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Imaging and Spectroscopy of the Planetary Nebula NGC 6778

Vicente Maestro·Martin A. Guerrero·Luis F. Miranda
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Abstract

We present narrow-band images and long-slit echelle spectra of the planetary nebula (PN) NGC 6778. The data show this PN as bipolar, with a very prominent low-excitation equatorial toroid, high-excitation lobes and two pairs of collimated outflows. Morphologically, the pairs of outflows are different from each other; one is linear and oriented along the bipolar axis, the other presents an S-shape with changing orientations. Besides the different morphology, both pairs of collimated outflows present radial velocities increasing with distance from the central star and share a common origin in bright knots at the tips of the shell.

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Vicente Maestro, Martin A. Guerrero, Luis F. Miranda. 2003-10-14. Imaging and Spectroscopy of the Planetary Nebula NGC 6778. https://arxiv.org/abs/astro-ph/0310373

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