תיאורISS019E014918 Saint Helena Island.jpg | English: This astronaut photograph shows the island’s sharp peaks and deep ravines; the rugged topography results from erosion of the volcanic rocks that make up the island. The change in elevation from the coast to the interior creates a climate gradient. The higher, wetter centre is covered with green vegetation, whereas the lower coastal areas are drier and hotter, with little vegetation cover. Français : Photo de l'île de Sainte Hélène prise par un astronaute de la NASA. On peut voir les pics élevés de l'île et ses ravines profondes. Cette topographie accidentée résulte de l'action de l'érosion sur les roches volcaniques dont l'île est constituée. Le changement d'élévation entre la périphérie et le centre de l'île créé un gradient climatique: le sommet est plus frais et humide, il est couvert de végétation. Les côtes, plus chaudes et sèches, laissent apparaitre la roche nue. ISS Crew Earth Observations: ISS019-E-14918 Identification | Mission | ISS019 (Expedition 19) | Roll | E | Frame | 14918 | Country or Geographic Name | ATLANTIC OCEAN I(S). | Features | ST HELENA I., JAMESTOWN, DIANA PK., FOR., RAVINES | Center Point Latitude | -16.0° N | Center Point Longitude | -5.7° E | Camera | Camera Tilt | 6° | Camera Focal Length | 400 mm | Camera | Nikon D2Xs | Film | 4288 x 2848 pixel CMOS sensor, RGBG imager color filter. | Quality | Percentage of Cloud Cover | 11-25% | Nadir What is Nadir? | Date | 2009-05-07 | Time | 08:37:05 | Nadir Point Latitude | -15.7° N | Nadir Point Longitude | -5.5° E | Nadir to Photo Center Direction | Southwest | Sun Azimuth | 62° | Spacecraft Altitude | 193 nautical miles (357 km) | Sun Elevation Angle | 26° | Orbit Number | 3952 | Original image caption | Saint Helena Island, located in the South Atlantic Ocean approximately 1,860 kilometers (1,156 miles) west of Africa, was one of the many isolated islands that naturalist Charles Darwin visited during his scientific voyages in the nineteenth century. He visited the island in 1836 aboard the HMS Beagle, recording observations of the plants, animals, and geology that would shape his theory of evolution. This image was acquired by astronauts onboard the International Space Station as part of an ongoing effort (the HMS Beagle Project to document current biodiversity in areas visited by Charles Darwin. This astronaut photograph shows the island’s sharp peaks and deep ravines; the rugged topography results from erosion of the volcanic rocks that make up the island. The change in elevation from the coast to the interior creates a climate gradient. The higher, wetter center is covered with green vegetation, whereas the lower coastal areas are drier and hotter, with little vegetation cover. Human presence on the island has also caused dramatic changes to the original plants and animals of the island. Only about 10 percent of the forest cover observed by the first explorers now remains in a semi-natural state, concentrated in the interior highlands. Saint Helena Island is perhaps best known as the final resting place of Napoleon Bonaparte I of France. Bonaparte was exiled to the island following his defeat at the Battle of Waterloo in 1815; he died on the island six years later in 1821. Today, the island is a British Overseas Territory, with access provided thirty times a year by a single ship, the Royal Mail Ship St. Helena. | |