NGC 2261 – Hubble’s Variable Nebula in Monoceros

Telescope: Astro-Tech 8” f/8 Ritchey-Chretien, Orion Atlas EQ-G

Camera: QHY 367c Pro, -20C, Baader Mk III MPCC, GSO IR Blocking Filter

Guide scope: Astro-Tech 60mm, ZWO ASI120MM mini, PHD2

Exposure: 6x300sec, gain 2800, offset 50, saved as FITS, dithered every 2 images

Darks: 32, -20C, gain 2800, offset 50, saved as FITS

Flats: 64×0.3sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency

Lensed Sky Quality Meter: 18.3

Stacking: Average, 1 sigma clip

White Balance: Nebulosity Automatic

Software: SharpCap Pro, Deep Sky Stacker, Nebulosity, Photoshop

Hubble’s Variable nebula is a small, bright, fan-shaped reflection nebula in Monoceros (the Unicorn). The bright tip of the nebula is not just a star, but a dense nebula hiding a binary star system at its core (R Mon). Clouds of dust are believed to orbit this system, casting shadows up onto the veil causing the overall brightness of the nebula to vary. Time lapse sequences spanning weeks of time show the shadows sweeping across the veil.

This was an interesting image set taken on the evening of February 26^th. It was a partly cloudy evening with a lot of haze. I let y camera run until the nebula reached the meridian and sorted through them to find the usable subs. The results is pretty good for only 6 subs! Visually, NGC 2261 appears very much like a beautiful fan-shaped comet. In fact, it appears more like a comet than most faint comets! NGC 2261 is presently high in the east as the sky darkens.