Object name: V-AQL

Designation(s): V-AQL,

V Aquila is a rather famous carbon star. I\'ve often seen it visually as redder than more famous carbon stars. Though these stars are variable and their color changes through the cycle. It is a double star with a separation of 0.2\" so don\'t expect to see it visually. Since the red color is so strong I assume the companion is much fainter than the carbon star. I can\'t find an estimate of the companion\'s brightness. Much about the star seems to vary with the source. I find even the same source saying its distance is ~400 parsecs and that its distance is ~1200 light-years when 400 parsecs would be about 1300 light-years. I don\'t trust either. Its B-V value varies as well but that may be due to where in the cycle it is measured. I\'ve seen it red as a stop light and more orange than red. I have no idea where in the cycle it was when I caught it on September 12, 2010, UT.

Trying to capture its color as seen visually is difficult. Monitors are so limited that if it is red enough at the core it is way too dim compared to the background stars. If you brighten it red is already saturated so all that does is bring up green and blue turning it orange then yellow. I compromised leaving it dimmer compared to background stars than it really is. The color ratios are close to the RGB ratios.

The image is rather a composite. Background stars were 5 one minute images while RGB data was 9 one minute images. Even then the L went fainter with less noise than the color data. So I processed it as LRGB rather than RGB as I planned. V Aquila however saturated in red light so fast I was limited to 5 second exposures for it. I used 24 5 second exposures in each color to make an RGB image of the star which was then matted in over the LRGB version which was so saturated it was bright yellow-white.

14\" LX200R @ f/10, see text for exposure, STL-11000XM, Paramount ME