Columbus camera captures its first views of Earth
One of the experiments housed on Columbus, now part of the International Space Station, is an automated eye in the sky known as the Earth Viewing Camera (EVC). Now, after several weeks of troubleshooting by the EVC team in the Netherlands, the first pictures from the orbiting camera have arrived safely back on Earth.
The initial image, showing a dimly illuminated cloud-covered region, was successfully downloaded on 6 March. A second picture (see right) ̵1; the first to be produced on command from the ground ̵1; was taken soon after dawn on 7 March and shows a scattering of white and pink clouds close to the Aleutian Islands in the north Pacific.
"It was really exciting to see the first image arriving from space after the long period of developing the camera and testing it in orbit," said Massimo Sabbatini, ESA Principal Investigator for the EVC. "We are just starting to experiment with the various camera parameters to adjust for the vast range of lighting conditions we encounter. That's why the second picture is slightly blurred," explained Sabbatini. "The ISS is travelling at about 7km per second, so we have to adjust the exposure time to compensate for this rapid motion. At that speed the camera moves over hundreds of metres on the ground in a matter of milliseconds."
The EVC points continuously at a fixed angle toward the Earth. The camera weighs 7.8kg and measures 0.4 x 0.28 x 0.16m. It uses a commercial, off-the-shelf sensor provided by Kodak, with a 2k x 2k detector. It is able to capture colour images of the Earth's surface that cover an area of 200 x 200km.
Located on the starboard side of the International Space Station, Columbus sweeps around the Earth once every 90 minutes. Since the Station's orbital path is inclined at about 52 degrees to the equator, the Earth Viewing Camera has the potential to take pictures of anywhere on the Earth's surface from England to the southern tip of South America. This includes almost all of the densely populated parts of the world.
On 7 February 2008, the European Columbus laboratory was launched with the STS-122 Shuttle mission on Space Shuttle Atlantis. Columbus is now an integral part of the International Space Station (ISS).
Image: A photo from Columbus laboratory's Earth Viewing Camera (EVC) - the first to be produced on command from the ground [Credit: ESA/CGS]