Howell-Crisp 1 (HoCr 1)
RA: 06 21 41.0
Dec: +23 35 13
Type: PN candidate (likely)
Size: 50"
Mag: ~15V
Michael Howell "discovered" HoCr 1 in early 2006 as a possible planetary nebula on an image he made of the region surrounding IC 443 and IC 444. Howell's web page has a number of images of this object. At the same time Richard Crisp, a California amateur, also provided an image. This object is clearly visible on the DSS, though it had not been analyzed, except for an earlier IRAS detection (IRAS 06185+2336). You'll find it 11' SSW of 7.4-magnitude HD 44251 and 37' ENE of the reflection nebula IC 444.
HoCr 1_wikisky.jpg
Dr. George Jacoby, Director of the WIYN Observatory 3.5 meter Telescope at Kitt Peak, Tucson, AZ provided a high-resolution image and it was announced as a possible planetary nebula.
HoCr 1.jpg
Finally, it was included in the 2010 paper "Searching for Faint Planetary Nebulae Using the Digital Sky Survey" in Publications of the Astronomical Society of Australia as a probable or confirmed planetary.
I first viewed this object back in November 2006, along with Mark Wagner and Ray Cash. I'm sure this was among the very first visual sightings. Ray first took a stab at it with his 13-inch using a UHC filter and it was marginal in partially cloudy conditions. I later took a look in my 18" Starmaster when the sky was clear and it was definitely visible, though only seen part of the time at 115x using a DGM Optics NPB filter. It appeared as an extremely low surface brightness hazy spot, perhaps 30" in diameter. A trio of faint stars 1' west pinpointed the location. Mark felt the object had an irregularly round shape with an occasional sharp edge on its SW perimeter.
A couple of weeks ago, I picked up HoCr 1 unfiltered as 200x in my 24-inch f/3.7 Starstructure, though it required knowing the exact location. Adding a NPB filter, it was visible continuously, though very faint, roundish, 30" diameter, low surface brightness. A mag 15 star is at the NE edge.
HoCr 1_widefield.jpg
I'm guessing a 10" to 12" is the minimum aperture to pick up this new planetary, but who knows unless you take a look.
"GIVE IT A GO AND LET US KNOW"
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