Mystery re star?????

[kjfenby]

Can anyone tell me the name of a small vivid ruby red star (not visible to the unaided eye) that is located somewhere in the vicinity of Menkent (in Centaurus) / Hydra. I came across this star one evening whilst viewing the night sky in July, but am not exactly certain of its location. The star was one of the most spectacular sights I have seen for a while but can find no reference to it in any of my sky charts.

[Mick (Michael)]

Maybe you can find what you are looking for here http://www.iceinspace.com.au/forum/s...ad.php?t=39221

[Kevnool (Kev)]

Are you sure your not trying to find the carbon star ESB365 in Crux right next to Mimosa or Beta Crux.

Thats the only one i know in the region off the top off the head.
Cheers Kev.

[kustard (Simon)]

That's the one I was thinking it could be Kev, can't think of any other.

[kjfenby]

Thank you very much indeed for the link. I found that someone had posted a spreadsheet containing a list of carbon stars. I will troll through these as the star I saw is most likely one of those on that list.

Thanks again

[kjfenby]

Thank you for the response, but I don't believe it was ESB365 as I was not looking at the Crux.

[GeoffW1 (Geoff)]

Hi,

There are, close to Menkent

2 Cent, HR 5192 (SAO 204875), 13h 50m 07s, -34 30' 28", a type M star mag 4.2

HD 123110 (SAO 205184), 14h 07m 11s, -34° 57' 11.6", a type M star mag 6.9

HD125343 (SAO205436), RA: 14h 20m 26.35s, DE:-36° 54' 38.4", a type M star mag 7.0, with a companion at sep 4 sec, mag 11.5

Cheers

[Robh (Rob)]

Your description of it as a "vivid ruby red star" might indicate it to be a carbon star. However, how red a star appears depends on many factors:
where it might be in its cycle (carbon stars are generally variable stars), how low it is in the sky, the transparency of the atmosphere and the actual optics of your telescope+eyepiece.

Carbon stars generally have a B-V colour index greater than 2. For example V Hydrae has a colour index of 4.5, Hind's Crimson Star (R Leporis) has a colour index of 3.5. DY Crucis (Ruby Crucis) next to Mimosa has a colour index of 5.8.

There don't seem to be any "bright" carbon stars within cooee of theta Centauri.
I can only find a few possible candidates and they are all around 11th magnitude.
TYC 7288-1528-1 (14 03 37.36, -34 59 37.8) has magnitude 10.78 and colour index 2.49. It is about 1.6 degrees from Menkent.
TYC 7288-1181-1 (14 06 16.56, -34 50 09.5) has magnitude 10.92 and colour index 2.14. It is also about 1.6 degrees from Menkent and about half a degree from the previous star.
A redder star is TYC 7803-0011-1 (14 04 37.71, -37 35 18.1), magnitude 11.12. It has a colour index of 3.41 but unfortunately is 1.3 degrees from Menkent in the opposite direction to Hydra.

Regards, Rob