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This image of the Egg Nebula, also known as CRL2688 and located roughly 3, 000 light-years from us, was taken in red light with the Wide Field and Planetary Camera 2 (WFPC2) aboard the Hubble Space Telescope.

This image sheds new light on the poorly understood ejection of stellar matter which accompanies the slow death of Sun-like stars.

Using new observations from ESO�s VLT Survey Telescope, astronomers have discovered three different populations of young stars within the Orion Nebula Cluster. This unexpected discovery adds very valuable new insights for the understanding of how such clusters form. It suggests that star formation might proceed in bursts, where each burst occurs on a much faster time-scale than previously thought.

OmegaCAM � the wide-field optical camera on ESO�s VLT Survey Telescope (VST) � has captured the spectacular Orion Nebula and its associated cluster of young stars in great detail, producing a beautiful new image. This object is one of the closest stellar nurseries for both low and high-mass stars, at a distance of about 1350 light-years.

But this is more than just a pretty picture. A team led by ESO astronomer Giacomo Beccari has used these data of unparallelled quality to precisely measure the brightness and colours of all the stars in the Orion Nebula Cluster. These measurements allowed the astronomers to determine the mass and ages of the stars. To their surprise, the data revealed three different sequences of potentially different ages.

�Looking at the data for the first time was one of those �Wow!� moments that happen only once or twice in an astronomers lifetime,� says Beccari, lead �author of the paper presenting the results. �The incredible quality of the OmegaCAM images revealed without any doubt that we were seeing three distinct populations of stars in the central parts of Orion.�

Monika Petr-Gotzens, co-author and also based at ESO Garching, continues, �This is an important result. What we are witnessing is that the stars of a cluster at the beginning of their lives didn�t form altogether simultaneously. This may mean that our understanding of how stars form in clusters needs to be modified.�

The astronomers looked carefully at the possibility that instead of indicating different ages, the different brightnesses and colours of some of the stars were due to hidden companion stars, which would make the stars appear brighter and redder than they really were. But this idea would imply quite unusual properties of the pairs, which have never before been observed. Other measurements of the stars, such as their rotation speeds and spectra, also indicated that they must have different ages.

�Although we cannot yet formally disprove the possibility that these stars are binaries, it seems much more natural to accept that what we see are three generations of stars that formed in succession, within less than three million years,� concludes Beccari.

The new results strongly suggest that star formation in the Orion Nebula Cluster is proceeding in bursts, and more quickly than had been previously thought.

The NASA/ESA Hubble Space Telescope has taken a striking high resolution image of the curious planetary nebula NGC 6210. Located about 6500 light-years away, in the constellation of Hercules, NGC 6210 was discovered in 1825 by the German astronomer Friedrich Georg Wilhelm Struve. Although in a small telescope it appears only as a tiny disc, it is fairly bright.

NGC 6210 is the last gasp of a star slightly less massive than our Sun at the final stage of its life cycle. The multiple shells of material ejected by the dying star form a superposition of structures with different degrees of symmetry, giving NGC 6210 its odd shape. This sharp image shows the inner region of this planetary nebula in unprecedented detail, where the central star is surrounded by a thin, bluish bubble that reveals a delicate filamentary structure. This bubble is superposed onto an asymmetric, reddish gas formation where holes, filaments and pillars are clearly visible.

The life of a star ends when the fuel available to its thermonuclear engine runs out. The estimated lifetime for a Sun-like star is some ten billion years. When the star is about to expire, it becomes unstable and ejects its outer layers, forming a planetary nebula and leaving behind a tiny, but very hot, remnant, known as white dwarf. This compact object, here visible at the centre of the image, cools down and fades very slowly. Stellar evolution theory predicts that our Sun will experience the same fate as NGC 6210 in about five billion years.

This picture was created from images taken with Hubble�s Wide Field Planetary Camera 2 through three filters: the broadband filter F555W (yellow) and the narrowband filters F656N (ionised hydrogen), F658N (ionised nitrogen) and F502N (ionised oxygen). The exposure times were 80 s, 140 s, 800 s and 700 s respectively and the field of view is only about 28 arcseconds across.

In the year 1054 A.D., Chinese astronomers were startled by the appearance of a new star that was so bright that it was visible in broad daylight for several weeks. Located about 6,500 light-years from Earth, the Crab Nebula is the remnant of a star that began its life with about 10 times the mass of our sun. Its life ended on July 4, 1054 when it exploded as a supernova.

Resembling an abstract painting by Jackson Pollock, the image shows ragged shards of gas that are expanding away from the explosion site at over 3 million miles per hour. The core of the star has survived the explosion as a pulsar, a neutron star that spins on its axis 30 times a second. It heats its surroundings, creating the ghostly diffuse bluish-green glowing gas cloud in its vicinity. The colorful network of filaments is the material from the outer layers of the star that was expelled during the explosion. The various colors in the picture arise from different chemical elements in the expanding gas, including hydrogen (orange), nitrogen (red), sulfur (pink), and oxygen (green). The shades of color represent variations in the temperature and density of the gas, as well as changes in the elemental composition.

This picture shows the Boomerang Nebula, a protoplanetary nebula, as seen by the Atacama Large Millimeter/submillimeter Array (ALMA). The background purple structure, as seen in visible light with the NASA/ESA Hubble Space Telescope, shows a classic double-lobe shape with a very narrow central region. ALMA�s ability to see the cold molecular gas reveals the nebula�s more elongated shape, in orange.

Since 2003 the nebula, located about 5000 light-years from Earth, has held the record for the coldest known object in the Universe. The nebula is thought to have formed from the envelope of a star in its later stages of life which engulfed a smaller, binary companion. It is possible that this is the cause of the ultra-cold outflows, which are illuminated by the light of the central, dying star.

