It was a time of world tension.

Two world powers faced off against each other in a Cold War that used fear as a weapon and spurred both a nuclear arms race and a race for space as the United States and the Soviet Union vied for scientific and technical superiority not only in weapons and machines but in intelligence as well.

At a quiet center of the quest for information was Edward Miller of Castine, who, as a research engineer with General Electric Corp. working on the top-secret Corona Project, was a key figure in the development of America’s first generation of spy satellites.

Outstripping the capabilities of the nation’s high-level balloon imagery of the 1950s and the better-known U-2 spy planes, the Corona satellites secretly brought back precise, close-up photographs that showed Soviet nuclear capabilities and placements during the height of the Cold War.

They also established a satellite-imaging capability that still assists Earth-based researchers in mapping, natural resource explorations, meteorology, archaeology and geology.

Miller, now 84, and four other lead engineers on the Corona Project, which was declassified in 1995, were honored recently in Washington, D.C., with the Charles Stark Draper Prize, the highest honor bestowed by the National Academy of Engineers.

The honor carries with it a weighty gold medal and a $500,000 cash prize that the five engineers will share.

Miller joined the project in 1959 as the lead developer of the re-entry vehicle for the Corona satellites. It was his team that designed the systems to recover the first man-made object to return from Earth orbit.

The vehicle had to withstand not only the pressures of lift-off and the cold of space, but also the high temperatures of re-entry. And it had to do it well enough to protect the canister of film it carried.

These were the days before digital cameras and beaming images back to Earth. The Corona images were captured on specially designed film and had to be brought back to Earth in-tact to be of any use.

The team developed a heat shield that could be jettisoned, a parachute that could be deployed, and a telemetry signal and strobe lights that would turn on after re-entry so an aircraft could locate the satellite, snatch it in midair by its chute cords and haul it onboard.

“We never doubted it would be successful, even though some fairly prominent scientists were saying it couldn’t be done,” Miller said recently. “I never believed that, even though we knew it was going to be trial and error to some extent. We were working on the Model T’s of satellites. And we were the last of the slide-rule and T-square engineers.”

All his work was done amid the highest security and secrecy. Although the project had a public face, known as the Discovery Project, the public was unaware that Corona was financed through the CIA and that its primary mission was to photograph military sites in the Soviet Union and China, and later in Cuba.

The Cuban images provided President Kennedy the precise information he needed during the Cuban Missile Crisis, Miller said.

“Kennedy was able to stand Khrushchev down because he had hard and fast images of Cuba at the time,” he said.

The more than 800,000 images the Corona project brought back to Earth showed the military capabilities of the Soviet Union and allowed the United States to track developments in Russia and China.

The images also eased national security concerns that the Russians had leapt ahead in the arms race.

In 1967, President Lyndon Johnson, quoted in a Smithsonian Institution book about the Corona Project, said that if nothing else had come from the space program, the knowledge gained from the space photography was worth 10 times the cost of the whole program.

“It turns out our guesses were way off,” Johnson said. “We were doing things we didn’t need to do; we were building things we didn’t need to build; we were harboring fears we didn’t need to harbor. Because of the satellites, I know how many missiles the enemy has.”

The first 12 Discovery-Corona missions, however, ended in failure. But on Aug. 12, 1960, the 13th flight proved to be a qualified success, and the tale of its recovery reads like a high seas adventure.

Due to heavy clouds and fog, the Air Force plane missed capturing the satellite and it landed in the Pacific Ocean. Navy ships were on patrol in the area and sped to the site.

“There were Russian trawlers in the area, too,” Miller said. “They said they were trawlers, but they were signal intercept ships tracking American satellites in hopes of recovering one of them.

“There was a real race to see who would get there first. We had an Air Force B47 in the area that flew over the trawler at deck level trying to convince them to turn away. But the Russians ignored them and kept coming.”

In the end, the Navy got there first and a Navy frogman fished out the vehicle and its payload.

A few weeks later, Discovery 14 accomplished a midair capture, the first of many as the Corona-Discovery project flew 146 missions during the next 12 years, most of them successful and most logging midair recoveries.

Although the project was highly compartmentalized, Miller had access to the Corona photos, both those taken over Russia and China, and those from test flights over the United States. One photo, taken from 120 miles up, he said, clearly showed Fort George in Castine and the Millers’ summer home nearby.

Miller tried to get a copy of that photo, but officials at the time feared it might be identified as a satellite photo and expose the project.

Since President Clinton declassified the project and the images in 1995, however, Miller said he has heard that photos the Corona satellite took of the Kremlin during the Cold War era are now being handed out to tourists who visit Moscow.

Miller spent 50 years in research and development, including work on the Voyager missions to Mars, which, he pointed out, provided the images used to select the landing sites for the latest Mars mission, which sent two rovers to explore the Red Planet. Miller also served as an assistant secretary of the Army for research and development.

But his work on the Corona Project remains a highlight of that career.

“We knew we were doing something immensely important for the country, more important in terms of national security than the landing on the moon, which was getting all the publicity,” he said. “We knew we were making an impact that we would have never had a chance of making as a private citizen.”