lowpower to lookfor the magnitude 10.4 star illuminating the nebula, then you can concentrate on seeing the phantom glow with higher powers. If you live under a suburban sky, start by centering Iota Ori. Next, move 20' to the southeast, where you'll find Struve 747, a pair of 5th-magnitude stars separated by 36 '. Another 20'-hop south of Struve 747 is a magnitude 7.4 star (a). NGC 1999 lies only 15' due south of that star. Observers under dark skies can start by locating 5th-magnitude 49 Orionis, about 12 ° southwest of Iota Ori. Center that star, then move 40' to the north-northwest, to a magnitude 6 star (b). A close pair of stars (magnitudes 8 and 9) lie 15' to the southwest (c). NGC 1999 is 20' due west of that close pair. As with a small planetary nebula, once you locate the field, use averted vision and wait for a "star" to swell a full magnitude in brightness.
At23x in the 4-inch, NGC 1999 looks simply like a faint fuzzy star. Still, I was somewhat surprised at how easy it was to see. The few sources that mention NGC 1999
as a target for amateur observation mention that a 6-inch is required to see it. I believe the problem is one of proper magnification. Dwarf nebulae, especially those like NGC 1999, whichhave a relatively bright star associated with them, require substantial magnification. Fortunately, NGC 1999 is bright enough, and condensed enough, to handle high power.
Under magnifications ranging from 101 x to 303 x, NGC 1999 is a perfect example of a Class IV Herschelian object, being a star surrounded by a round milky glow, with burs, short rays, and other remarkable shapes. With time, that roundish glow becomes a broken annulus, one that appears more elliptical than round. The ellipse is tilted northwest to southeast, with the northeastern segment being the brightest part. Look for a knot in the northeastern "brow" of nebulosity due north of V380 Ori. If you use averted vision, a fine ray streaks northward from it like a comet's ion tail.
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