On April 17 of this year, astronomers revealed that they had found the most prominent evidence yet of possible life on planet K2-18b in the Leo constellation. K2-18b is currently 124 light-years away and is an ocean, or hycean, planet. Earth is also a hycean planet, meaning that it has a vast ocean and an atmosphere rich in hydrogen gas. 

But what was the evidence found of suspected life? Junior Marley Parreco believes that the evidence “would be remains such as fossils or bones,” but this was not the case with K2-18b. Dimethyl sulfide and dimethyl disulfide are both considered chemical “biosignatures” since, on Earth and from what scientists understand, these two chemicals can only be released by living things. Usually, the living things producing these chemicals are microscopic marine algae called phytoplankton. 

When most people think of aliens, their thoughts usually go to the little green guys from old science fiction movies, but Junior Abigail Raikes says aliens are probably “not like the ones in the movies. They would be more like microbes such as bacteria!”  

This aligns with what theories of alien life would suggest as scientists learn more about how life can evolve on other planets. Although scientists say that they can’t be certain about the “evidence,” some do think that they will be able to confirm the signal in the next one to two years.