Explanation:
This shock wave plows through space at over 500,000 kilometers per hour.
Moving right to left in the
beautifully
detailed
color composite, the thin, braided filaments are actually
long ripples in a sheet of glowing gas seen almost edge on.
Cataloged
as NGC 2736, its narrow appearance
suggests its popular name,
the Pencil Nebula.
About 5 light-years long and a mere 800 light-years away,
the Pencil Nebula is only a small part of the
Vela
supernova remnant.
The Vela remnant itself
is around 100 light-years in diameter, the expanding
debris
cloud of a star that was seen to
explode about 11,000 years ago.
Initially, the shock wave was moving at millions of kilometers
per hour but has slowed considerably, sweeping up
surrounding interstellar gas.
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