IC4634’s Glowing Waves: 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 constellation of Ophiuchus (the Serpent Holder). IC 4634 and other objects like it are known as planetary nebulae due to their appearance through early telescopes as rounded, faintly luminous discs similar to the distant planets Uranus and Neptune. The picture was created from images through five different filters (F487N, F502N, F574M, F656N and F658N) that captured light emitted by different elements in the gaseous features. The total aggregate exposure time was 4000 seconds and the field of view is just 29 arcseconds across.

Name: IC 4634
Type: Milky Way : Nebula : Type : Planetary
Category: Nebulae
Constellation: Ophiuchus
Distance: 7500 light years
Release date: 10 May 2010, 10:00
Credit: ESA/Hubble and NASA.

A clump of galaxy misfits: 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 the Wide Field Channel, captured this image of HCG059 in 2007. The picture was created from images taken through blue, yellow and near-infrared filters (F435W, F606W and F814W). The total exposure times per filter were 57 minutes, 41 minutes and 35 minutes respectively. The field of view is about 3.4 arcminutes across.

Name: HCG 59
Type: Local Universe : Galaxy : Grouping : Multiple
Category: Galaxies
Constellation: Leo
Distance: 180 million light years
Release date: 17 May 2010, 10:00
Credit: ESA/Hubble and NASA

Hubble on the face of the Sun: This remarkable and unique image of the space shuttle Atlantis and the NASA/ESA Hubble Space Telescope silhouetted against the dazzling disc of the Sun was captured from the ground near the start of the Servicing Mission 4 on 13 May 2009. The picture was taken from Florida, 100 kilometres south of the Kennedy Space Center as Hubble was about to be grappled by the Shuttle’s robot arm. The Shuttle and Hubble appear as small black specks at the lower left, the Shuttle is the larger of the two. The solar disc was unusually quiet in a deep solar minimum and there are no sunspots visible. The image was acquired with a 130 mm aperture refracting telescope equipped with a special solar prism to reduce the intensity along with a standard digital camera. The transit across the disc of the Sun took less than one second and the path across the ground where it could be observed was only a few kilometres wide — giving some idea of the extraordinarily careful planning needed.

Name: Atlantis Space Shuttle, Sun
Type: Solar System : StarSolar System : Technology : Spacecraft : Orbiter
Category: Solar System
Release date: 24 May 2010, 10:00
Credit: Thierry Legault/NASA (www.astrophoto.fr)

NGC 3810: A picture-perfect spiral: The bright galaxy NGC 3810 demonstrates classical spiral structure in this very detailed image from Hubble. The bright central region is thought to be forming many new stars and is outshining the outer areas of the galaxy by some margin. Further out the galaxy displays strikingly rich dust clouds along its spiral arms. A close look shows that Hubble’s sharp vision also allows many individual stars to be seen. Hot young blue stars show up in giant clusters far from the centre and the arms are also littered with bright red giant stars. The original images were acquired by astronomers studying a supernova discovered late in the year 2000. It was the second supernova found in the galaxy in quick succession following another discovered in 1997. NGC 3810 is located about 50 million light-years from Earth in the constellation of Leo (the lion). It was discovered by William Herschel in 1784 and is easily seen as a faint smudge in small telescopes. The NASA/ESA Hubble Space Telescope's Advanced Camera for Surveys captured this image of NGC 3810. It was observed through three filters letting through blue, green and near-infrared list respectively (F435W, F555W and F814W). The exposure times were about seven minutes per filter and the field of view is about 3.4 x 1.7 arcminutes.

Name: NGC 3810
Type: Local Universe : Galaxy : Activity : Starburst
Category: Galaxies
Constellation: Leo
Distance: 50 million light years
Release date: 31 May 2010, 10:00
Credit: ESA/Hubble and NASA

The unique Red Rectangle: sharper than ever before: The star HD 44179 is surrounded by an extraordinary structure known as the Red Rectangle. It acquired its moniker because of its shape and its apparent colour when seen in early images from Earth. This strikingly detailed new Hubble image reveals how, when seen from space, the nebula, rather than being rectangular, is shaped like an X with additional complex structures of spaced lines of glowing gas, a little like the rungs of a ladder. The star at the centre is similar to the Sun, but at the end of its lifetime, pumping out gas and other material to make the nebula, and giving it the distinctive shape. It also appears that the star is a close binary that is surrounded by a dense torus of dust — both of which may help to explain the very curious shape. Precisely how the central engine of this remarkable and unique object spun the gossamer threads of nebulosity remains mysterious. It is likely that precessing jets of material played a role. The Red Rectangle is an unusual example of what is known as a proto-planetary nebula. These are old stars, on their way to becoming planetary nebulae. Once the expulsion of mass is complete a very hot white dwarf star will remain and its brilliant ultraviolet radiation will cause the surrounding gas to glow. The Red Rectangle is found about 2 300 light-years away in the constellation Monoceros (the Unicorn). The High Resolution Channel of the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys captured this view of HD 44179 and the surrounding Red Rectangle nebula — the sharpest view so far. Red light from glowing Hydrogen was captured through the F658N filter and coloured red. Orange-red light over a wider range of wavelengths through a F625W filter was coloured blue. The field of view is about 25 by 20 arcseconds.

Name: HD 44179
Type: Milky Way : Nebula : Type : Planetary
Category: Stars
Constellation: Monoceros
Distance: 2300 light years
Release date: 7 June 2010, 10:00
Credit: ESA/Hubble and NASA