The Sun's Neighbors: Top 50 Closest Stars to Our System

Scientific Summary

This article presents a list of the closest stars to the Sun, located within 25 light-years. It details their main characteristics: spectral type (from G2V for α Centauri A to K7V for Gliese 673), apparent and absolute magnitudes, and distance in light-years. Notable celestial bodies include Proxima Centauri (4.24 ly), the closest star, the Alpha Centauri binary system (4.39 ly), Sirius (8.58 ly), the brightest star in the sky, and ε Eridani (10.50 ly), known for its planetary system. The article also discusses the concept of the Hill sphere and the zone of gravitational influence between neighboring stellar systems.

What are the closest stars to the Sun and what are their characteristics?

Our Solar System is not isolated in the vastness of the Milky Way. A few light-years away lie dozens of stars, neighbors that offer a privileged laboratory for studying stellar and planetary systems. The closest star is Proxima Centauri, a red dwarf located only 4.24 light-years away, which hosts at least one exoplanet in the habitable zone, Proxima Centauri b. Next is the Alpha Centauri binary system (4.39 ly), composed of two stars: α Centauri A (similar to the Sun, type G2V) and α Centauri B (type K1V, slightly cooler). Further out, we find Barnard's Star (5.96 ly), famous for its exceptional proper motion, and Wolf 359 (7.78 ly), a very active red dwarf. The article also lists bright stars like Sirius (8.58 ly), a binary system composed of a white dwarf and an A1V type star, and ε Eridani (10.50 ly), a K2V type star surrounded by a debris disk and at least one exoplanet. The complete list, derived from the Hipparcos catalog, includes stars of various spectral types, from red dwarfs to yellow stars, and specifies their apparent and absolute magnitudes, offering a comprehensive view of our stellar neighborhood.

The Sun's Zone of Influence

The Hill Sphere: A Gravitational Boundary

Space is immense, but the space between the gravitational zones of the roughly 100 billion stars in our Milky Way is relatively small. The Sun and the Alpha Centauri system are not gravitationally bound to each other; they are not in mutual orbit. Nevertheless, we can estimate, by approximation, a boundary of influence between the two systems by applying the Hill sphere formula to their current separation (about 4.24 light-years) and their respective masses. This calculation places the radius of the Hill sphere of the Alpha Centauri system at about 2.28 light-years, and places the limit of our Solar System's gravitational influence at about 1.96 light-years. A celestial object (a brown dwarf or a rogue exoplanet) could therefore station near this boundary, between the two systems, without being permanently captured by either.

The Sun's Neighboring Stars

Our star is part of the Milky Way, a galaxy that contains several hundred billion stars. Among them, some are particularly close to us. These neighboring stars offer a unique opportunity to study stellar and planetary systems outside our own Solar System. Here is a short list of the closest stars to the Sun and their main characteristics.

The Closest Stars to the Sun

After Proxima Centauri (4.24 light-years), the closest star to the Sun, come the Alpha Centauri A and B pair (4.37 ly), then Barnard's Star (5.96 ly), Wolf 359 (7.86 ly), etc. Most are red dwarfs, small and cool, with the notable exceptions of Sirius, a binary system hosting the brightest star in the night sky, and Epsilon Eridani, a K-type star surrounded by a debris disk. Several of these neighbors host confirmed exoplanets: Proxima Centauri b, the four rocky planets of Barnard's Star (b, c, d, e, confirmed in 2024-2025), and at least one planet around Epsilon Eridani.

