NGC 6302 (The Butterfly Nebula) is an extremely energetic and rapidly expanding bipolar planetary nebula (PN). If the central source is a single star, then its apparent location in an H-R diagram places it among the most massive, hottest, and presumably rapidly evolving of all central stars of PNe. Our proper motion study of NGC 6302, based on Hubble Space Telescope WFC3 images spanning 11 yr, has uncovered at least four different pairs of uniformly expanding internal lobes ejected at various times and orientations over the past two millennia at speeds ranging from 10–600 km s−1. In addition, we find a pair of collimated off-axis flows in constant motion at ∼770 ± 100 km s−1within which bright [Fe
- Award ID(s):
- 1813298
- PAR ID:
- 10356033
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 927
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 100
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract ii ]feathers are conspicuous. Combining our results with those previously published, we find that the ensemble of flows has an ionized mass >0.1M ⊙and its kinetic energy, between 1046and 1048erg, lies at the upper end of gravity-powered PNe ejection processes such as stellar mergers or mass accretion. We assemble our results into a plausible historical timeline of ejections from the nucleus and suggest that the ejections are powered by gravitational infall. -
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3847/1538-4357/ac51cd
