The sky around vdB 79 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 79 is a reflection nebula in Monoceros, 2,130 light-years away
vdB 79 is a reflection nebula in the constellation Monoceros, 2,130 light-years away. spans 5.2′ of sky, about 3.2 light-years across. It is a telescope object, 6 inches or larger, and it is highest in the evening sky in February.
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 79 is vdB 79 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 258973, A3III, magnitude 10.1. He rated it faint in brightness and moderately blue in color.
Finding vdB 79 from Alhena
vdB 79 lies 6.2° south of Alhena, the magnitude 1.9 star. Three fingers held at arm's length cover about 5°.
vdB 79 is highest in the evening in February
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 80°S, and never sets north of 80°N.
vdB 79 is 2,130 light-years away
The light seen from vdB 79 tonight left it about 2,130 years ago. It ranks 91 of 158 by distance among the Van den Bergh nebulae. Distance source: Gaia DR3 parallax of the illuminating star via AT-HYG v3.2 (652 pc).