If DART had been available 63 million years ago, dinosaurs could still roam the earth. DART stands for Double Asteroid Redirection Test, NASA’s project to determine whether a rocket launched from Earth can alter the course of an asteroid by colliding with it.
When dinosaurs (along with millions of other species) became extinct as a result of an asteroid collision, life on earth was changed forever. It could be again if a large asteroid is directly hit. Meanwhile, the possibility of life on other planets continues to intrigue scientists and laymen alike.
If life is beyond Earth, scientists known as astrobiologists will want to study all living things. The first discoveries may just be microscopic organisms. Ecological research extends to life that we cannot see with the naked eye.
An astrobiologist asks questions such as: Can life be created from chemical compounds? What are the processes required to do this? Can life travel from one planet to another? If so, how? Today’s technology brings us closer to solving such mysteries.
The field of astrobiology involves a conglomerate of already established scientific disciplines such as oceanography, chemistry, and microbiology. Geneticists, ecologists and geologists will also be involved to answer questions that will arise.
An age-old question that can now be addressed by astrobiologists is how did life on Earth begin? With the advent of space travel, scientists might be able to answer a modern extension of this question: Can we find evidence of similar conditions on other planets in our own solar system or elsewhere in the galaxy?
Extreme environmental conditions are not an insurmountable obstacle to life on another planet. Even in our own world, creatures live in sea depths far beyond sunlight and at unimaginable pressures. Fish and worms thrive around deep ocean thermal vents of volcanic origin, where sulphides serve as a source of chemical energy.
Live bacteria can be found in toxic waste landfills, and even larger organisms live under the ice of Antarctica. Just because humans can’t live in such harsh environmental conditions doesn’t mean that life can’t exist. Life can take many forms.
Astrobiologists today keep their feet on the ground, but their children and grandchildren may well have theirs on other planets. Space shuttles have already reached Mars and manned missions seem possible. Imagine landing on another world where water is known to occur and from which life has even been reported.
Astroecology, a subset of astrobiology, has great potential as a field of science. If we discovered living extraterrestrial organisms, the questions to ask would be limitless. Where do they feed? How do they convert food into energy? How do they reproduce? How did they get to where they are?
Ironically, environmentalists have yet to answer these questions for most of the plants and animals that share this world with us. However, looking for answers on other worlds is very appealing to some scientists.
Eventually, we’ll have to consider what happens if scientists find out about life on other planets. Will we want space researchers to come back to Earth after looking for life on another planet? Could they bring back with them living entities, intentionally or not, in the form of microorganisms or another virus that could spell the death knell for humans?
It might be better if they share their findings with us and then enjoy their stay.
With the development of manned space travel, we will face ethical dilemmas similar to those we face with transgenic vegetables, cloning, and test tube babies.
The questions posed by such dilemmas are as limitless as the universe. But if we are to live in this universe, we have to keep looking for answers. Determining if we can change the trajectory of a small asteroid is one more step in the conquest of space and determining if astroecology could one day be a field of scientific study.
Whit Gibbons is Professor of Zoology and Senior Biologist in the Savannah River Ecology Laboratory at the University of Georgia. If you have an environmental question or comment, email firstname.lastname@example.org.