1. Hubble travelled 3.4 billion miles, circling Earth nearly 137,000 times and making more than 1.2 million observations of more than 38,000 celestial objects. Relax and enjoy Hubble 25, voted the best 25 images.

2. This is a giant cluster of about 3,000 stars called Westerlund 2  The cluster resides in a raucous stellar breeding ground known as Gum 29, located light-years away in the constellation Carina.

3. It is a reflection nebula in the constellation Orion
It is a reflection nebula in the constellation Orion. Like fog around a street lamp, a reflection nebula shines only because the light from an embedded source illuminates its dust; the nebula does not emit any visible light of its own.

4. Spectacular jets are powered by the gravitational energy of a super-massive black hole in the core of the elliptical galaxy Hercules A. The jets are very-high-energy plasma beams, subatomic particles and magnetic fields shot at nearly the speed of light.

5. This is Cassiopeia A, the youngest known remnant from a supernova explosion in the Milky Way. A supernova is the explosive demise of a massive star that collapses under the weight of its own gravity. The collapsed star then blows its outer layers into space.

6. This Hubble telescope snapshot of MyCn18, a young planetary nebula, reveals that the object has an hourglass shape with an intricate pattern of "etchings" in its walls. A planetary nebula is the glowing relic of a dying, Sun-like star.

7. The Engraved Hourglass Nebula (also known as MyCn 18) is a young planetary nebula situated in the southern constellationMusca about 8,000 light-years away from Earth.

8. A very small, faint galaxy was discovered at a tremendous distance of 13.4 billion light-years (consider that the universe is estimated to be 14 billion years old). 

9. Dubbed the Spirograph Nebula, IC 418 shows patterns that are not well understood. They may be related to chaotic winds from the variable central star, which changes brightness unpredictably

10. The disk galaxy NGC 5866 is viewed tilted nearly edge-on to our line of sight. Viewed face on, it would look like a smooth, flat disc with little spiral structure.

11. Stephan's Quintet is a group of five galaxies
Stephan's Quintet is a group of five galaxies. Three of the galaxies have distorted shapes, elongated spiral arms, and long, gaseous tidal tails containing myriad star clusters. These interactions have sparked a frenzy of star birth in the central pair of galaxies.

12. This turbulent cosmic pinnacle lies within a stellar nursery called the Carina Nebula, located 7,500 light-years away in the constellation Carina. Note the three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby bright stars. 

13. This Hubble image of supernova remnant 0509-67
This Hubble image of supernova remnant shows soft green and blue hues of heated material surrounded by a glowing pink shell, which shows the ambient gas being shocked by the expanding blast wave from the supernova.

14. NGC 6302 has ejected its envelope of gases and is now unleashing a stream of ultraviolet radiation that is making the cast-off material glow. This object is an example of a planetary nebula.

15. The towering pillars are about five light-years tall and are bathed in the blistering ultraviolet light from a grouping of young, massive stars located off the top of the image. Streamers of gas can be seen bleeding off the pillars as the intense radiation heats.

16. NGC 5189 shows a dying star expelling a large portion of its outer envelope. This material then becomes heated by the radiation from the stellar remnant and radiates, producing glowing clouds of gas.
The central star now lives its final days as a white dwarf.

17. Hubble photographed a group of interacting galaxies called Arp 273
Hubble photographed a group of interacting galaxies called Arp 273. The larger of the spiral galaxies, known as UGC 1810, has a disk that is distorted into a rose-like shape by the gravitational tidal pull of the companion galaxy below it, known as UGC 1813.

18. This giant spiral disc of stars, dust, and gas is 170,000 light-years across or nearly twice the diameter of the Milky Way. The Pinwheel Galaxy, M101 is estimated to contain at least one trillion stars.

19. A bull's eye pattern of eleven or more concentric rings, or shells, surround the Cat's Eye Nebula. Each 'ring' is the edge of a spherical bubble seen projected onto the sky. Observations suggest the star ejected its mass in a series of pulses at 1,500-year intervals.

20. An expanding halo of light is seen around a distant star, named V838 Monocerotis (V838 Mon). The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a flashbulb-like pulse of light in 2002.

21. This image shows a fine web of filamentary "bicycle-spoke" features embedded in the red and blue gas ring of the Helix Nebula, which is one of the nearest planetary nebulae to Earth.

22. A nearly perfect ring of hot, blue stars pinwheels about the yellow nucleus of an unusual galaxy known as Hoag's Object. The blue ring, which is dominated by clusters of young, massive stars, contrasts sharply with the yellow nucleus of mostly older stars. 

23. The Cone Nebula (NGC 2264) is giant pillar in a turbulent star-forming region 2,500 light-years away in the constellation Monoceros. Radiation from hot, young stars eroded the nebula over millions of years. Over time, only the densest regions of the Cone will be left. Inside these regions, stars and planets may form.

24. The Horsehead Nebula is part of a much larger complex in the constellation Orion. At about 1,500 light-years away, this complex is one of the nearest and most easily photographed regions in which massive stars are being formed.

25. The Hubble Ultra Deep Field is an image of a small area of space in the constellation Fornax. By collecting faint light over many hours of observation, it revealed thousands of galaxies, both nearby and very distant, making it the deepest image of the universe ever taken.

26. Messier 104 (M104) was named the Sombrero galaxy because of its resemblance to the broad rim and high-topped Mexican hat. As seen from Earth, the galaxy is tilted nearly edge-on. The galaxy is 50,000 light-years across and is located 28 million light-years from Earth.