McNeil 1: Herbig-Haro Object (Orion) RA: 05h 46.2m / DEC: -00° 05'.8 Instrument: 10-inch Starfinder |
What happened next was the stuff of which dreams are made. Acting on Skiff's suggestion, McNeil contacted astronomer Bo Reipurth. Reipurth is an expert on Herbig-Haro objects; stellar outbursts and their associated nebulae. Within days, one of the largest telescopes in the world was being used to study McNeil's object. Images taken with the 8-meter Gemini telescope suggested that Jay McNeil had recorded a truly miraculous event: the birth of a new star. By early February, news of McNeil's Nebula was reaching the wider astronomy community via the Internet. Brian Skiff announced McNeil's Nebula to the Yahoo "Amastro" discussion list on February 9. Two days later, Chuck Detloff reported a visual observation of the object with his 24-inch Dobsonian. On February 13 in the same forum, Alan Whitman reported a successful observation with his 16-inch Dobsonian. Whitman's comment that a nearby 14.9 magnitude star was more difficult than the nebula gave me hope that McNeil-1 (McN-1) might be visible in my 10-inch The above sketch records my observation of McNeil's Nebula on the night of February 15, 2004. I made the observation from Anderson Mesa, Lowell Observatory's dark sky site about 12 miles southeast of Flagstaff, Arizona. My quest began at 7:00 pm (16 February, 02:00 UT) when I located M78 against the darkening twilight. I replaced the 8.8-mm Meade UWA eyepiece with a Meade 13.8-mm SWA paired with a TeleVue 3X Barlow. This combination produces 247X over a 15' diameter true field in my 10-inch, f/4.5 Starfinder equatorial Newtonian. I used Tom Polakis' finder chart for McNeil's Nebula to get my bearings. From M78, I moved about 10' west to 10.01 magnitude HD 290863. Then, I slewed about one eyepiece field south to look for the cometary reflection nebula Parsamyan-Petrossian 44 (PP 44). At this time, I slid one of my wife's polar fleece neck warmers over my face as a shield against stray light. Full dark adaptation would be needed for this quest. By 7:45pm, PP 44 had emerged from the darkness, visible as a fuzzy "star" with direct vision and as a slightly enlongated nebulosity with averted vision. The elongation was north and east of the brighter core over a distance of, perhaps, 15". It's the "fuzzy star" just west of center in my drawing. Two GSC stars, 4768:0175 (~12.7 magnitude) and 4768:0185 (~13.5 magnitude), were seen southeast of PP 44. These appear just inside the southern field boundary of my sketch. About 15-minutes passed before I made positive identifications of two more stars. One was GSC 4678:0681, a roughly 14.7 magnitude ember 9'.8 west of PP 44. The other was GSC 4768:0720. This ~14.9 mag. star is shown just inside the western edge of the field in my rendering. Over the course of the next 15 minutes, I occasionally detected a faint glow just inside the northern edge of the eyepiece field. This faint haze consistently appeared elongated generally north-south over an area of 60"x30". At first, this was visible just with averted vision. But by 8:30 pm, I was seeing this delicate glow with direct vision, as well. And with averted vision, a faint stellaring appeared not quite 2' to the east. The nebula, shown inside the northern limit of my sketch, was Jay McNeil's very own. The star was 14.9 magnitude GSC 4768:0171. I continued observing McNeil's Nebula for another 15-minutes until the winter chill had numbed my hands. When I finally leaned back and peered skyward, the Milky Way was visible as a broad, salty band of starlight. I swung the telescope to Saturn, which was cruising near the zenith. The seeing was quite steady at 247X and noticeably aquiver at 388X, typical of what I characterize as good-very good (7 of 10) seeing. Under similar conditions, I suspect McN-1 would be visible in a high quality 8-inch refractor. If the seeing were perfect, a 6-inch may be up to the task. Position your mouse cursor over the stars and nebulae in the above sketch for designations and magnitudes. USNO astronomer Arne Henden has determined accurate visual magnitudes for two stars: GSC 4768:0706 and GSC 4768:0171. Their Vmags are listed as unambiguous. Visual magnitude estimates for the other stars were made by averaging their R and B mag photometry, where available, or by citing the GSC photometry. In either case, magnitude estimates should only be considered as rough approximations. |
Instrument: 18-inch Obsession |
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