At the edge of the abyss: Fresh starbirth infuses the galaxy NGC 6503 with a vital pink glow in this image from the NASA/ESA Hubble Space Telescope. This galaxy, a smaller version of the Milky Way, is perched near a great void in space where few other galaxies reside. This new image from Hubble’s Advanced Camera for Surveys displays, with particular clarity, the pink-coloured puffs marking where stars have recently formed in NGC 6503's swirling spiral arms. Although structurally similar to the Milky Way, the disc of NGC 6503 spans just 30 000 light-years, or just about a third of the size of the Milky Way, leading astronomers to classify NGC 6503 as a dwarf spiral galaxy. NGC 6503 lies approximately 17 million light-years away in the constellation of Draco (the Dragon). The German astronomer Arthur Auwers discovered this galaxy in July 1854 in a region of space where few other luminous bodies have been found. NGC 6503 sits at the edge of a giant, hollowed-out region of space called the Local Void. The Hercules and Coma galaxy clusters, as well as our own Local Group of galaxies, circumscribe this vast, sparsely populated region. Estimates for the void’s diameter vary from 30 million to more than 150 million light-years — so NGC 6503 does not have a lot of galactic company in its immediate vicinity. The isolation of NGC 6503 inspired the stargazer Stephen James O'Meara to name it the Lost-In-Space Galaxy in his book Hidden Treasures. This Hubble image was created from exposures taken with the Wide Field Channel of the Advanced Camera for Surveys. The filters were unusual, which explains the peculiar colour balance of this picture. The red colouration derives from a 28-minute exposure through a filter that just allows the emission from hydrogen gas (F658N) to pass and which reveals the glowing clouds of gas associated with star-forming regions. This was combined with a 12-minute exposure through a near-infrared filter (F814W), which was coloured blue for contrast. The field of view is 3.3 by 1.8 arcminutes.

Name: NGC 6503
Type: Local Universe : Galaxy : Type : SpiralLocal Universe : Galaxy : Size : Dwarf
Category: Galaxies
Constellation: Draco
Distance: 17 million light years
Release date: 29 November 2010, 10:00
Credit: ESA/Hubble and NASA

Hubble peers deeply into the Eagle Nebula: The NASA/ESA Hubble Space Telescope has once more turned its attention towards the magnificent Eagle Nebula (Messier 16). This picture shows the northwestern part of the region, well away from the centre, and features some very bright young stars that formed from the same cloud of material. These energetic toddlers are part of an open cluster and emit ultraviolet radiation that causes the surrounding nebula to glow. The star cluster is very bright and was discovered in the mid-eighteenth century. The nebula, however, is much more elusive and it took almost a further two decades for it to be first noted by Charles Messier in 1764. Although it is commonly known as the Eagle Nebula, its official designation is Messier 16 and the cluster is also named NGC 6611. One spectacular area of the nebula (outside the field of view) has been nicknamed “The Pillars of Creation” ever since the Hubble Space Telescope captured an iconic image of dramatic pillars of star-forming gas and dust. The cluster and nebula are fascinating targets for small and medium-sized telescopes, particularly from a dark site free from light pollution. Messier 16 can be found within the constellation of Serpens Cauda (the Tail of the Serpent), which is sandwiched between Aquila, Sagittarius, and Ophiuchus in the heart of one of the brightest parts of the Milky Way. Small telescopes with low power are useful for observing large, but faint, swathes of the nebula, whereas 30 cm telescopes and larger may reveal the dark pillars under good conditions. But a space telescope in orbit around the Earth, like Hubble — which boasts a 2.4-metre diameter mirror and state-of-the-art instruments — is required for an image as spectacular as this one. This picture was created from images taken with the Wide Field Channel of Hubble’s Advanced Camera for Surveys. Images through a near-infrared filter (F775W) are coloured red and images through a blue filter (F475W) are blue. The exposures times were one hour and 54 minutes respectively and the field of view is about 3.3 arcminutes across.

Name: Messier 16, NGC 6611
Type: Milky Way : Nebula : Type : Star Formation
Category: Nebulae
Constellation: Serpens Cauda
Distance: 7000 light years
Release date: 6 December 2010, 10:00
Credit: ESA/Hubble & NASA

A dazzling planetary nebula: The NASA/ESA Hubble Space Telescope has turned its eagle eye to the planetary nebula NGC 6572, a very bright example of these strange but beautiful objects. Planetary nebulae are created during the late stages of the evolution of certain stars that eject gas into space and emit intense ultraviolet radiation that makes the material glow. This picture of NGC 6572 shows the intricate shapes that can develop as stars exhale their last breaths. Hubble has even imaged the central white dwarf star, the origin of the dazzling nebula, but now a faint, but hot, vestige of its former glory. NGC 6572 only began to shed its gases a few thousand years ago, so it is a fairly young planetary nebula. As a result the material is still quite concentrated, which explains why it is abnormally bright. The envelope of gas is currently racing out into space at a speed of around 15 kilometres every second and as it becomes more diffuse, it will dim. NGC 6572 was discovered in 1825 by the German astronomer Friedrich Georg Wilhelm von Struve, who came from a family of distinguished stargazers. The name planetary nebula is left over from the time when the telescopes of early astronomers were not good enough to reveal the true nature of these objects. To many, the discs looked like the outer planets Uranus and Neptune. The application of spectral analysis, later in the 19th century, first revealed that they were glowing gas clouds. NGC 6572 is magnitude 8.1, easily bright enough to make it an appealing target for amateur astronomers with telescopes. It is located within the large constellation of Ophiuchus (the Serpent Bearer) and at low magnification it will appear to be just a coloured star, but higher magnification will reveal its shape. Some observers report that NGC 6572 looks blue, while others state that it is green. Colour as seen through the eyepiece is often a matter of interpretation, so you may make your own decision! This picture was created from images taken with Hubble’s Wide Field Camera 2. Images through a blue filter that isolates the glow from hydrogen gas (Hβ, F487N, coloured dark blue), a green filter that isolates emission from ionised oxygen (F502N, coloured blue), a yellow broadband filter (F555W, coloured green) and a red filter that passes emission from hydrogen (Hα, F656N) have been combined. The exposure times were 360 s, 240 s, 100 s and 180 s, respectively and the field of view is just 29 arcseconds across.

Name: NGC 6572
Type: Milky Way : Nebula : Type : Planetary
Category: Nebulae
Constellation: Ophiuchus
Distance: 3500 light years
Release date: 13 December 2010, 10:00
Credit: ESA/Hubble & NASA