The International Space Station (ISS), the ninth one to be inhabited by crews, is the largest artificial satellite at present. Situated in the lower orbit of Earth, it provides a long term platform to conduct scientific research on various aspects including astronomy, astrobiology, physical sciences, weather in space and weather on Earth.
According to NASA, clear skies along with other favourable viewing conditions give astronauts on the ISS an opportunity to take outstanding satellite images of the planet. Cloudy or overcast skies inhibit the astronauts from taking good images. Here are few satellite images that have been taken by NASA on a clear day.
Kliuchevskoi Volcano, Kamchatka Peninsula
The image on the left, (fig.1), is an exceptional depiction of the eruption plumes stemming from Kliuchevskoi, an active volcano on the Kamchatka Peninsula. It was shot from an extremely oblique angle, making this piece look like a model of a mountain range. Generally satellite shots give a flattened look of the landscape. With a proper view of the shadows cast by the volcanic peaks, this one enhances our sense of three-dimensional topography.
Pavlof Volcano, Aleutian Arc
The striking pictures in (fig. 2,3) are of Pavlof Volcano. Taken by astronauts on May 18, 2013, these pictures reveal a three dimensional structure of the ash plume coming out of the volcano. This volcano in the Aleutian Arc discharged 6,000 meters high ash cloud extending up to the North Pacific Ocean.
Pavlof Volcano is one of the most active stratovolcano situated in the Aleutian Range of the Alaska Peninsula. The volcano entered the longest period of dormancy after its eruption in 1996. A fresh eruption triggered by seismic disturbances on August 15th, 2007, ended this period.
Cleveland Volcano, Chuginadak Island
Cleveland Volcano, on the Chuginadak Island, the largest in the subgroup of the Aleutian archipelago, is an active stratovolcano. Its layers are built of alternate layers of hardened lava, volcanic ash and volcanic rocks. Figure 4, taken by Flight Engineer Jeff Williams on May 23, 2006, shows the ash plume moving in the west-southwest direction.
The excellent pictures of Earth taken by the ISS are not only helpful for scientists but also the common people. These images help educate people about the movement of ash plumes and impact of volcanoes on weather.