ASTRO:
     type=reflection and emission nebulae
     const=Monoceros
     mag=8.4
     dist=2400 ly
     size=15 ly
IMAGE:
     location=EB Driveway
     BrtlCls=4
     moon=18% WnCr (avg)
     exposure=CMOS OSC: 260x132s (9.6h)
EQUIPMENT:
​     optics=ES102CF APO / Stellarvue 1.0x fld-fltnr, FL=714mm, f/7.0
     camera=ZWO ASI2600MC-Pro
     filters=Optolong L-Pro LPS
     mount=Celestron AVX
     guiding=Orion 60x240mm, ZWO ASi224MC
SOFTWARE:
     acquisition=Stellarium, APT, PHD2
     processing=PixInsight (RCAstro), Photoshop, LrC

From one of the most colorful areas in the nighttime sky, this beautiful celestial still-life appears to be composed with a cosmic artist's paintbrush.  It is the open star cluster and dusty nebula NGC 2170 that shines at the upper right.   Also known as the "Angel Nebula", its cosmic clouds reflect the light of several nearby hot stars.

The Angel is joined by other bluish reflection nebulae and a compact red emission region against a large backdrop of colorful stars.  The clouds of gas, dust and hot stars are commonly found in this type of setting - a massive, star-forming molecular cloud in the constellation Monoceros.  The giant molecular cloud, Mon R2, of which the Angel is only a part, is impressively close to Earth, estimated to be appx 2,400 light-years away.  At that distance, the Angel measures about 15 light-years across.

Because it is little studied, not much is known about the Angel; but also, being a lesser-known deep sky object, not many amateur imagers know of its existence or whereabouts.  Despite its apparent anonymity, it fills the image sensors of amateurs who can find it with abundantly beautiful details.  If one looks closely, the face of the "Angel" is clearly visible.

IMAGER'S COMMENTS:This image was captured by stacking together a total of 260 subexposures captured across three (3) nights, with an average exposure time of 132s (some were shot at 120s, others at 180s) for a total integrated exposure time of 9.6h.  A Light Pollution Suppression ("LPS") filter was used in front of a One Shot Color ("OSC") camera.  The LPS filter, suppresses the wavelengths of light normally produced by man made High Pressure Sodium and Mercury Vapor streetlights.  It also provides a normal high-end roll-off that closely resembles an astronomical IRcut filter.

250220 - NGC2170 "Angel" nebula