As of now, astronomers have officially confirmed the existence of 8 planets within our Solar System. Beyond our cosmic neighborhood, thousands of exoplanets—planets orbiting stars outside our solar system—have also been discovered, expanding our understanding of planetary systems across the universe.
Planets in Our Solar System
Our Solar System comprises eight recognized planets, listed in order from the Sun:
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
These planets have been known for centuries, with their classifications and characteristics refined through centuries of observation and space missions. Historically, Pluto was considered the ninth planet until 2006, when the International Astronomical Union reclassified it as a dwarf planet due to its size and orbital characteristics.
Discovering Exoplanets
While our Solar System’s planets are well-documented, the universe contains countless other planetary systems. Since the first confirmed detection of an exoplanet in 1992, astronomers have identified over 5,300 exoplanets as of October 2023, with thousands more candidates awaiting confirmation. These discoveries have been made primarily through space-based telescopes such as Kepler, TESS, and CHEOPS, which detect planets by observing the dimming of stars as planets transit in front of them or by measuring stellar wobbles caused by gravitational pull.
Exoplanets vary widely in size, composition, and orbit. They include gas giants larger than Jupiter, Earth-like rocky planets, and even potentially habitable worlds within the so-called
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