This dazzling infrared image from NASA's Spitzer Space Telescope shows
hundreds of thousands of stars crowded into the swirling core of our
spiral Milky Way galaxy. In visible-light pictures, this region cannot
be seen at all because dust lying between Earth and the galactic center
blocks our view.
In this false-color picture, old and cool stars are blue, while dust
features lit up by blazing hot, massive stars are shown in a reddish hue.
Both bright and dark filamentary clouds can be seen, many of which harbor
stellar nurseries. The plane of the Milky Way's flat disk is apparent as
the main, horizontal band of clouds. The brightest white spot in the
middle is the very center of the galaxy, which also marks the site of a
supermassive black hole.
The region pictured here is immense, with a horizontal span of 890
light-years and a vertical span of 640 light-years. Earth is located
26,000 light-years away, out in one of the Milky Way's spiral arms.
Though most of the objects seen in this image are located at the galactic
center, the features above and below the galactic plane tend to lie closer
to Earth.
Scientists are intrigued by the giant lobes of dust extending away from
the plane of the galaxy. They believe the lobes may have been formed by
winds from massive stars.
This image is a mosaic of thousands of short exposures taken by Spitzer's
infrared array camera, showing emissions from wavelengths of 3.6 microns
(blue), 4.5 microns (green), 5.8 microns (orange), and 8.0 microns (red).
The entire region was imaged in less than 16 hours.