This is a roughly symmetrical, bipolar nebula with an expansion velocity of12.7 to 17.3 km/s.[7] It includes some knots, filaments, and probably a double-shell structure.[8] NGC 6153 has a Peimbert type of I, indicating it is helium and nitrogen rich and the progenitor was athin disk star.[9] A 1986 analysis ofspectra showed this to be an unusual nebula. Nearly all elements in the nebula are overabundant, particularly for nitrogen, neon, sulfur, and argon. In some cases being higher in abundance compared to any other nebula.[7] It was proposed that this discrepancy occurs due to cold, metal-rich, hydrogen deficient knots that have been included in the nebula.[10]
An analysis ofGaia data suggests that the central star may be abinary system.[11] A binary system could explain the abundance discrepancy.[12] While on the cooling track, a white dwarf can undergo a finalthermal pulse, causing the star to swell into a helium burning giant that follows nearly the same evolutionary track as the earlier star.[13]
^abPottasch, S. R.; et al. (February 1986). "Abundances in the planetary nebula NGC 6153".Astronomy and Astrophysics.155:397–401.Bibcode:1986A&A...155..397P.
^Anandarao, B. G.; Banerjee, D. P. K. (August 1988). "High resolution observations of the planetary nebulae NGC 6153 and IC 4593".Astronomy and Astrophysics.202:215–218.Bibcode:1988A&A...202..215A.
^Iben, I., Jr.; et al. (January 1983). "On the evolution of those nuclei of planetary nebulae that experience a final helium shell flash".Astrophysical Journal.264:605–612.Bibcode:1983ApJ...264..605I.doi:10.1086/160631.{{cite journal}}: CS1 maint: multiple names: authors list (link)
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