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The Early Interaction of the Planetary Nebula NGC 40 with the Interstellar Medium

Jodie Martin·Kiriaki Xilouris·Noam Soker
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Abstract

We report the detection of an Halpha emission-line structure in the upstream side of the planetary nebula NGC 40, which is predicted by numerical simulations, and which is attributed to Rayleigh-Taylor instability. Such a Rayleigh-Taylor instability is expected to occur at early stages of the interaction process between the interstellar medium (ISM) and a fast moving planetary nebula, as is the case for NGC 40. We resolved the Rayleigh-Taylor instability `tongues', as well as the flatness of the nebula around the `tongues', which results from the deceleration by the ISM.

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Jodie Martin, Kiriaki Xilouris, Noam Soker. 2002-01-15. The Early Interaction of the Planetary Nebula NGC 40 with the Interstellar Medium. https://doi.org/10.1051/0004-6361%3A20020848

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