A Journey to the Edge of Interstellar Space

A supersonic wind from the Sun creates a giant bubble called the heliosphere that envelops all of the planets. Launched in 1977 on a journey to explore Jupiter, Saturn, Uranus, and Neptune, the two Voyager spacecraft are now racing to leave the bubble called the heliosphere and enter interstellar space. The two spacecraft are 8 and 10 billion miles from Earth, exploring the outermost layer of the bubble where the supersonic solar wind abruptly slows in a sonic shock as it presses outward against the surrounding interstellar matter. In another five years, Voyager 1 will likely cross the boundary of heliosphere, becoming our first interstellar probe immersed in matter from the supernova explosions of other stars.

Edward C. Stone is the David Morrisroe Professor of Physics at the California Institute of Technology (Caltech) and Vice Provost for Special Projects. He was Director of the Jet Propulsion Laboratory (1991-2001), and a Caltech Vice President.

Since 1972, Stone has served as the chief scientist for the Voyager Mission at the Jet Propulsion Laboratory. Following launch of the twin Voyager spacecraft in 1977, he coordinated the efforts of eleven teams of scientists in their studies of Jupiter, Saturn, Uranus and Neptune.

As Vice Provost for Special Projects, he has also chaired the board of directors that oversees the design development of the Thirty Meter Telescope (TMT) on behalf of Caltech, the University of California, and the Association of Canadian Universities for Research in Astronomy (ACURA). Stone is a member of the National Academy of Sciences, the American Philosophical Society, president of the International Academy of Astronautics, and a director of the W.M. Keck Foundation.

Professor Stone’s visit to CMC is sponsored by the Joint Science Department.