Has life been found on another planet?

Ever since I was a kid I’ve been interested in science.  While this may come as a shocker to those who know me as an air dispersion modeler (insert sarcasm here), my first interest in science wasn’t in air pollution, it was space.  I recall having a book on planets when I was young (there were nine then!) and I loved learning about space flight.  I think it’s in my genes—I was born at Cape Canaveral, as my dad was working on the Apollo missions at the time.

So today I’m going to deviate a bit from my usual subject of air quality and venture off-world…124 light years off-world, or 700,000,000,000,000 (that’s 700 trillion) miles to be more precise. 

Planet K2-18b (if you ask me, Star Trek was much better at naming planets) has become a most intriguing planet over the past few years.  In 2019 it became the first exoplanet found to have water vapor in its atmosphere.  In 2023 the James Webb Space Telescope (JWST) found evidence of carbon dioxide and methane—often associated with biological processes on Earth.  And most recently the JWST found that K2-18b has the chemical signature of at least one of two molecules that, here on Earth, are only produced by marine phytoplankton and bacteria—dimethyl sulphide and dimethyl disulphide.  In fact, the amount of this gas in K2-18b’s atmosphere is thousands of times higher than here on Earth.

When JWST was put into service a few years ago it was, in my opinion, one of the seminal moments in the history of science—because, for the first time, we had a legitimate shot at finding life on other planets.  JWST is by far the most powerful telescope ever built and was placed far beyond the moon, about one million miles from Earth—so it has the best view of the universe we’ve ever had.  In addition to being able to see back to nearly the beginning of time, it can analyze the chemical composition of a planet’s atmosphere.

Because K2-18b is much larger than Earth (its radius is about 2.5 times that of Earth’s, and it’s about 8.6 times the mass), it likely does not have a solid surface.  But there’s definitely a chance that there could be some sort of life in its oceans, which could be liquid water.  The Cambridge team that has made this latest discovery has said it should take about one to two years to confirm their findings.  I for one can’t wait to hear their conclusions!