By Paul Rincon

Science reporter, BBC News, Plymouth



The composite image shows the Whirlpool Galaxy, known as M51

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The European Space Agency (Esa) has released a stunning image of the spiral galaxy M51, otherwise known as the Whirlpool Galaxy.

It is a composite of images taken by Europe's Herschel space observatory and the Hubble Space Telescope.

The picture combines views of the galaxy captured at visible and far-infrared wavelengths.

It highlights the cool, dusty and gaseous regions of M51, where the process of star formation is underway.

Professor David Southwood, director of science and robotic exploration at Esa, commented: "It's a wonderful image. It gives you some sense of the resolution we're going to get (with the Herschel telescope).

"The red areas are those we have detected where we know star formation is going on. We're seeing the birth of stars already."

Launched into space on 14 May, Herschel is still in its commissioning phase.

Herschel's full wavelength range spans 55 to 672 microns. Observations at longer wavelengths do not produce images with resolutions as high as those obtained at shorter wavelengths, such as the visible light detected by Hubble.

However, Herschel's mirror is the largest infrared astronomy mirror ever launched into space, so it can take the sharpest pictures to date at the wavelengths it observes. And astronomers need to view objects at a range of wavelengths to get a full understanding of the processes taking place in those phenomena.

Herschel and Hubble make a powerful combination.

The Whirlpool Galaxy lies relatively nearby, about 35 million light-years away in the constellation Canes Venatici.

Paul.Rincon-INTERNET@bbc.co.uk