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Exoplanets
Beginner
Planets orbiting other stars found via transit and radial velocity.
Planets around other stars, found by transits (dip in brightness), radial velocity (stellar wobble), microlensing and direct imaging. Over 5000 are known.
Kepler found thousands.
Many are 'hot Jupiters'.
In more detail
Exoplanets are planets orbiting stars other than the Sun. Thousands have been discovered, and they vary from hot Jupiters to rocky worlds.
Real-world uses
- Exoplanet surveys search for planets that could support life.
- Telescopes such as Kepler and TESS find exoplanets using transits.
- Astronomers find exoplanets by watching the dimming of a star as a planet passes in front of it.
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Frequently asked questions
How many exoplanets are known?
Thousands have been confirmed by 2026.
How are they found?
Mainly by transit photometry and radial velocity measurements.
How many exoplanets are known?
Thousands have been confirmed, and new discoveries are made regularly by telescopes such as Kepler and TESS.
Related topics in Particle Physics & Cosmology
Dark energy · Critical density · Fate of the universe · Habitable zone · Astronomical distances · Parallax and standard candles