Picture of the Week

17 May 2010: That galaxies come in very different shapes and sizes is dramatically demonstrated by this striking Hubble image of the Hickson Compact Group 59. Named by astronomer Paul Hickson in 1982, this is the 59th such collection of galaxies in his catalogue of unusually close groups. What makes this image interesting is the variety on display. There are two large spiral galaxies, one face-on with smooth arms and delicate dust tendrils, and one highly inclined, as well as a strangely disorderly galaxy featuring clumps of blue young stars. We can also see many apparently smaller, probably more distant, galaxies visible in the background. Hickson groups display many peculiarities, often emitting in the radio and infrared and featuring active star-forming regions. In addition their galaxies frequently contain Active Galactic Nuclei powered by supermassive black holes, as well large quantities of dark matter. The NASA/ESA Hubble Space Telescope's Advanced Camera for Surveys, using …

10 May 2010: This striking Hubble image of the planetary nebula IC 4634 reveals two shining, S-shaped ejections from a dying star. This star, awash in glowing material at the centre of the picture, bloated as it aged and launched its outer layers off into space. The star’s very hot, exposed core has since beamed intense ultraviolet radiation at these lost shells of gas, making them glow in rich colours. This process has been far from orderly or calm, however, as revealed by the distinct, separate waves of thrown-off gases. One is more distant and therefore was spewed first, followed by a more recently ejected tide of matter that formed the tighter S-shape. The result is remarkably symmetric on each side of the central star. The NASA/ESA Hubble Space Telescope’s Wide Field Planetary Camera 2 (WFPC2) captured this image of IC 4634, which is found more than about 7500 light-years away in the …

3 May 2010: The richly textured spiral galaxy NGC 2082 is found about 60 million light-years away in the constellation of Dorado (the Swordfish), deep in the southern sky. As seen here in a very detailed image from the Advanced Camera for Surveys on the NASA/ESA Hubble Space Telescope, filaments of dark dust splay across NGC 2082’s luminous curved arms and dense central bulge of stars. Hubble’s sharp vision also reveals many of the individual bright blue stars dotting the galaxy’s rather ragged spiral arms as well as many much more distant galaxies in the background. This galaxy is faintly visible in backyard telescopes and was first recorded by Sir John Herschel during his visit to the Cape of Good Hope in South Africa in the 1830s. NGC 2082 was also the host of a bright supernova that was spotted by the great visual supernova discoverer Rev R. Evans back in 1992. This …

22 April 2010: As the first in the new weekly series of spectacular images from the NASA/ESA Hubble Space Telescope, the Hubble Picture of the Week, ESA/Hubble presents a stunning image of an unfamiliar star cluster. This rich collection of scattered stars, known as Messier 72, looks like a city seen from an airplane window at night, as small glints of light from suburban homes dot the outskirts of the bright city centre. Messier 72 is actually a globular cluster, an ancient spherical collection of old stars packed much closer together at its centre, like buildings in the heart of a city compared to less urban areas. As well as huge numbers of stars in the cluster itself the picture also captures the images of many much more distant galaxies seen between and around the cluster stars. French astronomer Pierre Méchain discovered this rich cluster in August of 1780, but we take Messier …