Liste europäischer Inseln nach Fläche

Credit Jeff Schmaltz, MODIS Rapid Response Team, NASA/GSFC The island of Sardinia sits between the Mediterranean Sea to the south and west and the Tyrrhenian Sea to the east. To its immediate north is the island of Corsica, which is a part of France. To the east of Sardinia is the middle of the Italian peninsula (not shown). Sardinia glows here with the green blush of spring.

• Vaygach_Island.svg: User:ChongDae
• derivative work: bamse (talk)

Sensor: MSI on Sentinel-2A

Resolution: 20m (Downsampled)

To download the full resolution and other files go to: earthobservatory.nasa.gov/IOTD/view.php?id=77079&src=...

Rhodes (also Rodos) is the biggest island in the Greek Dodecanese chain, which lies in the southeastern Aegean Sea. Rhodes stretches roughly 77 kilometers (48 miles) from northeast to southwest. Its highest point, Mount Attavyros (also Attaviros or Ataviros) reaches 1,200 meters (3,900 feet) above sea level. A variety of vegetation thrives on the rugged island, migratory birds use it as a resting place, and humans have lived here since the Stone Age.

The Thematic Mapper on the Landsat 5 satellite captured this image of Rhodes on August 26, 2011. Green vegetation is fairly abundant over the island, except for Mount Attavyros and some spots along the coast.

Satellite images such as this have provided more than pretty pictures. They have contributed to geologists’ understanding of the island’s history and structure.

Geological research of Rhodes is nothing new; the first geological studies of the island occurred in the 1850s. Geologizing continued the next century, and more systematic research from 1960 to 1965 resulted in a map issued by the Institute of Geology at the University of Milan, Italy. Unfortunately, these studies occurred before the widespread acceptance of a theory that changed our understanding of the Earth: plate tectonics.

Geologists now understand that our planet’s surface is composed of plates that move relative to each other. Rhodes sits in an active area, where the African Plate slides below the Aegean Plate, producing fairly strong earthquakes. Fossils found on the island date back to the late Paleozoic Era before the dinosaurs evolved. The fossils occur in limestone, indicating that what became the island of Rhodes was at that time underwater. Around 15 million years ago, tectonic activity uplifted the whole region, but between 4 million and 3 million years ago, the land sank leaving just the mountaintops above water.

When geologists reexamined Rhodes to create a new map, they not only incorporated advances in geologic theory. They also incorporated advances in remote sensing technology. A paper published in 2007 described the compilation of a new geological map of Rhodes, based in part on satellite observations by Landsat, and by Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite.

NASA Earth Observatory image created by Jesse Allen and Robert Simmon, using Landsat data provided by the United States Geological Survey. Caption by Michon Scott.

Source: NASA World Wind.

To download the full resolution and other files go to: earthobservatory.nasa.gov/IOTD/view.php?id=76883&src=...

Located just 600 miles (970 kilometers) from the North Pole, Franz Josef Land is perpetually coated with ice. Glaciers cover roughly 85 percent of the archipelago’s land masses, and sea ice floats in the channels between islands even in the summertime.

The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite observed the islands of central Franz Josef Land on August 16 and 19, 2011. (Another sensor on Terra captured a wider view on August 17, 2011.)

The image above was made from a combination of visible and near-infrared wavelengths, and ice appears in shades of white and pale blue. The amount of sea ice filling the channels between the islands of Franz Josef Land varies from summer to summer. Captured toward the end of the Northern Hemisphere melt season, this shot shows a modest amount of sea ice on the ocean surface. Some of the ice has accumulated in bays like the one near northeastern Zieger Island.

Most of the ice in this scene is anchored to land, as large glaciers blanket the islands. Yet today’s glaciers are tiny compared to the ice sheet that dominated the region about 20,000 years ago. Studies of Franz Josef Land have actually contributed to a larger understanding of when that massive ice sheet began its slow retreat. Raised beaches, which preserve evidence of land rising as the crushing weight of overlying glaciers eases (known as isostatic rebound), were first recognized on the islands in the late nineteenth century. Researchers estimate that the giant ice sheet had retreated by about 10,000 years ago.

NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Caption by Michon Scott with information from Walt Meier and Ted Scambos, National Snow and Ice Data Center.

The Earth Observatory's mission is to share with the public the images, stories, and discoveries about climate and the environment that emerge from NASA research, including its satellite missions, in-the-field research, and climate models.

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