Zeta Oph: Runaway Star
From NASA’s Astronomy Picture of the Day
From NASA’s Astronomy Picture of the Day
Like a ship plowing
through cosmic seas, runaway
star Zeta Ophiuchi produces the arcing interstellar bow wave or bow
shock seen in this stunning
infrared portrait.
In the false-color view,
bluish Zeta Oph, a star about 20 times more massive than the Sun, lies near the
center of the frame, moving toward the left at 24 kilometers per second.
Its strong stellar wind
precedes it, compressing and heating the dusty interstellar material and
shaping the curved shock front. Around it are clouds of relatively undisturbed
material.
What set this star in
motion? Zeta Oph was likely once a member of a binary star system, its
companion star was more massive and hence shorter
lived. When the companion exploded as a supernova catastrophically
losing mass, Zeta Oph was flung out of the system.
About 460 light-years
away, Zeta Oph is 65,000 times more luminous than the Sun and would be one of
the brighter stars in the sky if it weren't surrounded by obscuring dust. The
image spans about 1.5 degrees or 12 light-years at the estimated distance of Zeta Ophiuchi.
