“Is anyone else out there? Are we alone?” Astronomer Seth Shostak addressed these frequently pondered questions on Thursday in his lecture “Life: A Cosmic Infection?” in Brooks-Rogers Auditorium. Shostak is the senior astronomer of the Search for Extraterrestrial Intelligence (SETI) Institute and recently published his newest book, Confessions of an Alien Hunter. Shostak’s lighthearted and often self-deprecating spirit captivated his audience as he discussed the possibility of life beyond the Earth.
After a warm introduction by Karen Kwitter, professor and department chair of astronomy, Shostak opened by saying that probably “nine out of 10” astronomers agree that intelligent life does exist in outer space, due to a “simple number argument” coming from the fact that there’s “a lot of cosmic real estate.” Shostak went on to inform the audience just how much is out there: 1022 stars are visible to our telescopes, the same number of glasses the water of all the world’s oceans would fill. But so far, no life, intelligent or not, has been found.
Shostak then described what he termed the “three-way horse race to find cosmic biology”: noticing it nearby, exploring it more and then finding evidence left by intelligence. The first two are mainly the work of the government’s NASA. Noticing activity involves sending probes to planets and moons in the solar system, such as Mars and Jupiter’s Titan, with the most famous example being the Mars Rovers. The second method is accomplished by simply looking for small, Earth-size planets in other solar systems. NASA’s Kepler Mission is a space telescope that was launched into space last March for the specific purpose of discovering distant planets that match the size of the Earth, hoping that these planets may sustain life. At this point, upon showing his first graph, Shostak jokingly remarked, “They say every time you show a graph you lose 10 percent of your audience. I have 12 graphs.”
The third component of the “horse race” is what concerns Shostak and his colleagues at the SETI Institute. The main focus of their activities is to “listen for extraterrestrials.” As Shostak described it, the SETI Institute basically “stares” at different star systems for several minutes then compares different readings to see if there any actual transmissions are coming from them. Shostak again addressed the issue of why no transmissions have yet been found by noting the SETI Institute’s funding and the fact that they’re looking for the proverbial “needle in a haystack.” However, major plans are underway to complete the Allen Telescope Array (named after major contributor Paul Allen of Microsoft fame) in Hat Creek, Calif., which will consist of 350 antennae dishes pointed to the skies. The popular image of alien-searching devices is one of gigantic dishes, yet cost efficiency has caused a shift to many smaller dishes in place of one gigantic dish. This view was largely popularized by the movie Contact, which Shostak served as a consultant for, although he was quick to note that they usually dropped his advice for more Hollywood-style drama.
Shostak then moved on, while jokingly apologizing for his “soporific presentation,” to the question of when we will discover signs of intelligent life. He was emphatic in saying that signs of extraterrestrial life will appear on Earth’s radar within the next half century, and cited different estimates ranging from 2014-2027. Shostak then bet the audience a free cup of Starbucks coffee that evidence would be found by 2025. He was quite skeptical about the idea that aliens were already here, saying the evidence supporting that theory is extremely limited. “We’ve been broadcasting our presence since about the end of World War II,” Shostak said, and again expressed his confidence that “no one knows homo sapiens exist.” Although the search has so far remained fruitless, “there’s always a bottle of champagne at the observatory” just in case, Shostak noted. But he added that “the bottle’s different every time – I blame the engineers,” to the laughter of the audience.
Shostak began his last topic, what potential aliens would look like, by saying, “Hollywood only has two kinds of aliens: the good kind that look like kids, and the bad kind that either abduct us or destroy the Earth.” He went on to say that of all these depictions “nearly all are anthropomorphic.” However, Shostak continued in a different vein, referencing the ever-accelerating process of increased power in computer technology, comparing the computers of the past to the almost incomparably faster ones of today. He said that “in the next generation or two we are going to invent our own successors,” meaning artificial intelligence in the form of our own machines. Due to this fact, Shostak found it to be almost certain that when we discover intelligent alien life, it will not in fact be living, but the mechanical successors of aliens.
Shostak concluded his lecture by quoting a Victorian writer who remarked that Europeans had broken a “watch-glass of isolation” surrounding previously undiscovered Australia. College students’ generation, Shostak claimed, would be the ones to see the watch-glass surrounding humans and the Earth broken.