The Eskimo or Clown Face Nebula (NGC 2392 and Caldwell 39) in Gemini is arguably the best planetary nebula within the winter sky. The Hubble House Telescope’s iconic picture from 2000 has featured closely in astronomy publications and on the Web, making the nebula some of the well-known and recognisable objects within the night time sky.
Not like lots of Hubble’s spectacular portraits although, extra humble Earth-based devices equivalent to a pair of binoculars or a small telescope can monitor it down and reveal a lot of the element that makes it such a good looking and tempting goal on lengthy winter evenings.
Easy methods to observe
Gemini lies excessive above the east-southeastern horizon by 7pm GMT. The acquainted one-two punch of its bright-star pairing of magnitude +1.6 Castor (alpha [α] Geminorum) and magnitude +1.1 Pollux (beta [β] Gem) make a very good place to begin for finding the Eskimo. Ranging from Pollux, journey south-westwards alongside the physique of dual Pollux till you land on magnitude +3.5 Wasat (delta (δ) Geminorum), then transfer south by about 1.5 levels to reach at fifth-magnitude 56 Geminorum and eventually monitor east by 1.75 levels and nudge barely north and you need to spy the nebula at RA 07h 29m 11s and Dec 20° 54’ 39”. The Eskimo culminates at about 9.30pm at a beneficial 60-degree altitude and stays on present till round 3am.
The nebula shines with an built-in magnitude of +9.2 and spans round 50 arcseconds, however its excessive floor brightness provides it an edge in the case of searching for it via 10 × 50 binoculars. A telescope within the 80mm (~three inches) class when working at moderate- to high-magnification exhibits the nebula’s internal core (~15 arcseconds throughout), which, underneath good circumstances and when near end result, can look distinctly bluish-green.
It’s fainter and mottled outer halo, or ‘Parka hood’, can begin to be distinguished via maybe a 150mm (six-inch) telescope, however you’ll want a bigger aperture or an imaging rig to deliver out some hints of these irregularities which might be so prevalent within the Hubble picture. The addition of an O-III filter will improve your viewing no matter telescope you’re utilizing.
