Astrobiology grant

University scientists experiment on origins of organic compounds

Bruce Fegley, Ph.D., and his colleagues in the Planetary Chemistry Laboratory here will conduct experiments on the origin of organic compounds in the solar nebula, the cloud of gas and dust from which the sun, Earth and other objects in the solar system formed. Fegley’s group will use the experimental results and other data to model how impacts by comets and asteroids may have supplied organic materials to Earth during its early history.

Current thinking suggests that such impacts provided some of the organic compounds necessary for the origin of life.

Bruce Fegley is professor of earth and planetary sciences in Arts & Sciences, and a member of the National Aeronautics and Space Administration’s Goddard Astrobiology team.

The University was recently selected as one of 12 new nodes on NASA’s Astrobiology Institute (NAI) for the next five years. Fegley will oversee the University research, which is funded for $350,000 over five years.

Some of Fegley’s prior work suggests that at least some of the organic compounds in comets and asteroids were formed by reactions called Fischer-Tropsch reactions, which produce organic compounds from hydrogen and carbon monoxide gas using catalysts such as magnetite, an iron oxide. The presence of magnetite in primitive meteorites formed from the solar nebula suggests that magnetite was present in the solar nebula.

The Germans used Fischer-Tropsch reactions to produce gasoline in World War II and the same process is used to produce gasoline in South Africa today. Fegley and his group want to see if conditions were right in the inner solar nebula billions of years ago for the organic compounds to form and be incorporated into asteroids and comets.

The NAI research will combine laboratory experiments, observations with ground-based telescopes and spacecraft, and sample comet and asteroid material to discover how organic molecules are created in interstellar clouds and later are modified in the gas and dust disks around young stars. These disks, called protoplanetary disks, form when an interstellar cloud collapses.

While collapsing interstellar clouds are busy building solar systems, lumps of ice and dust (comets) form in the cold, outer regions of the protoplanetary disk that surrounds a newly forming sun. Like “dirty snowballs,” comets trap large amounts of organic molecules in their ices as they form a protoplanetary disk.

Astronomers think the newly created Earth was subjected to a fierce bombardment of comets about 4 billion years ago, when the protoplanetary disk that created our solar system was thick with swarms of newborn comets. The rain of comets was so intense that it could have supplied a large portion of the water in Earth’s oceans.

The NAI is a virtual institute, in which collaborations and communication of results will be conducted by videoconferences over the Internet, as well as at scientific conferences. Workshops at Goddard Space Flight Center and the University of Maryland will share results with educators and students under the Minority Insti-tution Astrobiology Cooperative.

The interdisciplinary team includes researchers in earth science, space science and instrument development at Goddard, as well as scientists from around the country and the world.

Institutions with scientific co-investigators include NASA’s Goddard; the University of Maryland; the California Institute of Technology; Johns Hopkins University’s Applied Physics Laboratory; the SETI institute, Mountain View, Calif.; Eckerd College; the University of Massachusetts; and the University of Washington.

Institutions with scientific collaborators include the Carnegie Institution of Washington, Washington, D.C.; NASA’s Ames Research Center, Moffett Field, Calif.; the University of California, Santa Cruz; The Catholic University of America; and Rowan University.

International collaborators include scientists from the University of Paris; and Leiden Observatory, the Netherlands.