|| NGC 864 is a barred spiral galaxy in the direction of Cetus. It is
estimated to be around 69 million light years away. As a morphological
feature, bars in the centers of galaxies indicate a dynamic movement of
gas (and stars). While NGC 864 possesses a weak bar- the effects of the
stucture can be readily seen in the galaxy. Note the bottom picture of the
two at left. The elongated and extremely bright nucleus delineate the bar.
When displayed in a non-linear fashion (upper image) the delicate dust lanes
that run along the bar can be discerned. Galactic bars generally stir the
interiors of galaxies with flows of gas into and out of the region. Due to
their asymmetric concentration of mass, bars can also generate waves of
star formation in the outer disk by the oscillatory compression of gas. In the
case of NGC 864, the two major arms spring from the ends of the bar. These
arms indicate a continual emergence of new star-formation that continues
"downstream." A few other barred spirals include:
and many others.
|L R G B color production was used to create this image.||
Minimum credit line: Adam Block/NOAO/AURA/NSF
BACK to main Best of AOP page.
Return to NOAO Home Page