120 Light-Years Away, Astronomers Find Most Promising Signs of Alien Life Ever Detected

by

For many millennia, humans have gazed into the night sky, pondering whether other life forms exist beyond our planet. Today, it seems that astronomers could soon provide a definitive answer to this question.

Up to this point, over 5,000 exoplanets have been identified across the universe, yet none have displayed clear indications of hosting life as we know it. Regardless of where we’ve focused our search, we haven’t stumbled upon any trace of Harry Vanderspeigle (or any Resident Alien characters for that matter). However, on one particular exoplanet, astronomers have now discovered the strongest signs to date suggesting the presence of extraterrestrial life.

For More on Exoplanets

Water Vapor Found in the Atmosphere of a Cool, Neptune-like Exoplanet

The Largest Earth-Based Telescope Could Detect Potential Life Signs on Other Planets Within Hours

Top Picks for Habitable Exoplanets: The Most Suitable Ones Within 25 Light-Years Away

Exoplanet K2-18b keeps teasing signs of alien Life 120 light-years away

In the year 2015, astronomers identified a planet named K2-18b that revolves around a red dwarf star situated approximately 120 light-years away from us. From our vantage point, the planet orbits its star sideways, causing it to pass exactly in front of the star once during each orbit, making it visible to us. K2-18b takes about 33 days to complete one orbit around its star and maintains a distance of roughly 14 million miles from it.

K2-18b is situated at a distance that’s significantly less than Earth’s 93-million-mile orbit from the Sun, but because red dwarfs emit less light, it receives roughly the same amount of starlight as our planet does. This position within the star system makes K2-18b part of its habitable zone.

According to astronomer Phil Plait, when looking for possible habitats for life, K2-18b is certainly worth considering as an option.

From preliminary findings, scientists approximated K2-18b to be approximately 2.5 times Earth’s diameter and around 8 times its mass, with a surface gravity about 1.5 times that of our planet. These initial observations hinted at the potential presence of liquid water or ice on its surface, as well as an atmosphere. Intriguingly, in 2023, astronomers reported possible indications of biological signs on K2-18b.

Based on observations made with JWST’s built-in instruments, it appears we may be dealing with a Hycean planet – a celestial body that could contain either liquid water or ice, along with an atmosphere rich in hydrogen. Furthermore, these observations have provided us with additional insights about the planet’s atmospheric composition.

To understand what types of substances are present in a certain sample without physically examining it, we use a technique similar to observing an animal preserve from afar. Instead of entering the preserve, we shine different types of light (like plates filled with various foods) onto the sample and observe how the light interacts or is absorbed by each substance. If the light passes through unchanged, it suggests the sample may be devoid of certain elements. However, if a particular type of light (such as zebra meat to lions) is strongly affected, we can infer that specific substances are definitely present within the sample. This is how spectroscopy functions.

As an enthusiastic stargazer, I observe how the light from a celestial body, like a star, changes before, during, and after a planet passes in front of it. Normally, the star’s radiance (its ‘plates’) reaches me unaltered. But when a planet aligns with the star, some frequencies of the starlight are absorbed by molecules within the planet’s atmosphere. When I examine the starlight during transit, there are noticeable gaps in the spectrum (as if some ‘food’ has gone missing from the plates), and this allows me to deduce what components make up the planet’s atmosphere.

2023’s spectral analysis uncovered the presence of methane and carbon dioxide in K2-18b’s atmosphere. It also hinted at a faint, uncertain trace of dimethyl sulfide (DMS).

Astronomers have detected most promising signs of alien life ever on Exoplanet K2-18b

On our planet, Dimethyl Sulfide (DMS) is created solely by biological entities, primarily phytoplankton and certain bacteria. It’s a significant contributor to the “fishy” odor you might encounter when visiting beaches. Initially, astronomers observed DMS detection as intriguing yet uncertain.

Back in May 2024, a new study stirred some uncertainty about the findings, hinting that for DMS to be detectable with our current equipment, it should be present at concentrations no less than twenty times what we have on Earth. In the end, astronomers all around concurred: more information was crucial. Well, Now, let’s dive in and see what this new info reveals!

Scientists at Cambridge University’s Institute of Astronomy have recently provided further proof of finding DMS and other biomarkers on K2-18b. These findings, considered the strongest hints of extraterrestrial life yet discovered, were shared in a publication for The Astrophysical Journal Letters.

New measurements taken with a distinct tool have found either Dimethyl Sulfide (DMS) or its related compound, Dimethyl Disulfide (DMDS), on K2-18b, or a mix of the two. On Earth, these molecules are exclusively produced by living organisms. However, since such claims demand substantial proof, even the researchers acknowledge that they’re not completely certain that life exists on K2-18b.

As an enthusiast, I firmly believe in constantly questioning my own findings. It’s through repeated testing and verification that I can eventually gain the assurance I need in them. This is the essence of scientific exploration – a never-ending quest for certainty.

As a gamer exploring the cosmos, I’ll proceed to strengthen the confirmation of the presence of Dimethyl Sulfide (DMS) and/or Methyl Disulfide (MDS) in the atmosphere of K2-18b. Once we’ve positively identified these compounds, it’s time for us to delve into whether they can be naturally produced through non-living processes. Here’s an interesting twist: if our findings are verified, the levels of DMS/MDS in K2-18b could be thousands of times greater than on Earth!

Researchers speculate that a world entirely submerged in an oceanic expanse, teeming with organisms similar to phytoplankton, could potentially generate the observed signal. However, further investigation may uncover alternative explanations or possibly eliminate the signal altogether.

It’s possible that K2-18b could be the location where we discover extraterrestrial life for the first time outside of Earth, but this discovery would mark a significant milestone in astronomy, made possible by advanced observatories and tools. If life does exist out there, on K2-18b or elsewhere, our ability to locate it has never been greater than it is now.

In the future, we might reflect on this moment as when humanity got closer than ever before to understanding if the universe has other inhabitants, according to Madhusudhan. This could be a turning point where we gain the ability to answer the age-old question about life beyond Earth.

Read More

2025-04-17 21:32