PHOTO NO.: STScI-PRC99-23


A BUTTERFLY-SHAPED "PAPILLON" NEBULA YIELDS SECRETS OF MASSIVE STAR
BIRTH

A NASA Hubble Space Telescope view of a turbulent cauldron of
starbirth, called N159, taking place 170,000 light-years away in our
satellite galaxy, the Large Magellanic Cloud (LMC). Torrential stellar
winds from hot newborn massive stars within the nebula sculpt ridges,
arcs, and filaments in the vast cloud, which is over 150 light-years
across.

A rare type of compact ionized "blob" is resolved for the first time to
be a butterfly-shaped or "Papillon" (French for "butterfly") nebula,
buried in the center of the maelstrom of glowing gases and dark dust.
The unprecedented details of the structure of the Papillon, itself less
than 2 light-years in size (about 2 arcseconds in the sky), are seen in
the inset.

A possible explanation of this bipolar shape is the outflow of gas
from massive stars (over 10 times the mass of our sun) hidden in the
central absorption zone. Such stars are so hot that their radiation
pressure halts the infall of gas and directs it away from the stars in
two opposite directions.  Presumably, a dense equatorial disk formed by
matter still trying to fall in onto the stars focuses the outstreaming
matter into the bipolar directions.

This observation is part of a search for young massive stars in the 
LMC. Rare are the cases where we can see massive stars so early 
after their birth.

The red in this true-color image is from the emission of hydrogen and
the yellow from high excitation ionized oxygen. The picture was taken
on September 5, 1998 with the Wide Field Planetary Camera 2.

The Hubble observations of the Papillon nebula were conducted by the
European astronomers Mohammad Heydari-Malayeri (Paris Observatory,
France) and co-investigators Michael Rosa (Space Telescope-European
Coordinating Facility, European Southern Observatory, Germany),
Vassilis Charmandaris (Paris Observatory), Lise Deharveng (Marseille
Observatory, France), and Hans Zinnecker (Astrophysical Institute, 
Potsdam, Germany).

Their work is submitted for publication in the European journal 
Astronomy and Astrophysics. 

Credit: M. Heydari-Malayeri (Paris Observatory) and NASA/ESA