Bibcode
DOI
Guerrero, M. A.; Vázquez, R.; López, J. A.
Referencia bibliográfica
The Astronomical Journal, Volume 117, Issue 2, pp. 967-973.
Fecha de publicación:
2
1999
Número de citas
36
Número de citas referidas
19
Descripción
Four planetary nebulae (PNe) with conspicuous point-symmetric morphology
are studied in this paper through high-quality imagery and long-slit
echelle spectroscopy. Point symmetry is also found in the velocity
space, and this is related to particular forms of bipolar collimated
outflows. Morphology and kinematics together reveal the presence of
collimated bipolar ejections in an episodic way with indications of
rotation or displacement of the symmetry axis of the outflow. Point
symmetry is currently known to occur in a wide variety of PNe and the
convenience of a reevaluation of point-symmetric PNe as a main
morphological class is pointed out.