CO J = 3-2 and J = 2-1 observations of NGC 7027

Using the 15 m James Clerk Maxwell Telescope, the molecular envelope surrounding the planetary nebula NGC 7027 was mapped in the J=3-2 line of 12 CO and the central position in the J=3-2 line of 13 CO and the J=2-1 lines of 12 CO and 13 CO observed. The J=3-2 12 CO map shows substantial deviations from spherical symmetry. The mass-loss rate along the nebula's polar axis appears to be about half that in the equatorial directions. Bright line wings are caused by a bipolar flow of molecular gas along the low-density axis. This gas has an outflow velocity of 23 km/s, larger than the 15 km/s expansion velocity of the bulk of the envelope.