In recent decades, astronomers have discovered many planets that they believe are “Earth-like” in nature, meaning that they appear to be terrestrial (i.e. rocky) and orbit their stars at the right distance to support the existence of liquid water on their surfaces. Unfortunately, recent research has indicated that many of these planets may in fact be “water worlds“, where water makes up a significant proportion of the planet’s mass.
Proxima b is the subject of a lot interest these days. And why not? As the closest extrasolar planet to our Solar System, it is the best shot we have at studying exoplanets up close in the near future. However, a recent study from the University of Marseilles indicated that, contrary to what many hoped, the planet may be a “water world” – i.e. a planet where up to half of its mass consists of water.