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Barred Spiral Galaxy Swirls in the Night Sky January 24, 2012

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Barred Spiral Galaxy Swirls in the Night Sky

Description:

This image shows the swirling shape of galaxy NGC 2217, in the constellation of Canis Major (The Great Dog). In the central region of the galaxy is a distinctive bar of stars within an oval ring. Further out, a set of tightly wound spiral arms almost form a circular ring around the galaxy. NGC 2217 is therefore classified as a barred spiral galaxy, and its circular appearance indicates that we see it nearly face-on.

The outer spiral arms have a bluish colour, indicating the presence of hot, luminous, young stars, born out of clouds of interstellar gas. The central bulge and bar are yellower in appearance, due to the presence of older stars. Dark streaks can also be seen in places against the galaxy’s arms and central bulge, where lanes of cosmic dust block out some of the starlight.

The majority of spiral galaxies in the local Universe — including our own Milky Way — are thought to have a bar of some kind, and these structures play an important role in the development of a galaxy. They can, for example, funnel gas towards the centre of the galaxy, helping to feed a central black hole, or to form new stars.

Credit:

ESO

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Orion in a New Light February 12, 2010

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Description:

The Orion Nebula reveals many of its hidden secrets in a dramatic image taken by ESO’s new VISTA survey telescope. The telescope’s huge field of view can show the full splendour of the whole nebula and VISTA’s infrared vision also allows it to peer deeply into dusty regions that are normally hidden and expose the curious behaviour of the very active young stars buried there.

VISTA — the Visible and Infrared Survey Telescope for Astronomy — is the latest addition to ESO’s Paranal Observatory (eso0949). It is the largest survey telescope in the world and is dedicated to mapping the sky at infrared wavelengths. The large (4.1-metre) mirror, wide field of view and very sensitive detectors make VISTA a unique instrument. This dramatic new image of the Orion Nebula illustrates VISTA’s remarkable powers.

The Orion Nebula is a vast stellar nursery lying about 1350 light-years from Earth. Although the nebula is spectacular when seen through an ordinary telescope, what can be seen using visible light is only a small part of a cloud of gas in which stars are forming. Most of the action is deeply embedded in dust clouds and to see what is really happening astronomers need to use telescopes with detectors sensitive to the longer wavelength radiation that can penetrate the dust. VISTA has imaged the Orion Nebula at wavelengths about twice as long as can be detected by the human eye.

As in the many visible light pictures of this object, the new wide field VISTA image shows the familiar bat-like form of the nebula in the centre of the picture as well as the fascinating surrounding area. At the very heart of this region lie the four bright stars forming the Trapezium, a group of very hot young stars pumping out fierce ultraviolet radiation that is clearing the surrounding region and making the gas glow. However, observing in the infrared allows VISTA to reveal many other young stars in this central region that cannot be seen in visible light.

Looking to the region above the centre of the picture, curious red features appear that are completely invisible except in the infrared. Many of these are very young stars that are still growing and are seen through the dusty clouds from which they form. These youthful stars eject streams of gas with typical speeds of 700 000 km/hour and many of the red features highlight the places where these gas streams collide with the surrounding gas, causing emission from excited molecules and atoms in the gas. There are also a few faint, red features below the Orion Nebula in the image, showing that stars form there too, but with much less vigour. These strange features are of great interest to astronomers studying the birth and youth of stars.

This new image shows the power of the VISTA telescope to image wide areas of sky quickly and deeply in the near-infrared part of the spectrum. The telescope is just starting to survey the sky and astronomers are anticipating a rich harvest of science from this unique ESO facility.

Credits:

European Southern Observatory, Paranal Observatory

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PSR J0108-1431: Geriatric Pulsar Still Kicking March 10, 2009

Posted by jtintle in Deep Space, Space Fotos.
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PSR J0108-1431
Credit:

X-ray: NASA/CXC/Penn State/G.Pavlov et al.; Optical: ESO/VLT/UCL/R.Mignani et al.; Illustration: NASA/CXC/M.Weiss.

Description:

The composite image on the left shows an image from NASA’s Chandra X-ray Observatory in purple and an optical image from the European Southern Observatory’s Very Large Telescope (VLT) in red, blue and white. The Chandra source in the center of the image is the ancient pulsar PSR J0108-1431 (J0108 for short), located only 770 light years from us. The elongated object immediately to its upper right is a background galaxy that is unrelated to the pulsar. Since J0108 is located a long way from the plane of our galaxy, many distant galaxies are visible in the larger-scale optical image.
The position of the pulsar seen by Chandra in this image from early 2007 is slightly different from the radio position observed in early 2001, implying that the pulsar is moving at a velocity of about 440,000 miles per hour, in the direction shown by the white arrow. The detection of this motion allowed an estimate of where J0108 should be located in the VLT image taken in 2000. The faint blue star just above the galaxy is a possible optical detection of the pulsar.

The artist’s impression on the right shows what J0108 might look like if viewed up close. Radiation from particles spiraling around magnetic fields is shown along with heated areas around the neutron star’s magnetic poles. Both of these effects are expected to generate X-ray emission. Most of the surface of the neutron star is expected to be too cool to produce X-rays, but it should produce optical and ultraviolet radiation. Thus, multiwavelength observations are important for providing a complete picture of these exotic objects.

At an age of about 200 million years, this pulsar is the oldest isolated pulsar ever detected in X-rays. Among isolated pulsars – ones that have not been spun-up in a binary system – it is over 10 times older than the previous record holder with an X-ray detection. This pulsar is slowing down as it ages and converting some of the energy that is being lost into X-rays. The efficiency of this process for J0108 is found to be higher than for any other known pulsar.

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Orion Nebula: The Hubble View March 10, 2009

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See Explanation.  Clicking on the picture will download  the highest resolution version available.

Credit:

NASA, ESA, M. Robberto (STScI/ESA) et al.

Description:

Few cosmic vistas excite the imagination like the Orion Nebula. Also known as M42, the nebula’s glowing gas surrounds hot young stars at the edge of an immense interstellar molecular cloud only 1,500 light-years away. The Orion Nebula offers one of the best opportunities to study how stars are born partly because it is the nearest large star-forming region, but also because the nebula’s energetic stars have blown away obscuring gas and dust clouds that would otherwise block our view – providing an intimate look at a range of ongoing stages of starbirth and evolution. This detailed image of the Orion Nebula is the sharpest ever, constructed using data from the Hubble Space Telescope‘s Advanced Camera for Surveys and the European Southern Observatory’s La Silla 2.2 meter telescope. The mosaic contains a billion pixels at full resolution and reveals about 3,000 stars.

M83: The Thousand-Ruby Galaxy September 28, 2008

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See Explanation.  Clicking on the picture will download  the highest resolution version available.

Color Composite:

Davide De Martin (Skyfactory)

Credit:

European Southern Observatory Science Archive

Explanation:

Big, bright, and beautiful, spiral galaxy M83 lies a mere twelve million light-years away, near the southeastern tip of the very long constellation Hydra. Prominent spiral arms traced by dark dust lanes and blue star clusters lend this galaxy its popular name of the Southern Pinwheel. But reddish star forming regions that dot the sweeping arms highlighted in this sparkling color composite also suggest another nickname, The Thousand-Ruby Galaxy. About 40,000 light-years across, M83 is a member of a group of galaxies that includes active galaxy Centaurus A. The core of M83 itself is bright at x-ray energies, showing a high concentration of neutron stars and black holes left from an intense burst of star formation. The sharp image, based on archival data from the European Southern Observatory’s Wide Field Imager camera, also features spiky foreground Milky Way stars and distant background galaxies.

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