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Q&A March 2008

sputnikThe Soviet Union changed history when it launched Sputnik I on Oct. 4, 1957. The satellite was the size of a beach ball and weighed about 184 pounds. Image courtesy of NASA.

Q How have satellites improved in the last 50 years?
-- Submitted by 11th and 12th grade students at Francis Parker School, San Diego, Calif.

AAs you probably know, the first artificial satellite to orbit the earth was Sputnik, launched by the Soviet Union in October 1958. I was 5 years old then and remember the excitement of going outside after sunset and looking for the satellite passing overhead out in space.

Satellites were first launched during the Cold War, a period of tension, distrust, and competition between the United States and the Soviet Union. There was a looming threat the countries would launch nuclear weapons against each other if things got really bad. The United States and the Soviet Union developed satellites to spy on each other.

Initially pictures were recorded on film and sent back to Earth in a capsule with a parachute, which was then snatched in midair by an Air Force plane. There were only two film canisters per spacecraft so the spies had to be very selective about what was photographed.
launchIn February 2007, clouds of smoke form around the Delta II rocket with as it blasts off from Cape Canaveral Air Force Station. Onboard was the largest number of scientific satellites NASA has ever launched at one time. The satellites are tracking the North Pole.
About a decade later, President Lyndon Johnson publicly recognized that satellites could do so much more. "We've spent 35 or 40 billion dollars on the space program," Johnson said in 1967, "If nothing else had come out of it except the knowledge we gained from space photography, it would be worth 10 times what the whole program costs."

In the 1970s, new technology helped us see the earth even better. NASA's Landsat program beamed back spectacular, high-resolution images of the planet that helped scientists manage crops better, detect fault lines, and track weather events such as droughts, forest fires, and ice floes.

-- David Sandwell, geophysics professor, Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics


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Scripps Scientists take on questions from students curious about ocean and earth sciences


david sandwell

"In the 1970s, new technology helped us see the earth even better."
— Dr. David Sandwell