The sky around vdB 148 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 148 is a reflection nebula in Cepheus, 4,750 light-years away
vdB 148 is a reflection nebula in the constellation Cepheus, 4,750 light-years away. spans 3.4′ of sky, about 4.7 light-years across. It is a telescope object, 6 inches or larger, and it is highest in the evening sky in October.
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 148 is vdB 148 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 239856, F2Iab, magnitude 8.5. He rated it faint in brightness and blue in color.
Finding vdB 148 from ζ Cep
vdB 148 lies 2.0° south of ζ Cep, the magnitude 3.4 star. That is within one binocular field.
vdB 148 is highest in the evening in October
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 34°S, and never sets north of 34°N.
vdB 148 is 4,750 light-years away
The light seen from vdB 148 tonight left it about 4,750 years ago. It ranks 146 of 158 by distance among the Van den Bergh nebulae. Distance source: Gaia DR3 parallax of the illuminating star via AT-HYG v3.2 (1456 pc).
