Proxima Centauri is indeed a companion to Alpha Centauri

[_Augustus_]

https://www.newscientist.com/article/2114622-proxima-centauri-really-does-orbit-its-two-bright-neighbours/

I knew it!

[wumpus]

Any relation to the fabled "Alpha Cent C" from Anthropological lore?

- The story goes there is a relatively primitive tribe with a story about multiple object connected to Alpha Cent.  There were a few things suggesting that it could have been planted by Richard Burton or just about anyone passing through with the whimsical attitude needed to botch future anthropological work.  Last time I head it mentioned, the tribe thought there were three items, and astronomers thought there were two (now three stars plus at least one planet).

- but how much closer is Proxima centauri, and how long will that stay (if it is indeed orbiting).

[kerbiloid]

Well, as Alpha Centauri is now officially Rigil Kentaurus (literally - Leg of Centaurus), and Proxima is now officially kinda the same, we now have a complete portrait of this Kentaurus,

Spoiler

 

[Nikolai]

19 hours ago, wumpus said:

but how much closer is Proxima centauri, and how long will that stay (if it is indeed orbiting).

From the article linked to in the OP: Proxima is about 0.13 light-year closer to us than A and B are, and revolves around A and B with a period of about 550,000 years.

[kerbiloid]

A dim, murrey, flashing scarlet, star is ominously glimmering in the sky of Twin Sun (aka Alpha Centauri).

It revolves around the bright, lovely double star making one turn per half-million years,
It floats through the outer rim of AlphaCen's Oort cloud, disturbs it, catches the comets and throws them towards habitable zone.

It's a Murrey Nightmare, Anger of Night, Eye of Sauron...
It has many names, and all of them are terrible.

 

For ages Alpha Centauri natives sacrifice their virgins and first-borns in hope to entreat the heartless Crimson Star.
Their planet is covered with wounds, covered with bones of beings from former epochs, mixed together.

Their legends tell us, that long time ago Pa-Sun and Ma-Sun gave birth to their first-born child. This was their only child and got used to be The One.
But ages later they decided to make one more child: the blue and green planet where the natives live.

The elder "One" became just "one" and got raged. It ran from parents into the cold and darkness of outer rim where icy rocks are mindlessly floating,
And it thirsts for revenge.

The greatest Alpha Centauri curses sound like "Let the Crimson Star _(Proxima) kiss you", "May the Murrey Eye look at you" and so on.

[Piscator]

I like this bit of mythology. However, assuming that the small, furry creatures of Alpha Centauri have a similar range of vision as humans, Proxima would likely be too unconspicous an object to attract this kind of attention. Even at the projected periastron it would only reach about second magnitude, which would be dimmer than the Sun seen from the same vantage point. (Even during flare activity, which seems to correspond to about one magnitude, as far as I can find out.)

In the infrared, it would be considerably brighter though.

[kerbiloid]

I just meant that Proxima for AlphaCen is exactly the same as hypothetical Nemezis for the Earth, according to its orbit.

[Scotius]

Well, considering that we already have found systems with increased cometary activity, but Alpha Centauri doesn't seem to be one of them, i think it isn't so bad Or maybe it actually is, but we are observing the trio during a lull in activity caused by Proxima being at the Apastron? Hmm, is 250 000 of years enough to clear a star system out of dust and debris leftover from the previous pass?

[kerbiloid]

1 hour ago, Scotius said:

but Alpha Centauri doesn't seem to be one of them

Our Oort cloud still hasn't been observed, too. It's still a mathematical generalization.

Edited December 10, 2016 by kerbiloid

[YNM]

Maybe more of a question is, actually, was it from the start ? I mean, could Proxima be a captured star or something ?

Also, I didn't know this wasn't a proven fact... I feel gullible now !