Title: Alpha Centauri
Content:  an orbital period of 79.91 years. Their elliptical orbit is eccentric, so that the distance between A and B varies from 35.6 AU (astronomical units), or about the distance between Pluto and the Sun, to 11.2 AU, or about the distance between Saturn and the Sun. Alpha Centauri C, or Proxima Centauri, is a small and faint red dwarf (Class M). Though not visible to the naked eye, Proxima Centauri is the closest star to the Sun at a distance of 1.30 pc, slightly closer than Alpha Centauri AB. Currently, the distance between Proxima Centauri and Alpha Centauri AB is about 13000 AU, equivalent 
Title: Alpha Centauri
Content:   The A and B components of Alpha Centauri have an orbital period of 79.91 years. Their orbit is moderately eccentric, e=0.5179; their closest approach or periastron is 11.2 AU, or about the distance between the Sun and Saturn; and their furthest separation or apastron is 35.6 AU, about the distance between the Sun and Pluto. The most recent periastron was in August 1955 and the next will occur in May 2035; the most recent apastron was in May 1995 and will next occur in 2075. Viewed from Earth, the apparent orbit of A and B means that their separation and position angle (PA) are in continuous change throughout their projected orbit. Observed stellar positions in 2019 are separated by 4.92 arcsec through the PA of 337.1°, increasing to 5.49 arcsec through 345.3° in 2020. The closest recent approach was in February 2016, at 4.0 arcsec through the PA of 
Title: Alpha Centauri
Content:  The observed maximum separation of these stars is about 22 arcsec, while the minimum distance is 1.7 arcsec. The widest separation occurred during February 1976, and the next will be in January 2056. Alpha Centauri C is about 13000 AU from Alpha Centauri AB, equivalent to about 5% of the distance between Alpha Centauri AB and the Sun. Until 2017, measurements of its small speed and its trajectory were of too little accuracy and duration in years to determine whether it is bound to Alpha Centauri AB or unrelated. Radial velocity measurements made in 2017 were precise enough to show that Proxima Centauri and Alpha Centauri AB are gravitationally bound. The orbital period of Proxima Centauri is approximately 547,000 years, with an eccentricity of 0.50 ± 0.08, much more eccentric than Mercury's. Proxima Centauri comes within 4,300 AU of AB at periastron, and its apastron occurs at 13,000 AU.
Title: Alpha Centauri
Content:  around 22.4 km/s towards the Solar System. This gives a speed with respect to the Sun of 32.4 km/s, very close to the peak in the distribution of speeds of nearby stars. Since Alpha Centauri AB is almost exactly in the plane of the Milky Way as viewed from Earth, many stars appear behind it. In early May 2028, Alpha Centauri A will pass between the Earth and a distant red star, when there is a 45% probability that an Einstein ring will be observed. Other conjunctions will also occur in the coming decades, allowing accurate measurement of proper motions and possibly giving information on planets.
Title: Alpha Centauri
Content:  edge of Alpha Centauri B's habitable zone, which extends from 0.5 to 0.9 AU from the star. Certain special assumptions, such as considering that the Alpha Centauri pair may have initially formed with a wider separation and later moved closer to each other (as might be possible if they formed in a dense star cluster), would permit an accretion-friendly environment farther from the star. Bodies around Alpha Centauri A would be able to orbit at slightly farther distances due to its stronger gravity. In addition, the lack of any brown dwarfs or gas giants in close orbits around Alpha Centauri make the likelihood of terrestrial planets greater than otherwise. A 
Title: Proxima Centauri
Content:  Based on a parallax of 768.067 mas, published in 2020 in Gaia Data Release 3, Proxima Centauri is 4.2465 ly from the Sun. Previously published parallaxes include: 768.5 mas in 2018 by Gaia DR2, 768.13 mas, in 2014 by the Research Consortium On Nearby Stars; 772.33 mas, in the original Hipparcos Catalogue, in 1997; 771.64 mas in the Hipparcos New Reduction, in 2007; and 768.77 mas using the Hubble Space Telescope fine guidance sensors, in 1999. From Earth's vantage point, Proxima Centauri is separated from Alpha Centauri by 2.18 degrees, or four times the angular diameter of the full Moon. Proxima Centauri also has a 
Title: Proxima Centauri
Content:  approach distance of 2.90 ly in about 27,400 years, followed by a 2014 study by C. A. L. Bailer-Jones predicting a perihelion approach of 3.07 ly in roughly 26,710 years. Proxima Centauri is orbiting through the Milky Way at a distance from the Galactic Centre that varies from 8.3 to 9.5 kpc, with an orbital eccentricity of 0.07.  Ever since the discovery of Proxima Centauri, it has been suspected to be a true companion of the Alpha Centauri binary star system. Data from the Hipparcos satellite, combined with ground-based observations, were consistent with the hypothesis that the three stars are a bound system. For this 
Title: Alpha Centauri
Content:  own accurately determined parallax for 61 Cygni in 1838. For this reason, Alpha Centauri is sometimes considered as the second star to have its distance measured because Henderson's work was not fully acknowledged at first. (The distance of Alpha Centauri from the Earth is now reckoned at 4.396 ly.)  Later, John Herschel made the first micrometrical observations in 1834. Since the early 20th century, measures have been made with photographic plates. By 1926, William Stephen Finsen calculated the approximate orbit elements close to those now accepted for this system. All future positions are now sufficiently accurate for visual observers to 
Title: Alpha Centauri
Content:  For other uses, see Alpha Centauri (disambiguation). "α Centauri" redirects here. It is not to be confused with a Centauri or A Centauri. "Toliman" redirects here. For other uses, see Toliman (disambiguation). Alpha Centauri is a gravitationally bound system of the closest stars and exoplanets to our Solar System at 4.37 light-years (1.34 parsecs) from the Sun. The name is Latinized from α Centauri, and abbreviated Alpha Cen or α Cen. It is a triple star system, consisting of the three stars: α Centauri A (officially Rigil Kentaurus), α Centauri B (officially Toliman), and the closest star α Centauri C (officially Proxima Centauri). Alpha Centauri 
Title: Alpha Centauri
Content:   Based on the system's common proper motion and radial velocities, Alpha Centauri will continue to change its position in the sky significantly and will gradually brighten. For example, in about 6,200 AD, α Centauri's true motion will cause an extremely rare first-magnitude stellar conjunction with Beta Centauri, forming a brilliant optical double star in the southern sky. It will then pass just north of the Southern Cross or Crux, before moving northwest and up towards the present celestial equator and away from the galactic plane. By about 26,700 AD, in the present-day constellation of Hydra, Alpha Centauri will reach perihelion at 0.90 pc away, though later calculations suggest that this will occur in 27,000 AD. At nearest approach, Alpha Centauri will attain a maximum apparent magnitude of −0.86, comparable to present-day magnitude of Canopus, but it will still not surpass that of Sirius, which will brighten incrementally over the next 60,000 years, and will continue to be the brightest star as seen from Earth (other than the Sun) for the next 210,000 years.

Question: what is alpha centauri's approximate distance from earth?
Answer: 4.37 light-years.