Photo by ArtHouse Studio

Over the years, we have been wondering if Earth is the only living planet in the universe or if extraterrestrial life forms exist.

In Bob Ticer’s The Alien Stranger, a sci-fi book with a unique story, a girl named Kayla meets an alien stranger who helps her with potential violence coming her way. It turns out that a hummingbird keeps on following her like a drone. She wonders how some of the potentially dangerous and harassing people know her name before they attack her. Fortunately, her connection to the alien stranger seemingly keeps her safe from harm.

The Fermi Paradox is a discrepancy that raises an argument whether life forms exist on other planets or we are alone in the universe. The lack of evidence of life forms made us question the probability of the existence of other planets that can support life as well. With this, astrobiologists try to find any evidence that suggests life on the other corners of the cosmos.

Fictional stories make use of the argumentative idea of the Fermi paradox to level up the suspense and horror. But do life forms really exist outside planet Earth? Here are pieces of controversial evidence of alien forms discovered over the years:

Chemical Signatures on Mars 

Living organisms metabolize different substances that yield chemical compounds. One of these substances is methane. In 1976, NASA’s Viking lander detected the presence of radioactive methane on the Martian soil.

Methane is one key indicator that life thrives in a particular area as it is the result of microbial activity on decomposing organic matter. However, the lander failed to provide evidence of life, so it was reported to have been a false positive result.

Meanwhile, in 2004, another discovery states that methane gas is evident in the Martian atmosphere, proving that microbes are present on the red planet. However, scientists have yet to prove this claim, as volcanism can also produce this greenhouse gas.

In 2005, another claim on the presence of formaldehyde has been proposed. Formaldehyde is a product of methane that undergoes oxidation in the presence of a catalyst. Nevertheless, scientists are yet to prove their ideas as there is a need for chemical measuring tools to be sent to Mars first.

Photo by Daniele Colucci

Extraterrestrial Signals

A radio telescope at Ohio State University detected a 37-second signal in August of 1977. The extraterrestrial frequency started the astronomers as the printout translated it to “Wow!” The radio signal was detected within the proximity of the constellation Sagittarius.

In 2003, a radio telescope in Puerto Rico detected unexplained extraterrestrial signals that have gradually disappeared, except for one. All three signals were from the areas between the Pisces and Aries constellations.

Photo by Pixabay

Fossils in a Meteorite

In 1984, a meteorite called ALH84001 was discovered in Antarctica. It is believed to be a piece of rock blasted off from Mars 15 million years ago. Scientists found traces of nanobacteria in the meteorite. These microfossils, however, could be meteorite crystals that looked like nanobacteria.

Photo by Beaumont Yun

The Origin of Sulphur Traces on Jupiter’s Europa 

One of Jupiter’s natural satellites, Europa, characterizes red streaks, which were suggested as microbial traces by NASA researchers in 2001. There have been proposals for a voyage to Jupiter’s Europa to find things out. Even though some of the exploration plans were canceled, Jupiter Icy Moons Explorer (JUICE) finally launched in April 2023. Another mission, Europa Clipper, is set to launch in October 2024.

Photo by NASA

So far, the alien life forms that have a strong presence in controversial pieces of evidence are microbes. Indeed, if astronomers prove the existence of life on other planets, should we be concerned of our own sake in our galaxy? Will the discovery open doors for more deep space exploration? Will we finally find answers to the Fermi Paradox?