Table of Stars Close to the Sun

Top 50 Closest Stars to Us
Rank	Common Name	Astronomical Name	Apparent Magnitude	Absolute Magnitude	Distance (light-years)	Spectral Type
1	Sun	Sun	-26.74	4.80	0	G2V
2	Alpha Centauri A	α Cen A	0.01	4.34	4.39	G2V
3	Alpha Centauri B	α Cen B	1.34	5.70	4.39	K1V
4	Sirius	α CMa	-1.46	1.42	8.58	A1V
5	Epsilon Eridani	ε Eri	3.72	6.18	10.50	K2V
6	61 Cygni A	61 Cyg A	5.20	7.49	11.40	K5.0V
7	61 Cygni B	61 Cyg B	6.05	8.31	11.40	K7.0V
8	Procyon A	α CMi A	0.34	2.65	11.50	F5IV-V
9	Epsilon Indi	ε Ind	4.69	6.89	11.80	K5Ve
10	Tau Ceti	τ Cet	3.49	5.68	11.90	G8Vp
11	Groombridge 1618	Groombridge 1618	6.60	8.16	15.90	K7.0V
12	40 Eridani A	ο² Eri A	4.43	5.92	16.50	K1Ve
13	70 Ophiuchi A	70 Oph A	4.24	5.71	16.60	K1Ve
14	70 Ophiuchi B	70 Oph B	6.01	7.48	16.60	K5Ve
15	Altair	α Aql	0.76	2.20	16.70	A7IV-V
16	Sigma Draconis	σ Dra	4.67	5.87	18.80	K0V
17	Gliese 570	Gliese 570	5.72	6.86	19.00	K5Ve
18	Eta Cassiopeiae	η Cas	3.46	4.59	19.40	G3V
19	36 Ophiuchi A	36 Oph A	5.07	6.18	19.50	K1Ve
20	36 Ophiuchi B	36 Oph B	5.11	6.22	19.50	K1Ve
21	36 Ophiuchi C	36 Oph C	6.33	7.45	19.50	K5Ve
22	HR 7703	HR 7703	5.32	6.41	19.60	K3V
23	82 Eridani	82 Eri	4.26	5.35	19.80	G8V
24	Delta Pavonis	δ Pav	3.55	4.62	19.90	G7V
25	Gliese 892	Gliese 892	5.57	6.50	21.30	K3V
26	Xi Bootis A	ξ Boo A	4.72	5.59	21.90	G8Ve
27	Xi Bootis B	ξ Boo B	6.97	7.84	21.90	K4Ve
28	Gliese 667 A	Gliese 667 A	6.29	7.07	22.70	K3V
29	Gliese 667 B	Gliese 667 B	7.24	8.02	22.70	K5V
30	HR 753 A	HR 753 A	5.79	6.50	23.50	K3V
31	Gliese 33	Gliese 33	5.74	6.38	24.30	K2V
32	Beta Hydri	β Hyi	2.82	3.45	24.40	G2IV
33	107 Piscium	107 Psc	5.24	5.87	24.40	K1V
34	Mu Cassiopeiae A	μ Cas A	5.17	5.78	24.60	G5VI
35	TW Piscis Austrini	TW PsA	6.48	7.07	24.90	K5Ve
36	Fomalhaut	α PsA	1.17	1.74	25.10	A3V
37	Gliese 673	Gliese 673	7.54	8.10	25.20	K7V
38	Gliese 701	Gliese 701	9.90	10.46	25.24	M1V
39	Tabit	π³ Ori	3.16	3.63	26.32	F6V
40	Gliese 686	Gliese 686	9.58	10.02	26.61	M1V
41	p Eridani A	p Eri A	5.82	6.25	26.73	K2V
42	Gliese 884	Gliese 884	7.88	8.30	26.85	K7Vk
43	Chi Draconis A	χ Dra A	3.68	4.08	27.17	F7V
44	Mu Herculis Aa	μ Her Aa	3.42	3.81	27.20	G5IV
45	Chara	β CVn	4.24	4.60	27.63	G0V
46	61 Virginis	61 Vir	4.74	5.08	27.84	G7V
47	Zeta Tucanae	ζ Tuc	4.23	4.56	28.07	F9.5V
48	Chi¹ Orionis A	χ¹ Ori A	4.39	4.70	28.26	G0V
49	5 G. Capricorni	HD 192310	5.73	6.00	28.74	K2+V
50	Groombridge 1830	Groombridge 1830	6.42	6.61	29.91	G8VIp

