Ocean Planet
An "ocean planet" typically refers to a type of exoplanet that is covered by a global ocean of water, potentially with no or only a small rocky core beneath. The concept of ocean planets is intriguing because they could potentially support unique forms of life in their subsurface oceans, even in the absence of a solid surface.
Various methods were being used to detect and study exoplanets, including the transit method (observing a planet as it passes in front of its host star, causing a temporary dimming of the star's light) and the radial velocity method (detecting the gravitational wobble of a star caused by the presence of an orbiting planet). These methods allowed scientists to infer properties of exoplanets, such as their size, orbital period, and sometimes even their composition.