo credit: ESA