Today, the House Science and Technology Committee was told that within 20 years, the existence of alien life should be confirmed. According to a senior astronomer at the SETI Institute in California, Seth Shostak, there is an ongoing three-way race to learn whether or not life does exist either in this solar system or beyond. Most funding and efforts up until now have been focused within the solar system on Mars and outside the system on moons that could potentially have life.
One of the areas that astronomers would like to have greater opportunity to study is exomoons. An exomoon, like Endor in Return of the Jedi, is a potentially habitable moon that orbits an exoplanet. An exoplanet is a planet that orbits a star, excepting the one that Earth orbits. The first exoplanet was discovered in 1995 and since then, over 1,000 more have been identified. However, no exomoons have been discovered.
Kepler-186f is probably the most habitable planet discovered so far. Discovered by NASA’s Kepler satellite, it is one of five exoplanets that are orbiting a faint and small red dwarf star, in the constellation of Cygnus, 500 light years away. The earth-sized planet completes its orbit in 130 days. It is as far away from its star as Mercury is from the Sun. Because the red dwarf is quite a bit dimmer than the Sun, Kepler-186f gets about a third of the energy the Earth receives.
Hypothetically, because the exoplanet sits in what is called a “Goldilocks zone,” there is high potential for the existence of alien life forms on the planet. For example, in this solar system, Mars is too far away from the Sun and is therefore too cold. Venus sits too close to the Sun and is thereby too hot. Earth, however, has a temperature that is just right for the formation of life. Of course, other factors come into play, particularly the need for large bodies of water.
In this solar system, Shostak said, there are other worlds, perhaps as many as a half-dozen, that could potentially harbor alien life. He believes that the chances of making this discovery are good. Frankly, the outcome depends heavily on financing.
Another aspect of the search focuses on distant planets. Their atmospheres are scanned, looking for the telltale signs of life, methane and oxygen. On Earth, these gases are tied directly to the existence of life. Shostak said that these painstaking searches could also yield the desired result within two decades.
The third arm of this hunt is the work that is done at SETI. The Search for Extraterrestrial Intelligence partially involves capturing radio signals that are sent out from elsewhere in outer space. Whether by accident or design, it is hoped that SETI will detect these possible messages from other intelligent life. Shostak explains that since the invention of the radio in 1895, science has advanced so far that bits of information can be sent light years away.
For example, the first television show, the BBC’s The Man With the Flower in His Mouth, from 1930, would have passed over 10,000 stars by now. The Simpsons television show has been seen by nearby stars. Dan Werthimer, a celebrated SETI hunter, told legislators that it is a safe assumption that if Earth is broadcasting, perhaps there are other civilizations that are putting out signals as well, deliberately or otherwise.
Shostak was sure to clarify that simply because nothing has yet been found that does not mean that there is nothing to find. He added, “We have only just begun to search.” On November 20, SETI will be celebrating its 30th birthday. Perhaps they will be given the gift they have been seeking for their 50th birthday in 20 years: the discovery of alien life forms.
by Stacy Lamy