Rho Ophiuchi is a triple star system (on the left side of the picture) in constellation Ophiuchus. The light from the stars is partially absorbed by the gas, which makes the blue reflection nebula visible. Smaller reflection nebula called IC 4603 is located on the right. The picture shows just small frame of significantly bigger nebula, called Rho Ophiuchi complex, which combines star Antares, globular cluster M4 and many more reflection, emission and dark nebulae. In order to capture the whole complex, one has to use significantly shorter focal length, like 130 – 200 mm.

The picture was taken under dark skies of Fuerteventura and it’s a stack of 73 pictures, 3 minutes each, which makes total integration time 219 minutes.

Technical details:

TelescopeNewton 150/600 mm
Aperture150 mm
Focal length570 mm
MountRainbow Astro RST 135
AutoguidingZWO 174MM, Guidescope 30 mm
CameraZWO 071 Pro @-0°C
CorrectorTS MaxField
FiltersNo
Exposure73x180s, Gain 94, bin 1x1,
Date2020-07-21