Figure 11.32 Typical Habitat of Sulfolobus Sulfur hot spring in Yellowstone National Park.
Astrobiology: The Search for Life on Other Planets
2f life as we know it exists on other planets, one form it will take will likely be microbial. The task, then, is to figure out how to find and detect such extraterrestrial microorganisms. Considering that we still know relatively little about the microbial life on our own planet, coupled with the extreme difficulty of obtaining or testing extraterrestrial samples, this is a daunting challenge with many as yet unanswered questions. For example, what is the most likely source of life on other planets? What is the best way to preserve specimens for study on earth? What will be the culture requirements to grow such organisms? Astrobiology, the study of life in the universe, is a new field that is bringing together scientists from a wide range of disciplines, including microbiology, geology, astronomy, biology, and chemistry, to begin answering some of these questions. The goal is to determine the origin, evolution, distribution, and destiny of life in the universe. These astrobiologists are also given the task of developing lightweight, dependable, and meaningful testing devices to be used in future space missions.
Astrobiologists believe that within our solar system, life would most likely be found either on Europa, a moon of Jupiter, or on Mars. This is because Europa and Mars appear to have, or have had, water, which is crucial for all known forms of life. Europa has an icy crust, beneath which may be liquid water or even a liquid ocean. Mars is the planet that is closest to earth, and it has the most similar environment. Photographs suggest that flowing water once existed there. Besides missions to both these bodies, NASA also has future plans to return material from both a comet and an asteroid.
To prepare for researching life on other planets, microbiolo-gists have turned to some of the most extreme environments here on earth. These include glaciers and ice shelves, hot springs, deserts, volcanoes, deep ocean hydrothermal vents, and subterranean features such as caves. Because select microorganisms can survive in these environs, which are analogous to conditions expected on other planets, they are good testing grounds for the technology to be used on future missions.
Was this article helpful?