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View from this system

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The sky from Alpha Centauri AB would appear much as it does from the Earth, except that Centaurus would be missing its brightest star. The Sun would appear as a yellow star of apparent magnitude +0.47, roughly the same as the average brightness of Betelgeuse from Earth. It would be at the antipodal point of Alpha Centauri AB's current right ascension and declination, at 02h 39m 35s +60° 50′ (2000), in eastern Cassiopeia, easily outshining all the rest of the stars in the constellation. With the placement of the Sun east of the magnitude 3.4 star Epsilon Cassiopeiae, nearly in front of the Heart Nebula, the "W" line of stars of Cassiopeia would have a "/W" shape.note
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Planetary system

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Confirmed planets edit Proxima Centauri b edit Proxima Centauri b is a terrestrial planet discovered in 2016 by astronomers at the European Southern Observatory. It has a minimum mass of 1.17 M ⊕ (Earth masses) and orbits approximately 0.049 AU from Proxima Centauri, placing it in the star's habitable zone. Proxima Centauri c edit Proxima Centauri c was formally discovered and confirmed in 2020 and is a likely super-Earth or mini-Neptune. It has a mass of roughly 7 M ⊕ and orbits about 1.49 AU from Proxima Centauri with a period of 1,928 days (5.28 yr). In June 2020, a large ring system encircling the planet was possibly detected. Controversial and hypothetical planets edit Alpha Centauri Bb edit In 2012, a planet around Alpha Centauri B was announced, Alpha Centauri Bb, but in 2015 a new analysis concluded that it almost certainly does not exist and was just a spurious artefact of the data analysis. Unconfirmed discovery edit Whilst ruling out the existence of Alpha Centauri Bb,...
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Observation

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To the naked eye, Alpha Centauri AB appears to be a single star, the brightest in the southern constellation of Centaurus. Their apparent angular separation varies over about 80 years between 2 and 22 arcsec (the naked eye has a resolution of 60 arcsec), but through much of the orbit, both are easily resolved in binoculars or small telescopes. At −0.27 apparent magnitude (combined for A and B magnitudes), Alpha Centauri is fainter only than Sirius and Canopus. It is the outer star of The Pointers or The Southern Pointers , so called because the line through Beta Centauri (Hadar/Agena), some 4.5° west, points to the constellation Crux—the Southern Cross. The Pointers easily distinguish the true Southern Cross from the fainter asterism known as the False Cross. South of about 29° S latitude, Alpha Centauri is circumpolar and never sets below the horizon.note North of about 29° N latitude, Alpha Centauri never rises. Alpha Centauri lies close to the southern horizon when viewed from the...
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