N.B.:
The magnitude scale is logarithmic and inverted; for example, a star of magnitude 5 is 2.5 times fainter than a star of magnitude 6. Absolute magnitudes for ranks 38 to 50 were calculated from apparent magnitude and distance (standard formula M = m − 5·log₁₀(d) + 5, with d in parsecs), in the absence of directly published values for these systems in the consulted catalogs. Data for ranks 1 to 37 come from trigonometric parallax catalogs (Hipparcos, Gaia revisions).

References

FAQ: Everything you need to know about stars close to the Sun

What is the closest star to the Sun and why is it so hard to observe?

The closest star to the Sun is Proxima Centauri, located about 4.24 light-years away. It is a red dwarf of spectral type M5.5V, meaning it is much smaller, cooler, and less luminous than our Sun. Its apparent magnitude is 11.05, making it invisible to the naked eye: a telescope is needed to observe it. It is part of the Alpha Centauri triple system, orbiting the two main stars at a distance of about 0.2 light-years. In 2016, astronomers discovered Proxima Centauri b, an Earth-mass exoplanet located in the habitable zone of the star, making it a prime target in the search for extraterrestrial life.

Why is Alpha Centauri such a heavily studied stellar system?

The Alpha Centauri system is the closest stellar system to ours, at 4.37 light-years. It is composed of three stars: Alpha Centauri A (type G2V, similar to the Sun), Alpha Centauri B (type K1V, slightly cooler), and Proxima Centauri (type M5.5V). The two main stars form a binary system whose orbit is well known, with a period of 79.9 years. Their proximity and similarity to the Sun make them ideal targets for exoplanet research and studying the formation of planetary systems. Furthermore, Alpha Centauri A is the brightest star in the constellation Centaurus and the third brightest star in the sky (apparent magnitude -0.27), making it easily observable from the southern hemisphere.

What is a red dwarf and why are they so numerous among nearby stars?

Red dwarfs are low-mass stars (0.08 to 0.6 solar masses) and low temperature (2,000 to 4,000 K), of spectral type K or M. They are the most abundant stars in the Milky Way, representing about 70% of all stars. Their low luminosity makes them difficult to observe at great distances, but they dominate the population of stars close to the Sun: in the list of the 50 closest stars, over 80% are red dwarfs. They have a long lifespan (several tens of billions of years) and can host exoplanets in the habitable zone (like Proxima Centauri b), but their intense flare activity can threaten the atmospheres of these planets.

What is the Hill sphere and why is it important for nearby stars?

The Hill sphere is the region around a celestial body where its gravitational attraction dominates over that of other bodies (such as a neighboring star or the galaxy). For the Solar System, its radius is about 1.96 light-years; for Alpha Centauri, it is 2.28 light-years. Since the distance between the two systems is 4.37 light-years, their Hill spheres do not overlap, but they are relatively close. This means that celestial objects (like brown dwarfs or rogue exoplanets) could be located in the boundary zone, without being captured by either system. This concept is crucial for understanding gravitational interactions and possible material exchanges between nearby stellar systems.

How are the distances to nearby stars measured with precision?

The distances to nearby stars (less than a few hundred light-years) are measured using parallax: the apparent angular displacement of the star against the background sky as the Earth moves around the Sun. The Hipparcos catalog (ESA) provided parallax measurements for over 100,000 stars with an accuracy of about a millisecond of arc. The Gaia mission, Hipparcos' successor, has improved this precision by a factor of 100, allowing the measurement of distances for over a billion stars with unprecedented accuracy. For the closest stars, like Alpha Centauri, the parallax is relatively large (about 0.75 arcseconds), allowing the distance to be determined with an uncertainty of less than 1%. The formula relating parallax p (in arcseconds) to distance d (in parsecs) is: d = 1/p.