Does Planet K2-18b Show Signs of Life?

     Exoplanets, or extrasolar planets, are planets that are outside our solar system and so therefore orbit stars other than our sun. The quest to discover these worlds has added to our understanding of the universe, challenging our preconceived notions of planetary systems. It wasn't until the 1990s that the first confirmed exoplanets were discovered, expanding the field of astronomy and giving more credence to the notion that we are not alone in the world. Since then, the search for exoplanets has become a central focus of astrophysical research, employing advanced technology and innovative methods to peer deeper into space than ever before.

What is K2-18b?

    Among the thousands of exoplanets discovered so far, K2-18b stands out as one of the most intriguing. Located in the constellation of Leo, approximately 124 light-years from Earth, K2-18b orbits within the habitable zone of its star, K2-18. This zone, often referred to as the "Goldilocks zone," is the region around a star where conditions might be just right for liquid water to exist on a planet's surface - a crucial factor for the possibility of life as we know it.

    K2-18b is categorized as a super-Earth, which is a type of exoplanet that has a mass higher than Earth's but significantly lower than that of the solar system's gas giants like Uranus and Neptune. This classification hints at the planet's potential for having a solid surface, though the exact nature of its composition remains a subject of research.

The Discovery of K2-18b

    The discovery of K2-18b was made possible by the Kepler Space Telescope, a spacecraft launched by NASA in 2009 to discover Earth-sized planets orbiting other stars. Utilizing the transit method, whereby the telescope detects the slight dimming of a star's light as a planet passes in front of it, Kepler identified K2-18b in 2015. This discovery marked the beginning of a new chapter in the study of exoplanets, highlighting the potential for finding Earth-like worlds in the habitable zones of other stars.

Characteristics of K2-18b

    K2-18b exhibits several fascinating characteristics that set it apart from other known exoplanets. Its location within the habitable zone suggests that it could possess conditions favorable for the presence of liquid water. Furthermore, data from subsequent observations have indicated the presence of water vapor in the planet's atmosphere - a significant finding that raises the possibility of K2-18b being more habitable than previously thought.

    It’s believed that K2-18b has a gas, dimethyl sulfide (DMS), which has only one source on earth and that’s living beings, but it mainly comes from phytoplankton in the earths oceans. An article in wionews.com quoted Dr Nikku Madhusudhan, an astrophysicist from the University of Cambridge that was leading the study, recalled when his analysis showed that there was over a 50% confidence level that DMS was present on K2-18b he stated, "It was a real shock, I had sleepless nights for a week. That week, I didn't even muster the courage to break it to my team." The article went on to say we will have to wait four to six months for the results while the "theoretical work" on the source of DMS continues. Madhusudhan said, "If we do detect DMS [on K2-18b] it does put it basically at the top for potential signs of habitability."

As the search continues for proof that other habitable planets exist in the universe skeptics will continue to say that the planet is 'x' number of light-years away from earth so even if life is or was there it’s not possible for intelligent life to travel here or communicate with us. But as I say in my book, Aliens Are With Us, scientists have theorized about the ability to exceed the speed of light, and that if it were possible, it would imply time travel. So, to me it is possible for aliens to travel here or communicate with us, just not with our current technical knowledge and capabilities but the aliens that visit us are far, far more advanced than we are so we can’t fathom what is possible for them.