Bradford Smith, who extended humanity’s vision to look boldly where no eyes had ever looked as head of the camera team for the Voyager mission, hopscotching from one weird world to the next across the solar system and discovering prospects for alien life, died on July 3 at his home in Santa Fe. He was 86.
His wife, Diane McGregor, said the cause was complications of the autoimmune disorder myasthenia gravis.
From 1979, when Voyager 1 first shot past Jupiter, to 1989, when its twin, Voyager 2, cruised past Neptune, it was Dr. Smith, an avuncular, gravelly voiced astronomer, who stepped in front of the space press at the Jet Propulsion Laboratory in Pasadena, Calif., every morning, showed new postcards from outer space and confessed that he and his colleagues were baffled by what they were seeing.
Why were there dark spokes across the rings of Saturn? Why are there no craters on its moon Enceladus or the Jovian moon Europa?
“We now find ourselves at a point where we had hoped not to be,” he said in one typical comment in 1981, confessing that scientists had no viable explanation for the complex configurations in Saturn’s rings.
“Voyager was an odyssey,” said Carolyn Porco of the Space Science Institute in Boulder, Colo., who worked on the mission. “It was more mythic than scientific. He was the lead pilgrim, and he was great at it.”
Dr. Smith, who spent most of his career at the Lunar and Planetary Laboratory and Steward Observatory at the University of Arizona, was a pioneer in using electronic detectors, such as the silicon chips known as CCDs now at the heart of cameras and smartphones, that were replacing photographic plates in telescopes.
Friends and colleagues said that hidden inside a somewhat gruff and intimidating exterior was a kid who occasionally came out during the Voyager press briefings. Asked once what he would say to Galileo if he were there, Dr. Smith said he would ask him how he had gotten so old.
Bradford Adelbert Smith was born on Sept. 22, 1931, in Cambridge, Mass., the oldest of three sons of Percival and Mary Smith, and grew up in nearby Winchester, where his ancestors had been farmers. His father ran a leather tanning business, and McGregor said a young Dr. Smith spent a lot of time cleaning tanks, which fueled an early interest in chemistry and in building bombs, leading at one point to a visit from the FBI.
But his first love was astronomy, and he often rode his bike to the Harvard College Observatory.
Misled by the leather patches on Harvard astronomer Fred Whipple’s jacket into thinking that scientists led lives of genteel poverty, he chose to major in chemical engineering at Northeastern University, graduating in 1954 with a bachelor’s degree.
That same year he married Tamara Ushakoff, a former high school and college classmate. That marriage ended in divorce, as did a second marriage, to Susan Armstrong. Besides McGregor, an artist in Santa Fe, he is survived by three children from his first marriage, Kari Rasmason, Hillary Tolmen, and Randall Smith; five grandchildren and five great-grandchildren.
After college he joined the Army and was assigned to be the liaison to a group of astronomers led by Clyde Tombaugh, famous as the discoverer of Pluto, that was searching for satellites of the moon. Following his service, he went to work with Tombaugh at New Mexico State University, becoming director of planetary research.
In 1958, he and Tombaugh initiated the first program to photograph the brighter planets in a routine systematic way, but that was only a gateway drug to the solar system. His cameras and devices went to Mars on the Mariner 6 and Mariner 7 spacecraft, and he was the deputy leader of the imaging team on Mariner 9, which became the first spacecraft to orbit another planet when it slipped into place around Mars in 1971.
All this before he had attained a doctorate. Advised by a NASA friend that he would not get anywhere without one, he finished a dissertation and was awarded his doctorate, New Mexico State’s first in astronomy, in January 1973.
At about the same time he was named leader of the imaging team for the Voyager mission, an ambitious project to send a pair of probes to the outer solar system, taking advantage of rare planetary alignment to slingshot the probes from one planet to another, starting with Jupiter.
Nobody knew what to expect. The best astronomical images of more distant planets such as Uranus were only a few blurry pixels wide, and no one knew how many moons or rings were circling them.
Suspecting that the moons and rings of these planets might be as fascinating as the planets themselves, the newly minted Dr. Smith pressed NASA to increase the focal lengths of the Voyager cameras and the imaging plans to provide for higher resolution of the rings and moons. He then added scientists with expertise in geology and planetary rings to the imaging team NASA had selected, as well as foreign scientists.
The results spoke for themselves: Jupiter in 1979, Saturn in 1980 and 1981, Uranus in 1986, and finally Neptune in 1989, Voyager’s final passage.
“It was the closest thing to being on the bridge of the Enterprise,” Richard Terrile of the Jet Propulsion Laboratory said.
Under the gaze of Dr. Smith’s cameras, nature revealed propensities and potentials undreamt of on Earth in what had been thought of as the frozen silent depths of time. The strangely smooth moons such as Europa and Enceladus are now known to be shells of ice covering gigantic oceans. Saturn’s moon Titan has lakes and methane dunes.
Far from being a realm of dead, scarred ice cubes, the moons of the outer solar system became the most promising abodes now known for life beyond Earth.
“The wide range of unexpected findings is due both to the real differences between the outer and the inner solar system and to the depth of our prior ignorance,” Dr. Smith concluded in an article for the journal Science. “The sense of novelty would probably not have been greater had we explored a different solar system.” In an interview for a documentary released last year, “The Farthest,” Dr. Smith said, “We did something really, really great.”
Voyager 2 passed Neptune in 1989, completing the interplanetary saga. Chuck Berry, whose music was carried on a record on the spacecraft, performed at a celebration at Caltech.
Dr. Smith retired from the University of Arizona in 1991 and moved to the Big Island of Hawaii, where he did research for the University of Hawaii.
He loved Hawaii, but in 2001 McGregor persuaded him to move to Santa Fe, where they became involved in rehabilitating wounded and orphaned wildlife. “Brad was an expert at handling raptors — he could handle a bald eagle by himself,” McGregor said in an e-mail.
While the Voyagers sailed through space, Dr. Smith never stopped working and observing from the ground. In 1984, using a coronagraph to mask the central glare from the bright star Beta Pictoris, he and Terrile recorded the image of a disk of dust circling the star. It was the first image of a so-called protoplanetary disk, the stuff from which planets are thought to condense.
“That was the home run,” Terrile said. The result, he said, opened the door to the study of alien planetary systems, known as exoplanets, which is now the fastest-growing area of astronomy.
Dr. Smith went on to help develop a new detector for the Hubble Space Telescope, designed for infrared studies of dust and exoplanets.
The ubiquitous Dr. Smith also participated in a Soviet mission to send a pair of Vega spacecraft past Halley’s comet in 1986. The spacecraft finally pierced the cometary veil of dust and shining glitter gas and produced the first image of the comet’s nucleus. It looked like a black peanut about 10 miles long with a jet of light coming off one end.
Examining the image a few weeks later in a laboratory in Budapest, Dr. Smith had occasion to reflect on the price of knowledge.
Halley’s comet had been terrifying humanity for thousands of years with its feathery, glowing visage. Now it had been reduced, like the Wizard of Oz with the curtain yanked away, to a cosmic mighty mite.
“The other side of planetary exploration is that the romance is lost,” he said. “Objects like Halley’s comet have a romantic mystique. You see them up close and they still have scientific interest, but they lose their mystery.”
“Poor Halley,” he sighed, “has joined the ranks of being just another celestial body instead of a phenomenon.”