In November 2017, at the initiative of Douglas Vakoz, the president and founder of the organization METI (Messaging Extra-Terrestrial Intelligence), a message was sent from Earth to the star GJ 273, located just over 12 light-years away. The message contains elements of mathematics, music, and science—in case it falls into the hands of an intelligent civilization capable of registering and interpreting it, we might expect a response as early as 2042.
Vakoz is an astrobiologist and psychologist who is involved in the search for extraterrestrial intelligence. In 2015, he founded METI, based in San Francisco. The goal of this organization is to send messages to potential intelligent beings in the universe and to build an interdisciplinary community that will create messages in accordance with the evolution of intelligence and language, thereby maximizing the likelihood that the message will be understandable to a species with no connections to Earth.
The desire to establish communication with extraterrestrial intelligent life is even older than radio technology. The German mathematician Carl Friedrich Gauss proposed clearing Siberian forests in the shape of a triangle large enough to be seen from space, with grain planted at its center to create a contrast of colors. Such a structure would need to be large enough to be visible from the Moon or Mars, and the geometric figure could only be interpreted as an intentional construction. Joseph von Littrow suggested digging a circular canal, 30 kilometers in diameter, which would be filled with kerosene and glow at night. The French poet and inventor Charles Cros had the idea of directing powerful light towards our satellite or Venus using mirrors, while Francis Galton even resolved to create a coding system that takes into account that other civilizations may not have a base-10 numbering system like ours.
All of the above represents ways to inform the inhabitants of other planets that Earth is home to thinking beings. However, how do we construct a message that is understandable to a civilization about which we know absolutely nothing? On one hand, it can be discouraging that we have not even mastered the language of animals that have always been with us; on the other hand, there is hope in the possibility that we may find common ground with a technologically advanced species that understands universal languages such as mathematics, numbers, frequencies, and waves. Additionally, there must be a way to express temporal relations, quantities, and possibilities of negation.
Douglas Vakoz emphasizes that METI messages are special because they take into account the minds of those who might be seeking distant intelligence from other planets. Repeating the message three times a day over a span of three days gives extraterrestrial scientists the opportunity to verify the signal. Vakoz asserts that “the last thing we want is to send aliens a Wow! Signal that is only captured once and never repeated.” In 1977, Dr. Jerry Ehman from the SETI Institute detected a signal that was 30 times stronger than the surrounding electromagnetic radiation, but despite numerous checks and observations, it did not reappear. For decades, it was believed to be evidence of extraterrestrial intelligence, until 40 years later when astronomer Antonio Paris solved the mystery, explaining that it was two comets passing the same trajectory.
In his book “Communication with Extraterrestrial Intelligence,” as well as in numerous papers, Vakoz explains the fundamental mistakes and principles of sending interstellar messages. According to him, the mistake lies in the fact that most previous messages attempted to explain and convey too much, making them difficult to interpret. METI messages focus on key scientific and mathematical concepts, such as basic arithmetic, triangles, and sine waves. If a civilization is capable of radio astronomy, it must understand that 1+1=2. Once basic communication is established, one can begin to build upon it and search for a common language.
Professor Michael Arbib from the University of Southern California believes that the question of how to design a message that is understandable to beings completely different from us, who may not even have the sense of sight but can hear waves, is quite insignificant. The messages we send are not the product of a single mind, but a collection of knowledge from many people in symbiosis with the technology we currently possess. He suggests that it may actually be easier to find a commonlanguage with an anthropomorphic robot than with most organic beings in the cosmos. In any case, we can only hope that we will have plenty of ideas to share, not only regarding the physical universe but also concerning the diversity of social structures.
The most famous message ever sent into space is that on the Voyager probe’s golden record. Among other things, it contains greetings to aliens in 55 different languages, music from great composers, sounds of animals inhabiting the Earth, and 116 photographs from Earth.
The first radio message, consisting of just 1,679 bits, was transmitted by the Arecibo radio telescope in 1974. This number was not chosen randomly; it was used because it represents the product of two prime numbers and, if the message were displayed on a coordinate grid, it would consist of a series of simple images. The message was directed at the star cluster M13, located in the constellation Hercules.
Once the ice was broken, a series of messages with varying content began to emerge. In 1986, Joe Davis, an artist and researcher at the Massachusetts Institute of Technology, sent the most controversial message into space, which contained sounds of vaginal contractions from a ballerina. The message was sent to only two stars, Epsilon Eridani and Tau Ceti, instead of the four originally planned, because the U.S. Air Force, which oversaw the project, decided to halt it. Nonetheless, the message reached Epsilon Eridani in 1996 and Tau Ceti in 1998.
The message “Cosmic Call 1” was sent in 1999 and was based on mathematical and scientific concepts considered universal. Four years later, the Cosmic Call was repeated, but this time it included five additional stars. The content of the message consisted of photographs and other multimedia material. The costs of sending it were covered by a company with grander plans: to launch a spacecraft equipped with a solar sail carrying hair samples, photographs, and other objects. However, the company went bankrupt, and the project ended up being limited to just the message.
In February 2008, NASA celebrated a birthday by sending The Beatles’ song “Across the Universe.” In the same year, a six-hour message containing an advertisement for tortillas was broadcast toward the star 47 Ursae Majoris, while the science fiction film “The Day the Earth Stood Still” was sent toward Alpha Centauri. The aforementioned Joe Davis sent the genetic code for the enzyme RuBisCo, which is fundamental to photosynthesis and the most abundant protein on Earth, the following year.
Finally, a question many scientists raise is whether it is wise to reach out to unknown civilizations that may be technologically incomparably more advanced than us and whether it is appropriate for some scientists to do so without consulting the public or engaging in public discourse. Douglas Vakoz responds by asserting that we have been announcing our presence since the moment we emitted our first radio signal, whether we wanted to or not. Any technologically advanced civilization within a radius of 123 light-years that has been listening to this part of the sky has no doubt about whether Earth is inhabited or not.