ALMA looked at the nebula�s central dusty disc and the outflows further out, which span a distance of almost four light-years across the sky. These outflows are even colder than the cosmic microwave background, reaching temperatures below �270 �C. The outflows are also expanding at a speed of 590 000 kilometres per hour.

The coupling of the AOF with MUSE gives access to both greater sharpness and a wide dynamic range when observing celestial objects like planetary nebulae. These new observations of IC 4406 revealed shells that have never been seen before, along with the already familiar dark dust structures in the nebula that gave it the popular name the Retina Nebula.

This image shows a small fraction of the total data collected by the MUSE using the AOF system and demonstrates the increased abilities of the new AOF equipped MUSE instrument.

This image shows smaller, particularly interesting areas of the Orion Nebula. It shows the delicate tracery created at the so-called Bright Bar, as the intense UV-light and strong winds from the hot Trapezium stars eat their way into the surrounding molecular cloud. Also visible are a number of very young red objects partly hidden in the cloud, waiting to be revealed as new members of the Trapezium Cluster.

The Veil Nebula is a cloud of heated and ionized gas and dust in the constellation Cygnus. It constitutes the visible portions of the Cygnus Loop (radio source W78, or Sharpless 103), a large but relatively faint supernova remnant. The source supernova exploded circa 3,000 BC to 6,000 BC, and the remnants have since expanded to cover an area roughly 3 degrees in diameter (about 6 times the diameter, or 36 times the area, of the full moon). The distance to the nebula is not precisely known, but Far Ultraviolet Spectroscopic Explorer (FUSE) data supports a distance of about 1,470 light-years.

Amboseli National Park, Kajiado County, Kenya

Two of the sky�s more famous residents share the stage with a lesser-known neighbour in this enormous new three gigapixel image from ESO�s VLT Survey Telescope (VST). On the right lies the faint, glowing cloud of gas called Sharpless 2-54, the iconic Eagle Nebula is in the centre, and the Omega Nebula to the left. This cosmic trio makes up just a portion of a vast complex of gas and dust within which new stars are springing to life and illuminating their surroundings.

Sharpless 2-54 and the Eagle and Omega Nebulae are located roughly 7000 light-years away � the first two fall within the constellation of Serpens (The Serpent), while the latter lies within Sagittarius (The Archer). This region of the Milky Way houses a huge cloud of star-making material. The three nebulae indicate where regions of this cloud have clumped together and collapsed to form new stars; the energetic light from these stellar newborns has caused ambient gas to emit light of its own, which takes on the pinkish hue characteristic of areas rich in hydrogen.

Two of the objects in this image were discovered in a similar way. Astronomers first spotted bright star clusters in both Sharpless 2-54 and the Eagle Nebula, later identifying the vast, comparatively faint gas clouds swaddling the clusters. In the case of Sharpless 2-54, British astronomer William Herschel initially noticed its beaming star cluster in 1784. That cluster, catalogued as NGC 6604, appears in this image on the object�s left side. The associated very dim gas cloud remained unknown until the 1950s, when American astronomer Stewart Sharpless spotted it on photographs from the National Geographic Society�Palomar Observatory Sky Survey.

The Eagle Nebula did not have to wait so long for its full glory to be appreciated. Swiss astronomer Philippe Loys de Ch�seaux first discovered its bright star cluster, NGC 6611, in 1745 or 1746. A couple of decades later, French astronomer Charles Messier observed this patch of sky and also documented the nebulosity present there, recording the object as Messier 16 in his influential catalogue.

As for the Omega Nebula, de Ch�seaux did manage to observe its more prominent glow and duly noted it as a nebula in 1745. However, because the Swiss astronomer�s catalogue never achieved wider renown, Messier�s re-discovery of the Omega Nebula in 1764 led to its becoming Messier 17, the seventeenth object in the Frenchman�s popular compendium.

The observations from which this image was created were taken with ESO�s VLT Survey Telescope (VST), located at ESO�s Paranal Observatory in Chile. The huge final colour image was created by mosaicing dozens of pictures � each of 256 megapixels � from the telescope�s large-format OmegaCAM camera. The final result, which needed lengthy processing, totals 3.3 gigapixels, one of the largest images ever released by ESO.

The planetary nebula NGC 6563 resides in a crowded starry region of the sky. In natural sky conditions many of these stars remain invisible due to the blurring effect of the Earth�s atmosphere. When the AOF supplies its superb correction a myriad fainter stars become visible, together with a sharper view of the dusty parts of the nebula itself.

The central region of the Orion Nebula (M42, NGC 1976) as seen in the near-infrared by the High Acuity Wide field K-band Imager (HAWK-I) instrument at ESOs Very Large Telescope at Paranal.

Known as the Little Ghost Nebula, NGC 6369 is a planetary nebula in the constellation Ophiuchus, the serpent-bearer. The nebula is relatively faint with an apparent magnitude of 12.9 and the clear detail of this image shows the power of the AOF-equipped MUSE instrument of the VLT. The white dwarf star is clearly visible in the middle of the nebular gas, which is expanding out in rings.

Named for its resemblance to a coiling spiral seen face on, the Helix Nebula (NGC 7293) is a challenging stargazing target that has a more complex three-dimensional structure than expected. Now, the nebula has a new portrait, created by the penetrating infrared gaze of NASAs Spitzer Space Telescope, which was released at the 207th meeting of the American Astronomical Society on Jan. 9, 2006.

The nebula, which is composed of gaseous shells and disks puffed out by a dying sunlike star, exhibits complex structure on even the smallest visible scales.

This image is a composite of infrared data from Spitzer and visible-light data from NASAs Hubble Space Telescope.