Search For Life In Outer Space

Physical Science Ann Miller

Final Paper 2/23/06

The Search for Life in Outer Space

For years, astronomers, scientists of all kinds, and even average people have wondered if there is such thing as life on other planets. Many dedicate all of their time to researching extraterrestrial life. Some believe researching something we have no proof of is a waste of time.

Modern day telescopes have detected Earth-sized planets orbiting nearby stars. An ancient Martian rock shows signs of life, and scientists wonder if Jupiter's moon Europa contains life in its oceans. The idea that there is even a tiny hint of life that we share the universe with, not just living beings, but capable, intelligent life much like our own, opens new doors for further extensive research.

Spacecraft have explored all of the planets in our solar system except Pluto, and so far there are no signs of extraterrestrial life. Though no life has been found, there is no reason to give up a search for something out there we don't know about yet. Are certain scientists right in proposing that life originated on Mars, and could still exist today? It all remains up for debate.

To further one's education regarding life in outer space, knowledge of life and evolution must first be obtained. J.B.S. Haldane, a Scottish biochemist, and A.P. Oparin, a Russian biochemist, researched the formation of earth and concluded that "soon after the Earth's formation, the necessary chemical elements were present for complex molecules to form - molecules that are needed for life," (19-4). To assess the possibility that life exists now, or has at some point, on some other planet or moon, we have to know whether the conditions there are/were much like life as we know it on Earth. The first requirement for life is liquid water; without it, any kind of life, is impossible. But, how do we know what other life forms require to survive if we have never interacted with them? The same reasoning also applies to organic compounds. "Carbon-based polymers such as nucleic acids and proteins make up the core molecules required to carry out the central biological functions of replication and catalysis," (Wallace). Without these functions, life as we know it could not exist.

In 1990, a year after its launch, the Galileo spacecraft had circled the sun and flew within 960 km of Earth to give it the extra gravitational push it would need to reach Jupiter. It detected oxygen in the Earth's atmosphere, along with the