Photos: Soaring ambition for solar aircraft

Adventure and exploration seem to be in the family DNA for Piccard, shown here as a child with his father and grandfather.

Grandfather Auguste Piccard devised the principles behind both the stratospheric balloon and the pressurized cabin. Flying a pressurized, hydrogen-filled balloon into the stratosphere, he reached an altitude of 15,780 meters, or 51,771 feet, in 1931 and 16,201 meters, or 53,152 feet, in 1932. Using the same concept of pressurization, he later invented a submarine called the Bathyscaphe Trieste, and in 1953, dove beneath the sea with his son Jacques to a depth of 3,150 meters, or 10,334 feet.

Jacques Piccard followed in the family footsteps by developing underwater vehicles to study the ocean depths. Traveling in the Bathyscaphe Trieste, he and co-pilot Lt. Don Walsh are still the only two people to have reached the deepest point underwater, diving to a distance of 10,916 meters, or 35,813 feet, in 1960. He later explored the Gulf Stream with another submersible vessel that he invented. Piloting the mesoscaphe Ben Franklin, he and his crew stayed underwater for a month, providing a test study for the effects of such a lengthy journey on human beings. NASA has long incorporated research from this mission in planning its space flights.