MADRID, 11 (EUROPA PRESS)
If an alien technological civilization heard any transmission from Earth, it would take around 3,000 years to get an answer.
It is the calculation of the Harvard astronomers Amir Siraj and Abraham Loeb, who addressed the question – in a study published in arXiv -, following the example of the Copernicus Principle, which establishes that humanity and the Earth are representative of the norm (and not an outlier). Loeb recently launched an initiative to search for techno-signatures of civilizations in space.
In this study, Siraj and Loeb focused on a particular aspect of SETI, which they called the Search for Extraterrestrial Response Intelligence (SETRI). By this, they refer to extraterrestrial intelligences that would be motivated to send messages to Earth in response to the detection of technological activity on our planet. This addresses an issue of growing importance to the SETI community.
In short, does humanity ever have the chance to hear of a cyclization in another world before ours collapses or is wiped out by a natural disaster? As Siraj told Universe Today via email:
“It is important to estimate the response time of extraterrestrial response intelligences (ETRI), as such an estimate informs the nature of effective SETI searches, as well as the implications of a confirmed signal if we ever receive one. The question we address The answer in our article is: when can we expect our first cosmic conversation to take place? “
This establishes the first parameter of their study, which was the amount of time that humanity has been emitting detectable signatures. Of all the possible technology firms that have been considered to date, the most likely and the most investigated by SETI researchers remain radio broadcasts. In accordance with the Copernican principle, we can assume that the ETIs are also engaged in the search for intelligence signals other than their own.
“The Copernican principle states that it is unlikely that we will live in a privileged time and therefore the probability that another habitable planet like Earth is going through an analog of our first century of radio communications right now, given a few thousand out of millions of years of its history, it is down one part in ten million, “Loeb said. “Therefore, a response is expected only within a large enough volume, containing more than ten million stars.”
It can also be safely assumed that an advanced civilization from another world would see radio signals as a possible technological signature and would be actively listening to them. The first long-range radio transmission took place in 1901, when Italian inventor Guglielmo Marconi sent the first transatlantic transmission from Cornwall, England, to St. John’s, Newfoundland. Since then, humans have been sending radio transmissions into space without thinking about the consequences.
This means that if there is a civilization 100 light years from Earth with sensitive radio telescopes, they may have already heard of us. In short, we may have already “started a conversation” with an intelligent species and are just waiting for a response. Beyond this, Siraj said, they left with a number of parameters that were consistent with the Copernican Principle and the conditions under which life is known to flourish:
“We consider that extraterrestrial intelligence can communicate through electromagnetic radiation, located on Earth-like planets that orbit stars similar to the Sun (also known as ‘life as we know it’). Additionally, we consider radio signals ( than at the speed of light) as well as physical probes, which would travel more slowly.We use the Copernican principle, which is inherently optimistic about the prevalence of life in the Universe, to set a lower limit on the expected response time.
Transmission technologies can extend beyond radio waves to include other types of electromagnetic (EM) radiation, such as microwave lasers, X-rays, gamma rays, and more. Since the only limitation is the speed of light (299,792,458 m / s (1,079 million km / h) is still the fastest option available. It also means that humans would only have to wait until the 22nd century to receive a transmission of a civilization located a hundred light years away.
Assuming that our galaxy is relatively homogeneous in terms of the distribution of stars in its disk, this results in a volume of one billion cubic light years or one thousand light years in any direction. This, in turn, implies a round trip time of more than two thousand years. This basically means that if an otherworldly civilization is aware of us and wants to talk, we would not hear from them until 4,000 AD at the earliest.
“We found that the fact that we have only existed as a technological civilization for about a hundred years means that, at this point, we should not expect to hear from an extraterrestrial civilization in response to our own signals. In other words, it is extremely unlikely that we will be able to initiate a cosmic conversation, “Siraj summarized.