There are several methods used to detect exoplanets, including the transit method, the radial velocity method, direct imaging, and microlensing.

The transit method involves monitoring a star for a decrease in brightness, which occurs when a planet transits, or passes in front of it. This technique allows scientists to determine the planet’s size and orbital period; however, it does not provide information about the planet’s mass or composition.

The radial velocity method measures the star’s wobble caused by the gravitational pull of an orbiting planet. This wobble can be detected through variations in the star’s spectrum. This method is effective for determining the planet’s mass and orbital period, but it does not yield data on the planet’s size or composition.

Direct imaging entails capturing images of the exoplanet itself. This approach is particularly challenging due to the overwhelming brightness of the parent star. Nonetheless, direct imaging can provide insights into the planet’s size, composition, and atmospheric characteristics.

Microlensing relies on the gravitational lensing effect produced by a star, which bends and magnifies the light from a more distant background star. This phenomenon can indicate the presence of a planet orbiting the lensing star. Microlensing is especially useful for detecting planets that are located far from their host stars or are situated outside the observer’s line of sight.

Each detection method has its own advantages and limitations, and researchers often employ a combination of these techniques to verify the existence and properties of exoplanets. The study of exoplanets has significantly enhanced our understanding of the universe and remains an exciting field of research.