The discovery of an Earth-like exoplanet in the habitable zone is one of the most important achievements in modern astronomy. With advances in space telescope technology such as TESS (Transiting Exoplanet Survey Satellite) and Kepler, scientists are increasingly able to detect new worlds that have the potential to support life. The habitable zone is the area around a star where the temperature allows for the existence of liquid water which is vital for life. One exoplanet that is attracting attention is Proxima Centauri b, which is located in the Proxima Centauri star system, the closest star to Earth. Proxima Centauri b is about 4.24 light years from Earth and has a mass about 1.17 times that of Earth, making it a strong candidate for supporting life. This discovery provides new hope for space exploration. Not only Proxima Centauri b, other planets such as Kepler-186f and TRAPPIST-1e have also shown characteristics similar to Earth. Kepler-186f is nearly the size of Earth and is located in the habitable zone around its star, which is key to finding exoplanets with the potential for life. Detecting Earth-like exoplanets involves various techniques, such as transit and radial velocity methods. The transit method, for example, measures the decrease in a star’s brightness as a planet passes in front of its star. Radial velocity, on the other hand, detects changes in a star’s spectrum due to a planet’s gravitational pull. In addition, atmospheric variations on exoplanets are important for assessing the potential for the existence of life. Observing atmospheric spectra allows scientists to determine the composition of gases, such as oxygen, methane, and carbon dioxide, that may indicate signs of life. The discovery of exoplanets in the habitable zone also opens up opportunities for further exploration missions. Missions such as Mars 2020 and the Perseverance Rover aim to search for traces of past life on Mars, while search missions for Jupiter and the moon Europa focus on potentially fertile environments beneath the icy surface. Further research will help better understand the characteristics of these planets. The discovery of this exoplanet also deepens our understanding of the limits of life beyond Earth. Scientists are now trying to identify what makes planets habitable and how life can thrive in extreme conditions. As technology continues to develop, the ability to explore exoplanets and search for signs of life will only increase. With all these discoveries, challenges remain. Although many exoplanets have been discovered, only a few can be reached with current technology. However, this search inspired a new generation of scientists and policymakers to explore space and seek answers to humanity’s fundamental question, namely whether we are alone in the universe. This is not only a quest to discover new life, but also to understand our place in the wider cosmos.