The three nearest Sun-like stars and their exoplanets

Star system: Alpha Centauri | Distance from the Sun: 4.4 light years

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The three nearest Sun-like stars and their exoplanets

Star system: Alpha Centauri | Distance from the Sun: 4.4 light years

The closest Sun-like stars to the Solar System are Alpha Centauri A, Tau Ceti, and 82 G. Eridani. All three are G-type main-sequence stars, broadly similar to the Sun, although they differ in mass, temperature, age, and planetary systems.


Alpha Centauri A — 4.37 light-years
Alpha Centauri A is the closest Sun-like star to the Solar System. It is a G2V star with about 1.1 times the mass of the Sun. Its surface temperature is approximately 5,753 K, very close to the Sun's temperature.

Alpha Centauri A is part of the three-star Alpha Centauri system, together with Alpha Centauri B and the red dwarf Proxima Centauri.

Stellar Catalog lists three exoplanets in the Alpha Centauri system: Proxima Centauri d, Proxima Centauri b, and the unconfirmed Proxima Centauri c. These planets orbit Proxima Centauri, not Alpha Centauri A. Proxima b has a mass of about 1.2 Earth masses and orbits its star every 11.2 days.

- Spectral class: G2V
- Mass: 1.1 M☉
- Distance: 4.37 light-years
- Exoplanets in the system: Proxima Centauri d, b, and unconfirmed c


Tau Ceti — 11.9 light-years
Tau Ceti is a single G8V star located about 11.9 light-years from the Sun. With approximately 0.69 solar masses, it is smaller and cooler than the Sun, but it belongs to the same broad G-type stellar family.

Stellar Catalog lists six planetary objects in the Tau Ceti system: Tau Ceti b, c, g, h, e, and f. Tau Ceti b and c are marked as unconfirmed in the Stellar Catalog data. The system also contains a distant asteroid belt at approximately 10 AU.

- Spectral class: G8V
- Mass: 0.69 M☉
- Distance: 11.9 light-years
- Exoplanets: Tau Ceti b, c, g, h, e, and f


82 G. Eridani — 19.7 light-years
82 G. Eridani, also known as HD 20794, is a G6V star about 19.7 light-years from Earth. It has approximately 0.70 solar masses and a surface temperature of about 5,401 K. The star is older than the Sun, with Stellar Catalog estimating its age at about 8 billion years.

The system contains several known or candidate planets. Stellar Catalog lists 82 G. Eridani b, c, and d, together with the unconfirmed g, e, and f. Planet d orbits at about 1.35 AU, while the unconfirmed planet f is listed at approximately 0.88 AU within the star's habitable zone.

- Spectral class: G6V
- Mass: 0.70 M☉
- Distance: 19.7 light-years
- Exoplanets: 82 G. Eridani b, c, d, and unconfirmed g, e, and f


A nearby group of Sun-like planetary systems
These three stars demonstrate why nearby G-type stars are important targets for exoplanet research. Alpha Centauri A is remarkably similar to the Sun in spectral class and temperature, while Tau Ceti and 82 G. Eridani are somewhat cooler and less massive. All three systems provide nearby examples of how planetary systems can form and evolve around stars broadly similar to our own.

Data and distances in this article are based on the Stellar Catalog database. Stellar Catalog combines data from sources including Gaia, SIMBAD, research publications, and exoplanet databases; some stellar and planetary values are estimates, and some planetary detections are explicitly marked as unconfirmed.

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