by Ron Bhanukitsiri
I've always been envious of southern observers. Objects so beautiful and yet so down under beyond our reaches. So tonight under an unsteady sky, gust of winds on occasion, much light pollution from the western and southern sky, and LM=4.9, the TV-102 Light Cup bursted open the Eight-Burst Planetary Nebula!
But first, there were some loose ends to be tied. Someone suggested NGC 1788 on Astromart. The TV-102 located this mag 9 (est.) reflection nebula in Orion. At 22x (Pentax 40mm XL), I saw very faint nebulosity with a star seen inside it. Nebulosity very dim at 44x (20mm TV Plossl and 73x (12mm Radian); there is a 10th magnitude star GSC 4754:1474 embedded inside the nebula. The nebula is enclosed by four squarish stars: SAO 131770, GSC 4754:1473, SAO 131783 and SAO 131789. Impressively, a 2nd knot popped into view at 110x (8mm Radian - the Planetary Plucker) and lies in the direction of SAO 131783. This 2nd knot is seen clearer at 146x (6mm Radian). It appears that there is another star embedded in the center of this 2nd knot as well, but it blinked in and out. Even better at 176x (5mm Radian), both nebulosity now seem to merge. All four stars still fit entirely into the FOV! Here's a very nice picture I found on the web. http://www.noao.edu/outreach/aop/observers/n1788.html
A few weeks ago, there was a seemily hurricane force wind. I opened the back door and stucked the Light Cup's eye out of the door and panned around with the 40mm Pentax XL and ran across a very bright nebula and took note of it. Tonight, I revisited NGC 2467 for a real look. This one is a biggie at 16' across and a bright mag 9.0. Normally, the Light Cup hasn't done well with NGC diffused nebula, but this one is a real gem. Easily found at 22x by star hopping from a pretty orange star, Xi Puppis. Nebulosity is seen at this low magnification, large and noticably brighter than NGC 1788. The view improved considerably at 44x and appeared roundish with an orange star in the center. At 73x, it is a real beauty, flanked by 3 stars at one end. Fairly, bright nebulosity with lots of tiny little stars scattered throughout the FOV. Best view at 146x and higher brightness on one end. Defintely, a very nice diffused nebula without a need for any filter in a 4" refractor.
Before I attempted NGC 3132, the Eight-Burst Planetary, I tried the Carina Galaxy. No luck, the whole FOV was bright gray and it was way too low! Took a while for the Light Cup to locate NGC 3132 (Eight-Burst Planetary) with surface brightness of mag 9.4 because I was totally unfamiliar with constellation so low in the sky. In fact, it was only 15 degree high in the sky! At 22x, I wasn't sure where it was and 44x with only 50 degree AFOV wasn't much help. So I reverted to the 30mm Ultima (30x) and the PN was *bursted* by the TV-102 Light Cup as non-stellar and now 44x showed it clearly non-stellar. 73x showed nebulosity clearly; its mag 10.1 central star could be easily seen. At 110x, it looks about the size of Jupiter at at 73x, very bright despite it being very low in the sky. Stunningly, at this magnification, it looks like a jade ball (since its color is green) trapped inside a crystal (American) football (or a rugby) formed by the following stars ranging from mag 9.5 to mag 11: GSC 7711:1393, GSC 7711:1489, GSC 7711:1075, GSC 7711:1721, GSC 7711:496, GSC 7711:2523, GSC 7711:1211, GSC 7711:1719. All stars just fit into the FOV of the 8mm Radian. At 146x, the PN has a similar surface brightness as the mag 8.5 star SAO 221781. Greenish and bright with the central star still clear seen. Using my "jack-ass" technique (i.e. jacket covering the head ;-), grainy texture could now be detected at 176x while retaining its green color and is still bright! This PN definitely goes into the Light Cup favorite bucket.
Although my research have shown that NGC 3132 got the name Eight-Burst from the photographs, I couldn't figure out why however. Then, the Light Cup and the 8mm TV Radian bang my head as I was grabbing another EP from the case:
8 surrounding stars that looked like a football = Eight Burst! Got it ;-)?
So lookout you southerners, the TV-102 Light Cup is coming to stake claim on your many lovely DSO ;-).