We’ve discovered our best candidate for a plan B. 

Exoplanet K2-18b can be located 110 light years outside our solar system, and is touted by scientists to present the chance to either discover existing alien life, or establish a new beginning for humanity among the stars. Astronomers found this planet to be within the habitable zone of a star and  have confirmed the presence of water vapor that could potentially support life—a combination that has yet to have been found outside Earth. 

With its earlier discovery in 2015, the exoplanet’s distance from its adjacent star has always been of noteworthy for scientists, as K2-18b allows for the possibility of hosting lifeforms and liquid water. Thorough data collection using the Hubble Space Telescope, Angelos Tsiaras and her team were led to a promising conclusion: water vapor was indeed present and it was discovered in clouds around the planet’s atmosphere.

It was on September 11 when these findings were published and the discovery was surrounded by great media coverage. K2-18b has been the focal point of various articles and social media posts alike. However, there are still glaring issues that are being downplayed, if not ignored by some news outlets. 

K2-18b likely does not have a solid surface, similar to the planet Neptune. The planet’s atmosphere is also likely to contain a significant concentration of helium and hydrogen, which are not found in similar concentrations on Earth. Until more advanced telescopes and spacecraft are used by space agencies across the globe, we may never be sure about the habitability of K2-18b. In essence, our second best option for habitability is seemingly uninhabitable. The discovery’s biggest contribution is not necessarily the discovery of a second Earth, however, but a glimpse of what other planets could be, hence why astronomers continue to look around K2-18b’s orbit. 

With discoveries like these, the promise of finding another Earth grows larger and larger – but at this point, all we have is promise. 

The study: https://www.nature.com/articles/s41550-019-0878-9