First results from the ESA’s Herschel Space Observatory were unveiled in December 2009, and the observatory in general – and the UK-led SPIRE instrument in particular – were performing well. Herschel uses the far-infrared and submillimetre part of the spectrum to pick out relatively cool dust and gas.
This demonstration image shows a region of star formation in the constellation of Aquila around 1000 light-years from Earth; the image is roughly 60 light-years across. The image is in false colour, with red showing light at 500 µm detected by SPIRE, while green and blue are light at 170 µm and 70 µm respectively, measured by PACS.
Large filaments of cold dust (seen as red and orange) thread through the region. The many blue regions are warmer, emitting more at shorter wavelengths, and show where the gas and dust is either collapsing under gravity to form stars, or where it has already collapsed and formed a protostar. There are hundreds of such regions within this image, which confirms the connection between the large, cool filaments and the places where stars form.
Prof. Derek Ward-Thompson, of Cardiff University and a member of the Gould Belt Key Project, for which this image was taken, said: “The insight into the way stars are forming that is provided by this image is absolutely fantastic, and I can’t wait to see the rest of the data we’re going to receive over the coming months.”
Other demonstration images show what Herschel can show about gas and dust in interacting galaxies such as the Virgo cluster and dwarf planets in the outer solar system.