Jim Gray, the respected computer scientist who worked with big data before anyone had thought to call it that, was formally declared "missing and presumed dead" Friday by a San Francisco court, more than five years after his disappearance. Neither his remains nor any sign of his sailboat, the 40-foot, red-hulled Tenacious, have ever been found in the sea off San Francisco.
The death certificate was sought by his widow, Donna Carnes, to bring a measure of closure to "a strange, singular, rather painful mystery" in her life, as she termed it at a tribute to Gray on May 31, 2008. Long after the exhaustive Coast Guard search of 132,000 square miles of ocean ended, Carnes commissioned a search of her own.
She hired a sophisticated, side-scanning sonar team to map 300 square miles of ocean floor, along the 27-mile path between the Golden Gate bridge and the Farallon Islands, looking for a wreck matching Tenacious' dimensions. The sonar was sensitive enough to detect rocks and sandbars; it identified several sunken vessels, including at least two of the correct length. But an underwater robotic camera proved they weren't Gray's sailboat.
The death certificate was issued Wednesday. Afterward, Carnes sent a simple message to friends, according to the New York Times: "I am in the San Francisco house with the fire on, drinking tea, with the hope that Jim may rest in peace."
[Want to learn more about how friends of Jim Gray applied technology to try to locate him? See The Search For Jim Gray]
Gray set sail alone on Jan. 27, 2007, to scatter his mother's ashes at the Farallon Islands. Those familiar with both Gray and the route say he was an experienced sailor capable of executing the 12-hour trip by himself. On the other hand, a recent accident illustrated what can happen en route, even to experienced sailors.
The islands, also called the Farallones, exist at the edge of the continental shelf. Simon Crosby, former CTO of Citrix Systems and now co-founder of Bromium, once recalled being a crew member on a sailboat that struck an uncharted rock as it rounded the islands during a race.
In addition, the winds become tricky as they flow around a 347-foot high mountain on the largest Farallon, South Island. What starts as a predictable breeze from the east, which was the case on the day that Gray sailed, becomes a gust coming out of the north as you round the island's southern perimeter. And deep water swells, driven by storms in the Gulf of Alaska, mount the continental shelf near the islands, coming to the surface as big waves that arrive from seemingly out of nowhere.
The latter situation occurred in an incident last month, as a sailboat, similar in size to Gray's, rounded South Farallon Island during a race. The sailboat was struck by a massive wave that washed five of its eight-member crew overboard. As the remaining crew tried to regain control, a second wave seized the boat, spun it sideways, and carried it onto the rocks. Both a Coast Guard boat and helicopter were on the scene within the hour, but five crew members died in the mishap; one survivor likened the experience of floating in the water just off the rocky shore to being in "a washing machine filled with boulders. You don't really swim. The water took me where it wanted."
What happened to Gray? No one knows, but a single sailor, preoccupied with scattering his mother's ashes close to the rocks, might have put himself more at risk than he realized. If his boat struck a rock and sank suddenly on the far side of the islands, it may have been carried further out to sea along the ocean floor, entering the deep water ocean beyond Carnes' sonar search.
Even so, it remains unexplained why no distress signal ever came from a boat equipped with a radio. The Coast Guard confirmed that Gray's boat also carried an emergency position-indicating radio beacon that is automatically activated upon entering sea water. The beacon broadcasts a current position that is picked up by the Coast Guard. No signal was ever received.
The attempt to find Gray after he was reported missing involved many of his close research colleagues, former co-workers, and former students. At first, they refused to believe that Gray wouldn't be found. The shock of the Coast Guard calling off the search three days later pushed them into action. "Jim's high-powered group of friends included people who could re-target satellites," said Mike Olson, CEO of Cloudera, at a May 31, 2008, tribute at the University of California at Berkeley. Olson became the impromptu leader of a group of computer professionals and academics who decided to continue the search.
One former student, Werner Vogels, now CTO of Amazon Web Services, made Amazon's Mechanical Turk, a distributed workflow system, available to parcel out satellite images for volunteers to review. A satellite image consists of an immense, gray ocean image of 8,000 by 8,000 pixels. The Mechanical Turk could assign 400 by 400 pixel tiles of the master image to volunteers, who could then look for the off-color, 6-8 pixels that might represent a 40-foot boat. Several promising objects were identified, including one seen through thick cloud cover by Julian Bunn, a particle physicist at CalTech. Some possibilities beneath the cloud cover were cross-referenced with radar data from the Canadian space agency to establish an object's presence, a technique that Gray would have liked. Fly-over investigations proved the Tenacious was not among the objects.
Early Big Data Projects
Gray himself had pioneered big data techniques by accumulating geographic images into huge databases, such as TerraServer-USA, a rudimentary predecessor to Google Maps. He did the same for celestial mapping, creating the Skyserver database with terabytes of data on star positions for astronomers. At the time of his disappearance, he was talking to his friend, James Bellingham, chief technologist at the Monterey Bay Aquarium, about establishing a model of ocean currents and temperatures to be used in the attempt to better comprehend global warming.
Gray received computing's Nobel prize, the Turing award, in 1998. Beyond his research contributions, Gray was noted in technology research circles for his ability to share what he knew with others, draw ideas out of other people's work, and get small groups of researchers fired up about pushing the boundaries of what could be done.
"Jim looked you straight in the eye….He always listened to you. He worked a magic through an entire room. He seemed to care about so many people," said Pat Helland, co-researcher with Gray at Microsoft at the time of his disappearance, during the 2008 tribute. Berkeley computer science professor emeritus Michael Harrison said Gray had been a student of his who was "always coming up with new and original things. Couldn't this be done better," he recalled at the tribute. A Tandem Computers research associate, Wendy Bartlett, said Gray "was a great pollinator. He's go from person to person, spreading ideas around. He was an unusual mix of the academic and the pragmatic."
Michael Stonebraker, who developed the Ingres and Postgres database systems, described Gray as a pioneer of relational databases, thinking through the ACID properties that give a relational database transaction integrity. "Jim knew a lot about everything. He exemplified what it means to be a scholar," Stonebraker said at the tribute.
Many people who attended the tribute at Berkeley's Zellerbach Hall had known Gray personally. But not all of them. Terry Brugger, a young researcher at NASA Ames Research Center at the time and now a lead associate at Booz Allen Hamilton, said he attended because he had run across so many research papers with Jim Gray's name on them while studying databases at the University of California at Davis. "Their content still resonates quite strongly," Brugger said after the tribute.