Detecting Extra-Terrestrial Communications

The debate of whether life exists outside earth has lingered for years. In 1976, the first effort toward exploring the possibilities of life outside earth began when NASA sent two space probes (Viking 1 and 2) to Mars. The probes collected samples of the soil, microbes and other nutrients. They thereafter monitored the bioactivities of these samples for a period of time. 

The first result from Walking 1 looked interesting. It revealed that radiolabeled gasses were emitted from the samples when treated. While this was an indication of biology on Mars, the results from other experiments did not corroborate that. 

The other experiments from the Vikings' expedition showed only a sparing amount of organic molecules such as chloro- and dichloromethane. The absence of complex organic molecules was sufficient to disprove the initial results of possible biology on Mars. Supplementary experiments on the samples yielded no compelling results as well. 

After many years of back and forth, the scientific community concluded that the observations from the experiment were from nonliving processes and not an indication of extraterrestrial life. But one should not be quick to disregard non-living processes in the search for life outside earth. After all, primitive life can emerge from nonliving matter. This is termed abiogenesis.

About Abiogenesis

Abiogenesis is the notion that living things can stem from non-living things. Before the 15th century, it was popularly believed that a few living things could be born from inanimate objects. Mice appeared in stored grains from nowhere, maggots appeared in spoiled meats, and frogs were found on the bank of River Nile during the annual flooding. However, in 1668, Francesco Redi carried out research that disproved abiogenesis. He attempted to understand how maggots were formed in spoiled meat.

In his experiment, he put meat in 3 separate containers and left them for a while. Some of the containers were completely sealed, while others were left open. Francesco observed that the containers of meat left open invited flies, whose eggs produced maggots. In the containers where the flies could not penetrate, no maggot appeared on the meat. He concluded that maggots did not come from the meat but from the eggs laid by flies on the meat. This is one of the many experiments that disproved abiogenesis.

Source: Memorial University

In spite of all these, the idea of abiogenesis has been tweaked to have a slightly different meaning. Looking holistically, it is believed that primitive life on earth originated through abiogenesis. The earth is said to be about 4.5 billion years, whereas life on earth began 3.5 billion years ago. Primitive life was a gradual process of RNA-based biomolecules transforming non-living matter. RNA intrinsically had genetic and catalytic properties - making living things adapt to their environment and become more sophisticated as time progressed. They are the major reason life was formed on earth 1 billion years after its existence.

But where does RNA come from? NASA had reported that RNA and DNA must have come from asteroids from outer space, in the form of meteorites. They propagated on earth and with other biomolecules such as amino acids, carbohydrates and lipids, led to the creation of life.

With this revelation, one may then argue that if life came about from nonlife on earth, how are we be certain it cannot happen on other planets? In our interview with David S. Spiegel on the Data Skeptic show, David called abiogenesis a probable process. He further discussed the probability of abiogenesis using the Bayesian statistical framework.

Fast Radio Burst - An Occurrence that Suggests Extraterrestrial Existence

Fast radio bursts are a sudden spike of radio frequencies from sources far away from our galaxies. It is one mystery scientists are trying to puzzle. Some questions that beg for answers include:

• Where are they coming from?

• When do they occur?

• Are people transmitting signals to us?

Succinctly, the source of fast radio bursts (or FRBs) is unclear. But by observing radio bursts between September 2018 to October 2019, scientists have made some progress in observing this strange phenomenon. Within that space of time, they discovered 28 bursts, with one occurring in a repetitive pattern. 

The repetitive pattern makes us suggest that it is not a random occurrence. Some scientists believe that they could be from orbiting celestial bodies such as black holes and stars. A research by Manasvi Lingam and Abraham Loeb revealed that these bursts were from transmitters. However, since they come from different galaxies scattered apart, it is believed that aliens could not have attained that high level of civilization that the only sign of them is through sudden energy surge. So the idea of FRBs coming from aliens was ruled out. The paper concludes that FRBs are more speculative than astronomical.

The search for extraterrestrial intelligence (SETI) has built radio telescopes and optical instruments to detect signals from outside the earth. In an interview with Gerry Zhang, an affiliate of Berkeley SETI Research Center, Gerry revealed that SETI aims to investigate the possibility of extraterrestrial transmitting interstellar signals. He explained why radio signals were the choice mode of communication and spoke about a deep learning model that detects FRBs.

How about UFOs?

Unidentified flying objects (UFOs) are another phenomenon that suggests that aliens exist. But just as the name suggests, they are still unidentified. In 2017, US pilots reported that they saw strange objects in the sky. Their observation was received by the government and probed. 

The final report of the investigation by the Pentagon, however, stated that there was no tangible explanation for the flying objects. Perhaps, they were physical objects created by China or Russia.

UFOs can safely be classified as conspiracy theories. This happens when people do not completely understand a concept but tend to hold certain unproven beliefs. In our interview with Mick West, he discussed how conspiracy theories are propagated and spread using social media. He also highlighted steps that can be taken to bring people out of the rabbit hole. Mick recently put out a video that explained how the 'Gimbal' UFO is fictitious.

How to ascertain life outside earth?

Amidst these strange occurrences, the crux of the matter is to identify whether life exists outside Earth. While at that, it is important to clearly define what life is exactly. Apparently, the presence of a biochemical in another planet, however active, does not sufficiently conclude that life exists there. 

NASA researchers developed a framework to determine the conditions for existential life. It is called the ladder of life detection. Here are the features to conclusively say a living object exists. 

1. Darwinian evolution

2. Growth and reproduction

3. Metabolism

4. Functional molecules and structures

5. Potential biomolecule components

6. Potential metabolic by-products

7. Biofabrics

The gravity of each feature is progressive. However, it is important to have all features on a given planet to conclude the existence of life.

Wrapping up

With strange occurrences we observe, it is difficult to admit that there are no extraterrestrial beings. However, there is no scientific evidence to prove the existence of aliens. It is safe to say, we are alone in the universe. At least, for now!