VBRC-2 Planetary Nebula
“The Atomic Crystal Ball”
Wonderful Description by Sakib Rasool
Floating in the cosmos like a mystical crystal ball, VBRC 2 is a beautiful hidden gem of a planetary nebula that deserves to be more well known. One of 7 planetary nebulae catalogued by astronomers Sidney van den Bergh and Rene Racine in 1973, it has a multitude of catalogue designations. More commonly referred to as Wray 17-31, it is also known as PN G277.7-03.5 and RCW 44. It was discovered by the astronomer James Wray in 1966 and has an estimated distance of 4500 light years.
The main central shell measures 2.5 arcminutes and consists of both Ha and OIII emission with a blue ionizing central star located at its centre. The central star is hydrogen rich with traces of helium. However, this deep telescopic image reveals something not commonly seen, an outer halo with a size of 3.5x3 arcminutes. This was first discovered by the Galactic Planetary Nebula Halo Survey (GPNHS) team in August 2014 whilst analysing an image taken by GPNHS member Michael Sidonio: https://pbase.com/strongmanmike2002/wray_1731_in_vela
After applying contrast enhancement to Michael's image, faint hints of a small loop type structure were apparent. To corroborate the veracity of this structure, images of VBRC 2 from the SuperCOSMOS Ha Survey were consulted, which showed it to be the brightest part of a much larger and low surface brightness structure. This was then verified in an image commissioned by Don Goldman in March 2016 with his website now defunct. Due to its proximity to the more well known NGC 2899, a widefield image was commissioned by Marco Lorenzi in May 2022: https://app.astrobin.com/i/cw86y1
This new image is currently the clearest and deepest view of this outer halo, which just like the central shell is comprised of both Ha and OIII emission. This is likely to be material ejected during the asymptotic giant branch (AGB) phase of the previous evolution of the central white dwarf star. AGB haloes have been identified in a large number of planetary nebulae with a systematic photographic search conducted by professional astronomers for nearly half a century. Some well known examples include M57 and M97 to name a few.
Imaged in RGBHa on a Planewave CDK 24 at Observatorio El Sauce, Chile. Taken Moravian C5. 24 x 300sec for each R-G-B, 36 x 600 for each Ha-OIII and 30x600 for SII
SWOS Group, Mazlin, Forman, Magill, Hawn, Stafforini, Hanson
Description from Sakib Rasool
Enjoy, Sakib, Mark and SWOS group.