How did life on Earth begin? Is there life beyond our planet? Is there a future for humankind on other planets? EXPLORING SPACE: THE QUEST FOR LIFE, airing on PBS Wednesday, March 22, 2006, check local listings, examines the search for life, from its origins on Earth to possibilities in space. Produced in high definition, the program features interviews with scientists who share their opinions about the possibility of life beyond Earth, and examines the latest developments in astrobiology, one of the hottest fields in science today. The quest for answers takes EXPLORING SPACE to earthly locales ranging from Greenland to the mountains of eastern Mexico, from a French vineyard to a research facility in Japan - as well as deep into outer space. From a trip through space alongside a city-sized meteor to a walk on the surface of Mars with the first crew to explore the Red Planet, spectacular computer-animated imagery creates a viewing experience that will bring audiences as close to space as possible without leaving home. Earth may be a rare environment uniquely designed for nurturing living organisms, but as humans explore the creation of the planet, the realization grows that the answers to the origins of life may lie beyond earthly bounds. The program begins in Greenland, where Dr. Stephen Mojzsis of the University of Colorado examines some of Earth's oldest rock. Because early Earth's surface was not rich in organic compounds, but space is, Mojzsis believes that material from space played a role in the development of life on our planet. In EXPLORING SPACE, scientists including University of Washington astronomer Dr. Donald Brownlee, U.C. Berkeley astrophysicist Dr. Richard Muller and Arizona State University organic chemist Dr. John Cronin discuss the evidence they've found supporting a link between life on Earth and deep space. The same cosmic processes that may have helped life arise on Earth also could be seeding life elsewhere in the universe - including our own solar system. Images sent back by the U.S. space probe Galileo indicate that Europa, one of the moons of Jupiter, is covered with ice, presenting the possibility of a huge ocean lying below; though frigid, that ocean could be a wellspring of alien plants and animals. NASA astronomer Dr. Richard Terrile says Europa is potentially "a very, very exciting biological target." The search for life in the universe is not restricted to one distant, icy moon. EXPLORING SPACE looks at our longtime fascination with our nearest planetary neighbor, Mars, and examines what it would take for humans to get there. One challenge facing travelers aboard a spacecraft using chemical propellants would be the sheer amount of time - 12 to 14 months - spent in space. The experiences of former Soviet cosmonauts reveal the effects that prolonged periods in space can have on humans, from the impact of zero-gravity conditions on bone and muscle mass to psychological stress. Dr. Valery Polyakov, a cosmonaut who lived aboard the Mir Space Station for 438 days - setting a world record for time spent in space - recalls experiencing "petulance and obsessive fear" while on Mir. EXPLORING SPACE shows how the introduction of a simple activity - gardening - helped Mir occupants find relief from the emotional and mental strain of living in space. What would a space traveler find upon reaching the Red Planet? EXPLORING SPACE shows viewers a Mars that is similar to Earth in some ways, but very different in others. NASA's unmanned missions to Mars have revealed tantalizing signs that liquid water once existed there - and even minute amounts of water can be enough for tenacious life forms to take hold, as astrobiology pioneer Dr. E. Imre Friedmann attests. Friedmann has found microorganisms in some of the world's harshest environments - places that rival the extreme cold of Mars. "Life," he says, "is present in very unlikely places," including deep beneath the Earth's surface, where microbial colonies flourish with no sunlight. Dr. Karsten Pederson of Sweden's Goteborg University believes that these microorganisms subsist on energy from gas that is formed deep below Earth's surface. "If there is a possibility of life living under the surface of a planet as there is on Earth," says Pederson, "and if this life lives by getting its energy from the planet itself instead of the sun, the existence of life on other planets becomes quite probable." What forms might life beyond Earth take? Viewers meet Joel Hagen, a NASA artist who uses scientific data to envision what extraterrestrial life forms might look like, and intelligence expert Dr. Lori Marino of Atlanta's Emory University, whose study of the elevated brain power of marine mammals such as dolphins has led her to believe that if intelligent life exists beyond Earth, it will have evolved skills humans may not even recognize. EXPLORING SPACE looks at the work of the SETI (Search for Extra Terrestrial Intelligence) Institute, which is using the world's biggest antennas to hunt for a particular kind of radio signal from deep space - the kind produced by transmitters. SETI senior astronomer Seth Shostak believes that goal could be achieved relatively soon: "I'll go out on a limb and say that we're going to succeed, not 100 years from now, not 1,000 years from now ... but in the next two to three decades." In its quest for life beyond Earth, EXPLORING SPACE again turns to Mars. University of Washington atmospheric sciences expert Dr. David Catling states, "If we look at planets elsewhere in the galaxy, elsewhere in the universe, around other stars, then the prospect of there being life on those planets would, I think, be improved greatly if we know that life had evolved and originated on Mars as well." Ultimately, the only way to know if life exists on Mars, or whether humans could live there, is for humans to travel there. Scientists including University of Washington astronomer Dr. Adam Bruckner, former NASA astronaut Dr. John Connolly and University of Arizona aerospace engineering expert Dr. K.R. Sridhar discuss the likely costs of such a mission, and how those costs could be reduced - for instance, by having the astronauts produce most of the consumables needed for their stay on Mars using materials available on the planet itself. Mars is blisteringly cold, devoid of oxygen and vegetation, and subject to howling dust storms - yet some believe that the planet could be made suitable for human habitation. In EXPLORING SPACE, NASA's Dr. Christopher McKay cites evidence that early in their history, Mars and Earth were much more alike - which he believes makes the Red Planet a good candidate for terraforming. McKay theorizes that the same emissions that threaten Earth with global warming could be used to thaw out Mars, and that the process of making Mars suitable for life could be accomplished over a 50- to 100-year period. Others, including Adam Bruckner and David Catling, believe that a Mars makeover, if even possible, would take a very long time, given the technical challenges involved. McKay and forest and plant specialist Dr. Rafael Navarro-Gonzalez of the National Autonomous University of Mexico envision the creation of a Martian environment in which trees and plants would not only survive but, by producing oxygen, help transform the planet's carbon dioxide atmosphere. Life from Earth would change Mars' environment, but it also would be changed by that environment, evolving in ways different from life on Earth. As EXPLORING SPACE reveals, human physiology could be affected in a variety ways by life on low-gravity Mars - so much so that over time, it might be more accurate to identify Martian humans as a species different from Earth humans. Humans have developed the knowledge and technology to take the next steps in a journey through the solar system - but given the problems facing Earth today, many question the wisdom of spending billions of dollars to explore space. Humans soon will need to decide how important it is to uncover the mystery of what lies beyond our planet.
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