Space Station Astronauts Marvel at Planet Earth

As Earth Day approaches, astronauts aboard the International Space Station (ISS) have a unique perch from which to gaze at their home planet and ponder its future.

NASA astronaut Garrett Reisman, an Expedition 17 flight engineer living aboard the space station, said the view of Earth from about 220 miles (354 km) up is both tremendous and precious.

?It?s fantastically beautiful from our vantage point,? said Reisman, who is making his first spaceflight, in a recent televised interview. ?The other thing that really strikes you is how thin the atmosphere is. It?s such a tiny little sliver of a band, and you get a definite impression of the fragility of it just by looking out the window at an angle.?

NASA is broadcasting a series of high-definition (HD) views of Earth recorded by astronauts from the ISS and the agency?s space shuttles to commemorate Earth Day on April 22, culminating with day-long HD broadcast on Tuesday.

Each continent on Earth has its own character and hue which veteran spaceflyers can recognize at a glance, Reisman said, adding that he hopes to gain such expertise during his flight.

Japan?s Kaguya orbiter, currently orbiting the moon, has also beamed back high-definition videos of a distant Earth rising and setting on the lunar horizon. The probe carries a special high-definition camera specifically designed to relay the stark beauty of the moon and Earth to the public, Japan Aerospace Exploration Agency officials have said.

Two of the three space station astronauts who returned to Earth Saturday agreed with Reisman?s description of the Earth from space.

Before leaving the station, Expedition 16 commander Peggy Whitson and South Korean astronaut So-yeon Yi told reporters that the Earth?s beauty was one of the highlights of their respective spaceflights. They landed early Saturday, off-target but safely, with Russian cosmonaut Yuri Malenchenko to end the six-month Expedition 16 mission.

?I do think there is a sense of fragileness to our planet just because of the thinness of the atmosphere,? Whitson said. ?It?s an incredibly beautiful place that we live in and this perspective that we have makes us want to cherish it even more.?

Yi, a 29-year-old bioengineer who became South Korea?s first spaceflyer during her 10-day spaceflight, concurred.

?We are all in a really beautiful world,? she said. ?So we should make our lives more beautiful.?

Click here for a button to access NASA TV feed on SPACE.com's ISS mission updates.

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