The
Circinus Galaxy was discovered relatively recently as it hides behind the
bright stellar disk of the Milky Way. The color composite image shows the cold
neutral hydrogen gas in blue, warm dust
in red, and stars in green. It highlights
the disk and inner spiral arms of the Circinus Galaxy; its hydrogen envelope
extends well beyond the image shown here. The Spitzer Space Telescope was used
to map Circinus in the infrared at wavelength of 3.6 and 8 micron, while the
21-cm spectral line of hydrogen (HI) was mapped with the Australia Telescope
Compact Array in Narrabri (published by For, Koribalski & Jarrett 2012). Hydrogen is the
fuel for star formation and a tracer for dark matter in galaxies. - My one
minute lightning talk at Sydney's Vivid Festival featured this image, recounted
in the CSIRO
Universe Blog.
|