The sky around vdB 125 at true scale, north up and east left, with stars to magnitude 8. The circles show the field of a low-power eyepiece and of 10×50 binoculars.
vdB 125 is a reflection nebula in Aquila, 1,270 light-years away
vdB 125 is a reflection nebula in the constellation Aquila, 1,270 light-years away. spans 2.4′ of sky, about 0.9 light-years across. It is a telescope object, 6 inches or larger, and it is highest in the evening sky in August.
Nebula: a cloud of gas and dust. Emission nebulae glow on their own, lit by ultraviolet light from hot young stars; reflection nebulae shine by starlight scattered from dust; dark nebulae block the light behind them.
vdB 125 is vdB 125 in the Van den Bergh catalog of reflection nebulae
Sidney van den Bergh listed it in his catalog of reflection nebulae (1966), drawn from the Palomar Sky Survey. He chose nebulae lit by a star bright enough to appear in the Bonner and Cordoba star catalogs. The star that lights it is HD 182830, F0, magnitude 8.1. He rated it very faint in brightness and blue in color.
Finding vdB 125 from Altair
vdB 125 lies 9.0° northwest of Altair, the magnitude 0.8 star. A fist held at arm's length covers about 10°.
vdB 125 is highest in the evening in August
The chart gives its height above the horizon at 9 pm through the year, from 60°N to 40°S. It can be seen from the whole northern hemisphere and south to about 74°S, and never sets north of 74°N.
vdB 125 is 1,270 light-years away
The light seen from vdB 125 tonight left it about 1,270 years ago, around 756 AD. It ranks 58 of 158 by distance among the Van den Bergh nebulae. Distance source: Gaia DR3 parallax of the illuminating star via AT-HYG v3.2 (388 pc).
