STOCKHOLM - Three researchers based in the U.S., U.K. and Switzerland won the Nobel Prize in Chemistry on Wednesday for developing a way to create detailed images of the molecules that drive life - a technology that the Nobel committee said allowed scientists to visualize molecular processes they had never previously seen.

The 9-million-kronor ($1.1 million) prize is shared by Jacques Dubochet of the University of Lausanne, Joachim Frank at New York's Columbia University and Richard Henderson of MRC Laboratory of Molecular Biology in Cambridge, Britain.

The Royal Swedish Academy of Sciences said their method, called cryo-electron microscopy, allows researchers to “freeze biomolecules” mid-movement. The technology “is decisive for both the basic understanding of life's chemistry and for the development of pharmaceuticals,” it said.

For instance, the academy said the technique was used when scientists began suspecting the Zika virus was causing the epidemic of brain-damaged children in Brazil. Images of the virus allowed researchers to “start searching for potential targets” for Zika drugs.

Frank said he was “fully overwhelmed” on hearing he had won.

“I thought the chances of a Nobel Prize were minuscule because there are so many other innovations and discoveries that happen almost every day,” he said. “So yes, I was in a way speechless.”

He said he hasn't yet thought about what to do with the prize money, but added: “I was telling my wife that we don't have to worry about a dog sitter anymore.”

American Chemical Society president Allison Campbell said the technology is like “the Google Earth for molecules.”

“This discovery allows the scientist to zoom in down to the fine detail (giving) that fine resolution that you want to have,” she told The Associated Press. “Having all the exquisite detail just gives you a wealth of information about that protein molecule and how it is interacting with its environment.”

Nobel chemistry committee member Heiner Linke added: “It's the first time that we can see biological molecules in their natural environment and how they actually work together down to the individual atoms.”

Electron microscopes once were thought to be useful only for examining nonliving material because the electron beam destroys biological material. But cryo-technology - freezing material at extremely low temperatures - protected the examined material from damage.

Dubochet's contribution was to freeze the water in the sample being examined so quickly that it vitrified - forming a kind of glass rather than ice, whose crystalline structure diffracted the electron beam.

Frank developed mathematical models to sharpen fuzzy electron microscope images and Henderson, in 1990, was able to generate a 3-D image of a protein at atom-level resolution.

The annual prize rewards researchers for major advances in studying the infinitesimal bits of material that are the building blocks of life.

Recent prizes have gone to scientists who developed molecular “machines” - molecules with controllable motions - and who mapped how cells repair damaged DNA, leading to improved cancer treatments.

It's the third Nobel announced this week.

The medicine prize went to three Americans studying circadian rhythms: Jeffrey C. Hall, Michael Rosbash and Michael W. Young. The physics prize went to Rainer Weiss, Barry Barish and Kip Thorne for detecting gravitational waves.

The literature winner will be named Thursday and the peace prize will be announced Friday.

Malcolm Ritter in New York and Bob Lentz in Philadelphia contributed to this story.

This version corrects the spelling of Jacques Dubochet's last name in the 12th paragraph.