The sky around vdB 104 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 104 is a reflection and emission nebula in Scorpius, 697 light-years away
vdB 104 (LBN 1104, Ced 130) is a reflection and emission nebula in the constellation Scorpius, 697 light-years away. spans 1° of sky, about 12 light-years across. It is a telescope object, 6 inches or larger, and it is highest in the evening sky in July.
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 104 is vdB 104 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 Alniyat (Sigma Sco), HD 147165, B1III, magnitude 2.9. He rated it moderate in brightness and intermediate in color.
Finding vdB 104 from Antares
vdB 104 lies 2.0° northwest of Antares, the magnitude 1.1 star. That is within one binocular field.
vdB 104 is highest in the evening in July
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 southern hemisphere and north to about 64°N, and never sets south of 64°S.
vdB 104 is 697 light-years away
The light seen from vdB 104 tonight left it about 697 years ago, around 1329 AD. It ranks 29 of 158 by distance among the Van den Bergh nebulae. Distance source: Hipparcos 2007 parallax via HYG v4.1 (HR 6084, illuminating star).
