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Tom Mazanec
2008-Mar-30, 03:06 PM
What would Proxima Centauri look like from Alpha Centauri? How bright would it be and how bright would its flares be? What constellation would it be located in?

GOURDHEAD
2008-Mar-30, 05:30 PM
A or B?

01101001
2008-Mar-30, 06:02 PM
Don't know if it will help: Extrasolar Visions has some star maps from Proxima Centauri B at Extrasolar Visions :: Proxima Centauri b (http://www.extrasolar.net/planettour.asp?PlanetID=67) (and maybe from other nearby bodies at the site).

I'm not even sure I spot Alpha Centauri (or Rigil Kent) from there -- must only be about 10000 AU distant. Maybe the name collided with another, though. Still, nothing stands out as a bright nearby neighbor though -- nothing like bright Sirius or Canopus.

In the reverse view, were it to be available there (I didn't look), from Alpha Centauri it might be really hard to spot the dimmer Proxima.

But, the generated star maps could be junk. I don't know how reliable they are.

Edit: I took another look at the maps and noticed the title/description: "centering on Rigil Kentaurus system". Perhaps that is why I'm not seeing members of the Alpha Centauri system: they are all sort of under my feet.

Eckelston
2008-Mar-30, 06:18 PM
Proxima is 0.21 ly away from the A and B which is about 1/20 its distance to the Sun. So it is 400 times or about 6.5 magnitudes brighter. Proxima being a 11th magnitude star that gives 4.5, not a very unusual sight for the casual observer.

RalofTyr
2008-Mar-30, 07:06 PM
From AC2, Proxima would be the third brightest star in the sky. It would be brighter than any star in our system. From Proxima, the Alpha Centauri, A and B, would appear as one star, geting brighter and dimmer as they orbit eachother.

This, I got from Celestia. And Sirius is in the Orion constellation.

Check out Extra Solar Skies

Eckelston
2008-Mar-30, 07:35 PM
From AC2, Proxima would be the third brightest star in the sky. [...]
This, I got from Celestia. And Sirius is in the Orion constellation.

Check out Extra Solar Skies

Are you sure you're not looking at the nearest stars list? I tried the same and it said Proxima's apparent magnitude is 4.63, not among the 500 brightest stars visible from Alpha Centauri B.

grant hutchison
2008-Mar-30, 08:17 PM
Yes, at mag 4.63, Proxima is fairly dim in the skies of the Alpha Cen pair, though it would be naked-eye visible. SolStation (http://www.solstation.com/stars/alp-cent3.htm) says that flares "roughly double" its brightness, which would take it into the third magnitude (assuming that "brightness" refers to visual luminosity).
It appears in the constellation of Taurus, a little to the southwest of Aldebaran and the Hyades.

Grant Hutchison

KaiYeves
2008-Mar-30, 08:41 PM
And the sun would appear as a bright star in Cassiopeia.

novaderrik
2008-Mar-30, 10:39 PM
hey, Kai, aren't you on assignment from Alpha Centauri?
what do things look like from there?

KaiYeves
2008-Apr-01, 12:53 AM
hey, Kai, aren't you on assignment from Alpha Centauri?
what do things look like from there?
No, Vega, sorry. And my path didn't take me past it, either, but I've heard it's a nice place.

tony873004
2008-Apr-01, 05:47 PM
Here's a visual magnitude javascript calculator I made:
http://orbitsimulator.com/gravity/articles/vmag9.html

Plug in 0.21 LY for d (distance) and 15.49 for M (absolute magnitude), and you'll get a visual mag of 4.53.

This is a good question, as it illustrates just how dim red dwarfs are. Even from within its own star system, it is not a standout. And although being the closest star to the Sun, it is not visible to the naked eye.

Tom Mazanec
2008-Apr-02, 06:21 PM
What about Altair? Is it in another constellation?

grant hutchison
2008-Apr-02, 06:32 PM
What about Altair? Is it in another constellation?It slides into Sagitta.

Grant Hutchison

eugenek
2008-Apr-02, 08:21 PM
The following is something I like to play around with when wondering what such-and-suck looks like from where ever.

http://www.astronexus.com/node/69

RalofTyr
2008-Apr-03, 10:38 PM
I was thinking of the 26 Draconis system, which is similar to the AC3 system.

http://www.extrasolar.net/starmaphippolar.aspx?width=500&height=500&label=1&maglimit=6&guides=1&marksol=1&hemisphere=S&originstar=HD%20160269&npra=0&npdec=90&rashift=0