The Nearby Milky Way in Cold Dust
What shapes the remarkable dust tapestry of the nearby Milky Way Galaxy?
No one knows for sure.
The intricate structures, shown above,
were resolved in new detail recently in a wide region of the sky imaged in far infrared light by the
European Space Agency's
Planck satellite.
The above image is a digital fusion of three infrared colors: two taken at high resolution by Planck, while the other is an
older image taken by the now defunct
IRAS satellite.
At these colors, the sky is dominated by the faint
glow of very cold gas within only 500
light years of Earth.
In the above image, red corresponds to temperatures as cold as 10 degrees
Kelvin above absolute zero, while white corresponds to gas as warm at 40 Kelvins.
The pink band across the lower part of the image is warm gas confined to the
plane of our Galaxy.
The bright regions typically hold dense
molecular clouds that are
slowly collapsing to form stars,
whereas the dimmer regions are most usually
diffuse interstellar gas and
dust known as
cirrus.
Why these regions have
intricate filamentary shapes shared on both large and small scales remains a topic of research.
Future study of the origin and evolution of dust may help in the understanding the
recent history of our Galaxy as well as how
planetary systems
such as our Solar System
came to be born.