Norwegian Fringes

The animation, which is based on an interferogram generated with two radar images captured by Sentinel-1A in ‘Interferometric Wide-Swath’ mode on 11 and 23 August 2014, mainly shows topography around the northern coast of Norway. Although Sentinel-1A is still being commissioned, this new result demonstrates how useful it will be to map the shape of the land and monitor ground movement. Synthetic aperture radar interferometry – or InSAR – is a technique where two or more satellite radar images acquired over the same area are combined to map topography and detect surface changes. Small changes on the ground cause changes in the radar signal phase and lead to the rainbow-colored fringes of an ‘interferogram’. In this case, the animation denotes differences in topography.

Since the area around the Lyngen Alps is particularly prone to landslides, it is closely monitored. Large landslides that suddenly shift rock into the sea could potentially create tsunami-like waves. In 1810, such a wave destroyed a village, and, history shows that this kind of natural disaster occurs a couple of times every 100 years in Norway. InSAR is an important tool used by the Norwegian authorities to map rockslide hazards nationwide. The unprecedented coverage offered by the Sentinel-1 mission will significantly increase the value of InSAR data for this purpose.

Video credit: Copernicus data (2014)/ESA/Norut–SEOM Insarap study (video animation data: Norwegian Mapping Authority and NASA)

Note: For more information, see Norway Relief. For similar images, one featuring northwestern Italy and part of Corsica and the other featuring Mount Etna on the island of Sicily, see New Views From Sentinel-1A and Etna Slopes, respectively.

Italy

Astronauts on the International Space Station fly over our planet at around 300 km altitude. From that distance it is not always easy to distinguish countries and cities – political borders cannot be seen from space. This image however clearly shows Italy’s distinctive outline as it contrasts with the blackness of the Mediterranean Sea at night.

The lights to the north of Italy that houses much industry stop more or less at the border with France, Switzerland and Austria. The cities of Turin and Milan show up brightly, as do Rome and Naples further to the south.

The island of Sicily can be seen at the bottom-right of this image with Italy’s other large island, Sardinia, to the left. Above, and almost touching Sardinia, is the island of Corsica that is not part of Italy.

The line of lights following the northern contours of the Mediterranean Sea is the French coastline known as the ‘Côte d’Azur’ or French Riviera.

The thin green line following Earth’s curve is our atmosphere that keeps us warm, protects us from the Sun and cosmic rays as well as the vacuum of space. These images from space show how populated and industrialized Europe is and the enormous impact humans have on our planet.

Photo credit: ESA/NASA

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: