Image Data: Subaru Telescope (NAOJ), Hubble Space Telescope,
Additional Color Data and Processing: Robert Gendler
Explanation: South of the large star-forming region known as the Orion
Nebula, lies bright blue reflection nebula NGC 1999. At the edge
of the Orion molecular
cloud complex some 1,500 light-years distant, NGC 1999's illumination is
provided by the embedded variable star V380 Orionis. That nebula is marked with
a dark sideways T-shape near center in this cosmic
vista that spans about 10 light-years. The dark shape was once assumed to be
an obscuring dust cloud seen in silhouette against the bright reflection nebula.
But recent infrared
images indicate the shape is likely a hole blown through the nebula itself
by energetic young stars. In fact, this region
abounds with energetic young stars producing jets and outflows with luminous
shock waves. Cataloged as Herbig-Haro (HH) objects, named for astronomers George
Herbig and Guillermo Haro, the shocks look like red gashes in this scene that
includes HH1 and HH2 just below NGC 1999. The stellar
jets push through the surrounding material at speeds of hundreds of
kilometers per second.
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