Thirty years after the discovery of the first exoplanet, astronomers have detected more than 7,000 of them in our galaxy. But there are still billions more to be discovered. At the same time, exoplanetologists have begun to take an interest in their characteristics,

An exoplanet is a planet outside our solar system that usually orbits a star in our galaxy. More than 7,000 have been found in the Milky Way since the first confirmed discovery in the 1990s, and "billions more remain to be discovered", said Tech Explorist.

Astronomers who identified HD 20794 d say its proximity to its host star and orbital pattern suggest it could hold water.