Eugene Shoemaker; Astronomer, Co-Discoverer of Comet

Eugene Shoemaker, an astronomer and geologist who was a co-discoverer of the Shoemaker-Levy 9 comet that collided with Jupiter in 1994, was killed Friday in a traffic accident near Alice Springs, Australia.

The Lowell Observatory at Flagstaff, Ariz., with which Shoemaker was most recently associated, said the 69-year-old scientist died in a two-car accident.

His wife, Carolyn, who frequently did research with him, suffered broken ribs in the accident and was hospitalized in stable condition in Alice Springs, the Lowell announcement said.

The couple had arrived in Australia six days before to research some of that continent’s impact craters, one of Shoemaker’s specialties in a career of studying interplanetary subjects.

“We count Gene as one of the great founders of planetary science and the person who practically invented our knowledge of the impacts of comets and asteroids on Earth and in the solar system in general,� said Edward Bowell, acting director at Lowell Observatory.

Shoemaker was a professor of geology at Caltech for 16 years, and had received both bachelor’s and master’s of science degrees there before getting his PhD at Princeton in 1960. Since 1993, he has been a scientist emeritus with the U.S. Geological Survey.

In his career, he became associated with the theory that an asteroid colliding with the Earth was responsible for the extinction of the dinosaurs 65 million years ago.

Shoemaker also was involved in the effort to identify asteroids that might collide with the Earth, although he expressed the view that the biggest and most dangerous have already been discovered.

By 1993, Shoemaker and his wife had discovered 27 comets.

But their chief fame came from their discovery, along with colleague David Levy, of Shoemaker-Levy 9.

When that comet was broken up by tidal forces from Jupiter, and fragments collided with the planet in July 1994, photographs of the collisions taken by the Hubbell space telescope mesmerized scientists and laymen alike with their spectacular demonstration of the explosive power of such encounters.

Shoemaker also carried out pioneering work on the nature and origin of Meteor Crater near Winslow, Ariz., helping to provide a foundation for research into craters on the moon and on other planets.

Shoemaker took part in the Ranger space missions, was principal investigator for the television experiment on the Surveyor lunar landers from 1963 to 1968 and led the geology field investigations team for the first Apollo lunar landings in the 1960s.

However, in 1969, Shoemaker announced that he was leaving the space program “out of deep concern for [its] direction.�

He explained that he thought more could be obtained at a reasonable expense by sending unmanned missions to the moon and to other planets.

The Apollo missions to the moon, he said, were basically a transportation system rather than an exploration system. The same results could have been obtained earlier and at one-fifth the cost, he said.

In another endeavor, Shoemaker founded the Branch of Astrogeology of the Geological Survey in Flagstaff, and acted as its director from 1961 to 1966.

In his work at Lowell Observatory in the last four years, Shoemaker was active in the Clementine mission that imaged the moon and was science team leader in the Clementine 2 mission that will examine two or more near-Earth objects close up.

Shoemaker was also asked by NASA in 1994 to chair a working group on surveying near-Earth objects. As early as 1973, he had initiated the Palomar Planet-Crossing Asteroid Survey to delineate the asteroid threat.

Shoemaker was born in Los Angeles on April 28, 1928. His first major project was exploring for uranium deposits and investigating salt structures in Colorado and Utah from 1948 to 1950.

By 1957, he was beginning the major work of his life, doing research on the structure and mechanics of meteorite impact and nuclear explosion craters.

In addition to his wife, Shoemaker is survived by his three children, Linda, Patrick and Christy. No services have been announced.