The island of Hawaii is home to four volcanoes monitored by volcanologists: Mauna Loa, Hualalai, Kilauea,
and Mauna Kea. Mauna Kea is depicted in this astronaut photograph; of
the four volcanoes, it is the only one that has not erupted during
historical times. The Hawaiian Islands chain, together with the
submerged Emperor chain to the northwest, forms an extended line of
volcanic islands and seamounts that is thought to record passage of the
Pacific Plate over a hotspot (or thermal plume)
in the Earth’s mantle. Areas of active volcanism in the southern
Hawaiian Islands today mark the general location of the hotspot.
This detailed astronaut photograph illustrates why the volcano is called Mauna Kea (white mountain in Hawaiian). While the neighboring Mauna Loa volcano is a classic shield volcano
comprised of dark basaltic lava flows, Mauna Kea experienced more
explosive activity during its last eruptive phase. This covered its
basalt lava flows with pyroclastic deposits.
In addition, former glaciers at the summit of the volcano left till
deposits—sediments deposited directly in place as the glacial ice
melted. The majority of these deposits are visible as light brown areas
to the north and southeast of the white snow at image center. Numerous
small red to dark gray cinder cones
are another distinctive feature of Mauna Kea. The cinder cones
represent the most recent type of volcanic activity at the volcano.
Astronaut photograph ISS019-E-11922
was acquired on April 28, 2009, with a Nikon D2Xs digital camera fitted
with a 400 mm lens and is provided by the ISS Crew Earth Observations
experiment and the Image Science & Analysis Laboratory, Johnson
Space Center. The image was taken by the Expedition 19 crew. The image in this article has been cropped and enhanced to improve contrast. Lens artifacts have been removed. The International Space Station Program
supports the laboratory to help astronauts take pictures of Earth that
will be of the greatest value to scientists and the public, and to make
those images freely available on the Internet. Additional images taken
by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption William L. Stefanov, NASA-JSC.