Explanation:
How did the star Eta Carinae create this unusual nebula?
No one knows for sure.
About 165 years ago, the southern star
Eta Carinae
mysteriously became the second
brightest star in the night sky.
In 20 years, after ejecting more mass than our Sun, Eta Car unexpected faded.
This outburst appears to have created the
Homunculus Nebula,
pictured above in a composite image from the
Hubble Space Telescope
taken last decade.
Visible in the
above image
center is purple-tinted light reflected from the violent star Eta Carinae itself.
Surrounding this star are expanding lobes of gas laced with filaments of dark
dust.
Jets bisect the lobes emanating from the central star.
Surrounding these lobes are
red-tinted debris
captured only by its glow in a narrow band of red light.
This debris is expanding most quickly of all, and includes streaming
whiskers and
bow shocks caused by collisions with
previously existing material.
Eta Car still undergoes
unexpected outbursts,
and its high mass and volatility make it a candidate to explode in a
spectacular supernova
sometime in the next few million years.
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