This is a Type IIb/III[8] planetary nebula with a low expansion velocity of 15 km/s.[9] The chemical abundances in the shell indicate that the progenitor had only undergone partial conversion of carbon into nitrogen when its life span came to an end.[9] The morphology shows point symmetry around the center. Overall it is rectangular in shape, and has two pairs of higher density knots that are symmetric around the middle, aligned along position angles of approximately 30° and 163°. These display a slightly enhanced abundance of nitrogen compared to the rest of the nebula and are photoionized on the side facing the central star.[8] The symmetrical shape of the nebula may have arisen from jets emerging from both sides of a disk about the central star.[10]
Gallery
NGC 5307 can be seen primarily in the southern hemisphere.[11]
^Streicher, Magda (June 2008). "Centaurus, a constellation like no other". Monthly Notes of the Astronomical Society of South Africa. 67 (5 and 6): 95–99. Bibcode:2008MNSSA..67...95S.
^Bond, Howard E. (2000). "Binarity of Central Stars of Planetary Nebulae". In Kastner, J. H.; Soker, N.; Rappaport, S. (eds.). Asymmetrical Planetary Nebulae II: From Origins to Microstructures. Asymmetrical Planetary Nebulae II: From Origins to Microstructures. ASP Conference Series. Vol. 199. p. 115. arXiv:astro-ph/9909516. Bibcode:2000ASPC..199..115B. ISBN1-58381-026-9.