If aliens are out there, the United Kingdom is determined to find them, as seen in the recent launch of a network called the UK Search for ExtraTerrestrial Intelligence (UKSETI), which combines the efforts and know-how of academics from 11 institutions from across the country.
The UK Seti Research Network (UKSRN), according to a presentation at the National Astronomy Meeting on July 5, is designed to cover a broad range of research topics, including potential methods for detecting signals, the linguistic challenge of deciphering messages, the probability of an extraterrestrial civilization interacting with Earth and the longevity of civilizations.
Given these array of challeges, Alan Penny, the coordinator of UKSRN, explains that the network isn't just for the professionals.
"We hope that the existence of the network will excite interest from people in the UK astronomical community that have been thinking about SETI and encourage them to contribute their work," he said in a press release, adding that the NAM presentation was directed at "presenting the whole range of UK SETI activities to the community" in hopes of promoting "a wider understanding of, and activity in, this subject."
Tim O'Brien from the University of Manchester's Jodrell Bank Observatory described at the meeting the capability of the UK's recently commissioned e-MERLIN array of seven radio telescopes for SETI projects and reported on progress in initial test observations.
The first proposal to search for radio signals from civilizations located on other words was inspired first by the construction of the Lovell Telescope, O'Brien explained. Located in northwest England, the telescope has kept watch on the universe for over 50 years now. However, as is often the case, astronomers faced technological barriers that handicapped their studies - a barrier that has slowly degraded over the years.
"We went on to take part in the SETI Institutes's Project Phoenix from 1998 to 2003, searching for signals from about a thousand nearby stars," O'Brien explained. "At that time, the equipment required to sift through the data was expensive and unusual, but our modern telescopes are potentially capable of conducting these type of observations as a matter of course."
The e-MERLIN array, which includes the Lovell Telescope, is connected by optical fibers and spread over 130 miles (217 kilometers) from Jodrell Bank to Cambridge, offering a new approach for distinguishing true extraterrestrial signals from interference generated here on Earth - an issue that has long plagued SETI projects.
"It's early days for this new SETI work at Jodrell but we think that using e-MERLIN, and future facilities such as the Square Kilometre Array, we could make an important contribution to the search for intelligent life elsewhere in the universe," O'Brien said.
John Elliott of Leeds Metropolitan University is a researcher on the nature of communication, and specifically how language structure can be identified and methods for subsequent decipherment and dissemination. Having analyzed over 60 human languages in addition to non-human communication, including robots and dolphins, Elliot believes it may be possible to develop strategies for decoding any potential extraterrestrial messages, though such a task would no doubt prove highly challeging.
"Suppose SETI succeeds and we detect a technological beacon," he posited. "Any message is unlikely to be written in Martian English, so standard decipherment/decryption techniques used by the military and security agencies are not going to help much. To put the challenge into context, we still have scripts from antiquity that have remained undeciphered over hundreds of years, despite many serious attempts."
However, even before the deconstruction of unearthly languages can even begin, scientists must first locate evidence of it - evidence that someone (or something) living is reaching out to Earth.
Back in 1950 during a conversation on the search for alien life, the great physicist Enrico Fermi posed the simple question, "Where is everybody?"
The question points to a paradox between the high estimates for the probability of the existence of extraterrestrial civilizations and the lack of contact or evidence.
According to Anders Sandberg of the Future of Humanity Institute at Oxford University, in answering this question it's important to start with investigating how far away in space and time a civilization could start and still have a chance of interacting with Earth today.
"If this were a very limited range, the Fermi question, 'Where are they?' would be easy to answer: they couldn't have got here yet," he explained. "However, we show in our paper that, beyond a certain technological level, civilizations can spread not just across their own galaxy but across enormous intergalactic distances."
Ultimately, he estimates there are likely millions or billions of galaxies from which a civilization established early on in the history of the universe could reach Earth.
"If life or intelligence is rare, it must be millions or billions of times rarer; if advanced societies wipe themselves out, or decide to not go exploring, they need to converge to this outcome with extremely high probability, since it only takes one that escapes this fate to fill the universe," Sandberg said.
Meanwhile, the work of Dr Austin Gerig, senior research fellow in Complex Networks at the University of Oxford, estimates the fraction of civilizations in the universe that are long-lived along with analyzing the human race's prospects for survival.
"We know that (1) we exist and that (2) our birth number within our civilization is approximately 70 billion (i.e., approximately 70 billion people were born before us)," he writes. "From such little information, we can reasonably, and perhaps surprisingly, conclude that (1) many other civilizations exist and that (2) most of these civilizations are small, i.e., most will die out before producing trillions of people."
In his research, Gerig focuses on a specific consequence of this reasoning called the "universal doomsday argument," which states that long-lived civilizations must be rare because if they were not, humanity would find itself living in one.
"If most civilizations are small, then our own civilization is likely to be small, i.e., it is likely to die out within the next few centuries. Our research indicates this is the case, but that our estimates of survival are greater than previously thought using a more traditional form of the doomsday argument," Gerig said.
Duncan Forgan from the Royal Observatory Edinburgh has opted for yet another way to locate extraterrestrial life: detecting large structures built by civilizations on other planets orbiting stars of their own. Thanks to the Kepler Space Telescope, which has detected a whole host of new exoplanets, the scientist has no shortage of places to start searching.
"While the odds of seeing megastructures are probably very low," Forgan admits, "we will soon have a huge archive of exoplanet data to search for these objects - at no extra cost to SETI scientists. We may detect the presence, or remains, of an alien civilization that felt the need to move their star!"