Which method is commonly used to detect exoplanets?

The transit method is widely recognized as one of the most effective techniques for detecting exoplanets. This method works by monitoring the brightness of a star over time. When a planet passes in front of its host star, it blocks a fraction of the star's light, resulting in a temporary dimming that can be measured from Earth or space-based telescopes.

This dimming occurs at regular intervals, corresponding to the orbit of the planet. By analyzing the light curve — which is a graph of brightness versus time — astronomers can determine several key characteristics of the planet, such as its size, orbital period, and distance from the star. The reliability of this method has been demonstrated through missions such as NASA's Kepler, which successfully identified thousands of exoplanets using this technique, making it a cornerstone of exoplanet research.

While the other methods mentioned, like the Doppler effect and timing variation, are indeed useful in the study of exoplanets, the transit method stands out for its straightforward approach and the vast amount of data it has provided in recent years. Gravitational lensing can detect exoplanets but is less common and subject to specific conditions. Therefore, the transit method is the most prominent and widely adopted technique for ex