Glowing, fiery shells of gas: It may look like something from The Lord of the Rings, but this fiery swirl  is actually a planetary nebula known as ESO 456-67. Set against a  backdrop of bright stars, the rust-coloured object lies in the  constellation of Sagittarius (The Archer), in the southern sky. Despite  the name, these ethereal objects have nothing at all to do with  planets; this misnomer came about over a century ago, when the first  astronomers to observe them only had small, poor-quality telescopes.  Through these, the nebulae looked small, compact, and planet-like — and  so were labelled as such. When  a star like the Sun approaches the end of its life, it flings material  out into space. Planetary nebulae are the intricate, glowing shells of  dust and gas pushed outwards from such a star. At their centres lie the  remnants of the original stars themselves — small, dense white dwarf  stars. In  this image of ESO 456-67, it is possible to see the various layers of  material expelled by the central star. Each appears in a different hue —  red, orange, yellow, and green-tinted bands  of gas are visible, with clear patches of space at the heart of the  nebula. It is not fully understood how planetary nebulae form such a  wide variety of shapes and structures; some appear to be spherical, some  elliptical, others shoot material in waves from their polar regions,  some look like hourglasses or figures of eight, and others resemble  large, messy stellar explosions — to name but a few. A version of this image was entered into the Hubble's Hidden Treasures image processing competition by contestant Jean-Christophe Lambry

Name: ESO 456-67
Type: Milky Way : Nebula : Type : Planetary
Category: Nebulae
Constellation: Sagittarius
Release date: 25 February 2013, 10:00
Credit: ESA/Hubble & NASAAcknowledgement: Jean-Christophe Lambry

Blue bursts of hot young stars: This  image, speckled with blue, white, and yellow light, shows part of the  spiral galaxy IC 5052. Surrounded by distant stars and galaxies, it  emits a bright blue-white glow which highlights its narrow, intricate  structure. It is viewed side-on in the constellation of Pavo (The  Peacock), in the southern sky. When  spiral galaxies are viewed from this angle, it is very difficult to  fully understand their properties and how they are arranged. IC 5052 is  actually a barred spiral galaxy – its pinwheeling arms do not begin from  the centre point but are instead attached to either end of a straight  "bar" of stars that cuts through the galaxy's middle. Approximately two  thirds of all spirals are barred, including the Milky Way. Bursts  of pale blue light are visible across the galaxy's length, partially  blocked out by weaving lanes of darker gas and dust. These are pockets  of extremely hot newborn stars. The bars present in spirals like IC 5052  are thought to help these formation processes by effectively funnelling  material from the swirling arms inwards towards these hot stellar  nurseries. A version of this image was submitted to the Hubble's Hidden Treasures image processing competition by contestant Serge Meunier.

Name: IC 5052
Type: Local Universe : Galaxy : Type : Spiral
Category: Galaxies
Constellation: Pavo
Distance: 25 million light years
Release date: 4 March 2013, 10:00
Credit: ESA/Hubble & NASA Acknowledgement: S. Meunier

One ring to rule them all: Galaxies  can take many forms — elliptical blobs, swirling spiral arms, bulges,  and discs are all known components of the wide range of galaxies we have  observed using telescopes like the NASA/ESA Hubble Space Telescope.  However, some of the more intriguing objects in the sky around us  include ring galaxies like the one pictured above — Zw II 28. Ring  galaxies are mysterious objects. They are thought to form when one  galaxy slices through the disc of another, larger, one — as galaxies are  mostly empty space, this collision is not as aggressive or as  destructive as one might imagine. The likelihood of two stars physically  colliding is minimal, and it is instead the gravitational effects of  the two galaxies that causes the disruption. This  disruption upsets the material in both galaxies, causing it to  redistribute to form a dense central core, encircled by bright stars.  All this commotion causes clouds of gas and dust to collapse and  triggers new periods of intense star formation in the outer ring, which  is thus full of hot, young, blue stars and regions that are actively  giving rise to new stars. The  sparkling pink and purple loop of Zw II 28 is not a typical ring  galaxy due to its lack of a visible central companion. For many years it  was thought to be a lone circle on the sky, but observations using  Hubble have shown that there may be a possible companion lurking just  inside the ring, where the loop appears to double back on itself. The  galaxy has a knotty, swirling ring structure, with some areas appearing  much brighter than others. A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

Name: II Zw 28, VV 790b
Type: Local Universe : Galaxy : Type : Ring
Category: Galaxies
Constellation: Orion
Distance: z=0.028 (redshift)
Release date: 11 March 2013, 10:00
Credit: ESA/Hubble & NASAAcknowledgement: Judy Schmidt

Galactic glow worm: This  charming and bright galaxy, known as IRAS 23436+5257, was captured by  the the NASA/ESA Hubble Space Telescope. It is located in the northern  constellation of Cassiopeia, which is named after an arrogant, vain, and  yet beautiful mythical queen. The  twisted, wormlike structure of this galaxy is most likely the result of  a collision and subsequent merger of two galaxies. Such interactions  are quite common in the Universe, and they can range from minor  interactions involving a satellite galaxy being caught by a spiral arm,  to major galactic crashes. Friction between the gas and dust during a  collision can have a major effect on the galaxies involved, morphing the  shape of the original galaxies and creating interesting new structures. When  you look up at the calm and quiet night sky it is not always easy to  picture it as a dynamic and vibrant environment with entire galaxies in  motion, spinning like children’s toys and crashing into whatever crosses  their path. The motions are, of course, extremely slow, and occur over  millions or even billions of years. The  aftermath of these galactic collisions helps scientists to understand  how these movements occur and what may be in store for our own Milky Way, which is on a collision course with a neighbouring  galaxy, Messier 31. A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt. Hidden Treasures was an initiative to  invite astronomy enthusiasts to search the Hubble archive for stunning  images that have never been seen by the general public. The competition  has now closed and the results are published here.

Name: IRAS 23436+5257
Type: Local Universe : Galaxy : Type : SpiralLocal Universe : Galaxy : Type : Interacting
Category: Galaxies
Constellation: Cassiopeia
Distance: z=0.034 (redshift)
Release date: 18 March 2013, 10:00
Credit: ESA/Hubble & NASAAcknowledgement: Judy Schmidt