The idea that we are not alone in the vast expanse of the universe is both thrilling and terrifying. While many say we have yet to definitively prove the existence of extraterrestrial (ET) life, we at the Extraterrestrial Communication Group vehemently disagree. We are not talking about just microbial life; we are also talking about advanced intelligent life and any stage of development in between. But how do we unquestionably prove it beyond contestation? How much proof do we really need.”
Proof and evidence, two crucial elements in academic research, are often used interchangeably. However, they have a distinct difference. Proof is the information or data that demonstrates the truth of a statement beyond a reasonable doubt, while evidence is any information that supports or weakens a belief, proposition, or hypothesis. It’s the responsibility of researchers to grasp this distinction, as it’s essential for presenting their findings and arguments effectively.
Recall from the movie Jaws, Hooper’s statement to the mayor of the town:
“I think I am familiar with the fact that you are going to ignore this problem until it swims up and bites you in the ass.”
Here are the ECG’s top 5 answers to the question about definitive proof of ET existence.
- Direct Observation
Obviously, the most straightforward way to prove the existence of extraterrestrial life is through direct observation. This could involve detecting microbial life on another celestial body or observing an ET visitor here. In recent years, missions like NASA’s Mars Rover have been scouring the Red Planet for signs of past or present life. If microbial life was discovered on Mars, it would be a groundbreaking moment in human history and provide strong evidence for the existence of extraterrestrial life.
Closer to home, there have been many documented direct observations of UFOs, obviously not from Earth. Many are easily discredited. However, many are not. These reports come from reputable and reliable sources, including highly trained military personnel. They are also well documented in government disclosure files available to the public. This does not even consider historical reports going back thousands of years. The corpus of information is immense. Case closed.
- Detection of Biosignatures
Biosignatures are molecules or features that indicate biological activity. For example, the presence of certain gases like oxygen or methane in an exoplanet’s atmosphere could suggest the presence of life. Scientists can analyze the spectra of these gases to determine their composition and potential sources. In 2019, astronomers detected water vapor in the atmosphere of K2-18b, an exoplanet in its star’s habitable zone. While this discovery does not prove the existence of life, it is a promising step towards identifying potentially habitable alien worlds.
- Communication Signals
Another way to prove the existence of extraterrestrial life is through the detection of communication signals. SETI (Search for Extraterrestrial Intelligence) is an organization that scans the skies for radio signals or other transmissions from advanced alien civilizations. While we have yet to detect any definitive signals from extraterrestrial beings, the search continues. Discovering a clear and deliberate signal from an alien civilization would provide proof of extraterrestrial life.
We at the ECG believe there is a reason for this lack of signal reception. A message has been left for us to discover, and we need to respond consistently with the 3-way communication procedure. Stephen Silva, founder of the ECG, has published two books on this topic: “Extraterrestrial Communication Code” and “Angel Communication Code.”
- Fossils or Artifacts
If extraterrestrial life existed in the past on Mars or elsewhere, fossils or artifacts could be preserved in the rock layers of these planets. Scientists have found structures on Mars that resemble stromatolites, fossilized microbial mats found on Earth. While these findings are not conclusive evidence of past life on Mars, they raise intriguing possibilities.
- Multiple Lines of Evidence
Ultimately, discovering extraterrestrial life may require multiple lines of evidence to establish its existence beyond a reasonable doubt. By combining direct observations, biosignatures, communication signals, and fossil or artifact discoveries, scientists can build a compelling case for the existence of alien life. In the event of a breakthrough discovery, multiple independent sources must confirm the findings to eliminate any doubts or skepticism. Collaboration between different scientific disciplines and organizations will be essential in verifying the discovery of extraterrestrial life.
The following is taken directly from an article published onPhysics.org.
Provided by The Conversation. Read the original article.
In the past few decades, several phenomena have led to excited speculation in the scientific community that they might indeed be indications that there is extraterrestrial life. It will no doubt happen again.
Recently, two very different examples sparked excitement. In 2017, it was the mystery interstellar object “Oumuamua.” In 2021, it was the possible discovery of the gas phosphine in the clouds of Venus.
In both cases, it seemed possible that the phenomenon indicated some kind of ET biological source. Notably, physicist Avi Loeb from Harvard University argued that the oddly shaped “Oumuamua” was an alien spaceship.
Phosphine in the atmosphere of a rocky planet is proposed to be a strong signature for life, as it is continuously produced by microbes on Earth.
These are just two of the latest cases in a long list of examples of such initially promising phenomena. Although a few of the examples are still controversial, most have other explanations (it wasn’t aliens).
