Note to Editors: Bruce Jakosky will give a free public talk about his new book at the ¶¶Òõ¶ÌÊÓƵ Museum on Oct. 7 at 7 p.m. Refreshments will be provided.
The potential for the evolution of past or present life in the universe reaches beyond Mars and even our own solar system, according to a University of Colorado at Boulder space scientist.
Bruce Jakosky, a scientist at ¶¶Òõ¶ÌÊÓƵ-Boulder's Laboratory for Atmospheric and Space Physics, said new findings over the past decade indicate life could have been present on Venus in the distant past when the sun was cooler, that life may now be present on Jupiter's moon Europa, and it may have developed on several other planets or moons harboring water. Recent planet discoveries outside the solar system are tantalizing hints that life could have formed elsewhere, he said.
Scientists believe the requirements for primitive life forms like bacteria are water or some other type of liquid, a source of energy, and access to elements to construct complex molecules, said Jakosky, a professor in geological sciences. "If life can form as easily as we believe it did on Earth, we should find evidence of it on Mars and perhaps other planets and moons."
The implications of studying the earliest history of life on Earth are that microbial life can form relatively easily under the right conditions, said Jakosky. Actual searches for life on these other planets will be used to test the theories.
He discusses these issues and the potential for life elsewhere in his new book, "The Search for Life on Other Planets," published this month by Cambridge University Press.
"The search for life on other planets has undergone a rebirth in recent years," he said. "Although the scientific impetus has come from significant new discoveries in biology and astronomy, the search itself is driven by the human desire to explore," he said. "I think the most significant aspect of what is happening today in the space sciences is that we are actively looking for life elsewhere.
"Exploration is the driver, and I think a lot of people want to understand what it means to be human," said Jakosky.
According to Jakosky, three major discoveries in the past 500 years have had huge impacts on space exploration. The discovery by Copernicus in the 1500s that Earth orbited the sun and was not the center of the universe; Charles Darwin's work on evolution in the 1800s, which essentially removed humans from the center of life on Earth; and the discovery of planets elsewhere in the universe.
"We are living in a unique time," he said. "In the past three years, we have discovered about a dozen planets outside our solar system, and there will be more to come. The challenge now is to find new techniques to see if Earth-like planets are present out there." To date, the planets discovered outside the solar system are Jupiter-sized or larger, but new techniques are being developed that may be able to detect Earth-sized planets, he said.
"There is tremendous interest on Earth about extraterrestrial life," said Jakosky, the new director of LASP's Center for Astrobiology. ¶¶Òõ¶ÌÊÓƵ was selected in July as one of NASA's 11 new Astrobiology Institutes that will focus on interdisciplinary research on life in the universe. The ¶¶Òõ¶ÌÊÓƵ-Boulder center is funded by a five-year, $3 million NASA grant.
Jakosky also is teaching an undergraduate class on extraterrestrial biology this semester that filled quickly with students majoring in a wide variety of topics, from philosophy, physics and music to anthropology and economics. "They all are interested in finding out whether there is life elsewhere," he said.
The discovery of strange, primitive forms of bacterial life on Earth in recent years that live in near-boiling hydrothermal vents undersea or in volcanically active areas is a revolution, he said. "There is no reason that organisms like these could not exist in similar environments that occur on other planets," he said.
Jakosky's new book is divided into three parts: what we know about the origins of life and evolution on Earth; a look at planets and moons in our own solar system for life potential; and the formation of planets around other stars and assessing their potential for microbial or intelligent life.
"Twenty years ago, we thought there was only one planet in the solar system capable of supporting life," said Jakosky. "Now we know there may be as many as a half-dozen. We are the first generation in history with any real chance of discovering life elsewhere. Jakosky's book will be in bookstores in October 1998.