The Wasp-Waist Nebula: VLA NH3 Observations of the Molecular Core
Envelope in a Unique Class 0 Protostellar System
Jennifer Wiseman (GSFC), Mary Barsony (SSI & SFSU), & Raghvendra Sahai (JPL)
The Wasp-Waist Nebula’s
dramatic bipolar, hourglass shape, seen in light
scattered off of the cavity
walls excavated by the
outflow, is evident in the
Spitzer IRAC image above
(courtesy of D.
Ciardi/Caltech).
Integrated NH3(1,1) emission of the
dense, protostellar envelope’s gas, as
mapped with the VLA. Contour levels
begin at 16 mJy/beam•km s-1, and
increase by steps of 16 mJy/beam•km s-1
A unique characteristic
of this isolated
protostar is that its
infall envelope is
readily visible in
absorption against the
PAH emission of the
cloud, as seen in the
Spitzer IRAC 8.0 mm
image above.
Contours of the
NH3(1,1) emission
detected by the VLA
are overlaid. The
resemblance of the
mophology of the gas
emission to the dust
absorption of the
envelope is striking.
Spitzer IRS (Infrared
Spectrometer) scanmapping of the
central 2.25' x 1' of
the Wasp-Waist
Nebula reveals the Sshaped outflow in the
lowest rotational
transitions of the H2
molecule [1], as
distinct from the
bipolar cavity, seen in
scattered light, and
so evident in the
IRAC images.
Contours of the
NH3(1,1) emission
detected by the VLA
are overlaid, and
show how the
envelope gas cradles
the outflow cavities.
Background Image Credit: J. Wiseman