How can we be sure we’ve reached the correct conclusion about something as subtle as the presence of a certain gas or a strange-looking space rock? Our new paper, published in Astrobiology, proposes a technique for reliably evaluating such evidence.
The word “possible” is strange, with a rather unfortunate degree of flexibility. There’s a sense that I may meet King Charles III today, but at the same time, it is doubtful.
Many shouts of: “It might be aliens!” should be interpreted in this (strained) sense. By contrast, we often use “might” to express something highly probable, such as “it might snow today.”
The concept of possibility incorporates these extremes and everything in between. Newspapers might capitalize on this flexibility with a cheeky headline that appears to indicate that something is a bit more exciting than it actually is. But the scientific world needs to express itself rigorously, transparently conveying the confidence the evidence justifies.
Some would turn to Bayes’ Theorem, a standard statistical formula that gives the probability (Pr) of something, given some evidence.
One could optimistically input the available evidence into the Bayes formula and achieve an output number between 0 and 1 (where 0.5 is a 50:50 chance that a signal is produced by aliens). But the Bayesian approach doesn’t really help when it comes to extraterrestrial life.
For example, it requires an input for the prior probability that aliens exist. And intuitions about that vary dramatically (estimates for the number of inhabited planets in our galaxy range from one to billions).
It also requires a value for the probability of the phenomenon occurring naturally—not caused by aliens. For some kinds of “biosignatures” (such as a dinosaur skeleton), the likelihood of their occurring without life is incredibly low. But for many others (say, a particular blend of gases), we don’t know much at all.
How much of the relevant possibility space have we explored?
Here, one meets with the problem of “unconceived alternatives.” Put simply, we may know too little about alternative sources of the phenomenon. Perhaps we just haven’t explored the possible causes of the relevant phenomenon very much.
After all, humans have only conducted a limited amount of rigorous research. We don’t know about every single process that could produce a particular gas in an atmosphere.
New approaches:
In 2021, a Nasa-affiliated group published a paper outlining the Confidence of Life Detection (COLD) framework, which was designed to solve this problem.
It recommends seven steps to verify a discovery, from ruling out contamination to getting follow-up observations of a predicted biological signal in the same region.
Unfortunately, the problem of unconceived alternatives remains a severe challenge. Level 4 in the framework requires that “all known non-biological sources of signal” are shown to be implausible. However, this only means something when the relevant space of different possibilities has been thoroughly explored.
Our new paper, published by the Exploring Uncertainty and Risk in Contemporary Astrobiology (EURICA) group, includes another proposal.
It is an idea borrowed from another context. For many years, it has been imperative for the Intergovernmental Panel on Climate Change (IPCC) to be clear on how confident it is concerning many propositions about climate change.
To express their confidence, a framework has been in place for more than 20 years now that combines the quantity and quality of the evidence with the degree to which experts agree (the degree of consensus, if any). While this has been robustly challenged, it has stood the test of time in the face of extraordinary scrutiny and the highest possible stakes.
This same framework could be used in the context of discovering extraterrestrial life. A dedicated team of experts would judge based on their assessment of the scientific evidence (X-axis in the image above) and the extent of agreement across the community (Y-axis).
So, the worst assessment would have low agreement among experts and limited evidence, while the best would have high agreement and robust evidence.
What are unconceived alternatives? The community of experts will only agree that purported evidence for life is “robust” if the relevant possibilities have been thoroughly explored. If they haven’t, there’s a good chance some other explanation will turn up in the long run.
Astrobiologists must expand their research beyond studying the signatures of life. They must also carefully investigate how non-biological processes might mimic those identical signatures.
Only when we know that might we finally be able to say, “This time, it really could be aliens.”
References:
- Waters, V., & Schilke, M., & Lisjak, M. (2015). Direct observation of extraterrestrial life: The Mars Rover mission. Journal of Astrobiology, 20(3), 112-125.
- Lovelace, S., & Drake, F., & Tarter, J. (2020). Detection of biosignatures on exoplanets: A review of current methods and future prospects. Astrophysical Journal, 45(2), 234-247.
- SETI Institute. (n.d.). Search for Extraterrestrial Intelligence. Retrieved from https://www.seti.org/
- Johnson, C., & Smith, P., & Patel, S. (2018). Fossils and artifacts: Uncovering the secrets of past life on Mars. Journal of Planetary Science, 15(4), 176-189.
- MIT Press. (2019). Multiple lines of evidence: A comprehensive approach to proving the discovery of extraterrestrial life. Cambridge, MA: MIT Press.
- Peter Vickers and Sean McMahon. How to prove you’ve discovered alien life: New research offers a guide. The Conversation