Editing Alpha Centauri (section)

== View from this system ==
{{more citations needed|section|date=March 2023}}
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[[File:Sky-from-alpha-centauri.jpg|thumb|upright=1.2|Looking towards the sky around [[Orion (constellation)|Orion]] from Alpha Centauri with [[Sirius]] near [[Betelgeuse]], [[Procyon]] in [[Gemini (constellation)|Gemini]], and the Sun in [[Cassiopeia (constellation)|Cassiopeia]] generated by [[Celestia]] |alt=Simulated night-sky image centred on Orion labelled with constellation names in red and star names in yellow, including Sirius very close to Betelgeuse and the Sun near Cassiopeia.]]
[[File:Sun from Alpha Centauri.png|thumb|upright=1.2|Simulated night-sky image with a "W" of stars from [[Cassiopeia (constellation)|Cassiopeia]] connected by lines, and the Sun, labeled "Sol", as it would appear to the left of the "W"]]

The sky from {{nobr|α Centauri AB}} would appear much as it does from the Earth, except that [[Centaurus]]'s brightest star, being {{nobr|α Centauri AB}} itself, would be absent from the constellation. The Sun would appear as a white star of [[apparent magnitude]] +0.5,<ref>{{cite magazine |first = Bob |last = King |date=2022-02-02 |title=See the Sun from other stars |department = Explore the Night Sky |magazine=Sky & Telescope |url=https://skyandtelescope.org/astronomy-blogs/explore-night-bob-king/see-the-sun-from-other-stars/ |access-date=2023-02-22}}</ref> roughly the same as the average brightness of [[Betelgeuse]] from Earth. It would be at the [[antipodal point]] of {{nobr|α Centauri AB's}} current [[right ascension]] and [[declination]], at {{RA|02|39|36}} {{DEC|+60|50|02.308}} (2000), in eastern [[Cassiopeia (constellation)|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.<ref>{{cite web |last=Gilster |first=Paul |title=Alpha Centauri and the new astronomy |website=Centauri Dreams |date=2012-10-16 |url=https://www.centauri-dreams.org/2012/10/16/alpha-centauri-and-the-new-astronomy/ |access-date=2023-02-22}}</ref>

Other nearby stars' placements may be affected somewhat drastically. [[Sirius]], at 9.2 light years away from the system, would still be the brightest star in the night sky, with a magnitude of -1.2, but would be located in [[Orion (constellation)|Orion]] less than a degree away from Betelgeuse. [[Procyon]], which would also be at a slightly further distance than from the Sun, would move to outshine [[Pollux (star)|Pollux]] in the middle of [[Gemini (constellation)|Gemini]].

A planet around either {{nobr|α Centauri A}} or B would see the other star as a very bright secondary. For example, an Earth-like planet at {{nobr|1.25 AU }} from {{nobr|α Cen A}} (with a revolution period of 1.34&nbsp;years) would get Sun-like illumination from its primary, and {{nobr|α Cen B}} would appear 5.7–8.6&nbsp;magnitudes dimmer (−21.0 to −18.2), 190–2,700&nbsp;times dimmer than {{nobr|α Cen A}} but still 150–2,100&nbsp;times brighter than the full Moon. Conversely, an Earth-like planet at {{nobr|0.71 AU }} from {{nobr|α Cen B}} (with a revolution period of 0.63&nbsp;years) would get nearly Sun-like illumination from its primary, and {{nobr|α Cen A}} would appear 4.6–7.3&nbsp;magnitudes dimmer (−22.1 to −19.4), 70 to 840&nbsp;times dimmer than {{nobr|α Cen B}} but still 470–5,700&nbsp;times brighter than the full Moon.

Proxima Centauri would appear dim as one of many stars, being magnitude 4.5 at its current distance, and magnitude 2.6 at periastron.<ref>{{cite web |title=The view from Alpha Centauri |date=2020-08-28 |department = Alien Skies |website = Drew Ex Machina |url=https://www.drewexmachina.com/2020/08/28/alien-skies-the-view-from-alpha-centauri/ |access-date=2023-02-22}}</ref>