ESO La Silla observes Lives and deaths of sibling stars

In this image from the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile young stars huddle together against a backdrop of clouds of glowing gas and lanes of dust. 

The star cluster, known as NGC 3293, would have been just a cloud of gas and dust itself about ten million years ago, but as stars began to form it became the bright group we see here. 

Clusters like this are celestial laboratories that allow astronomers to learn more about how stars evolve. 

Credit: ESO/G. Beccari

This beautiful star cluster, NGC 3293, is found 8000 light-years from Earth in the constellation of Carina (The Keel).

This cluster was first spotted by the French astronomer Nicolas-Louis de Lacaille in 1751, during his stay in what is now South Africa, using a tiny telescope with an aperture of just 12 millimetres.

It is one of the brightest clusters in the southern sky and can be easily seen with the naked eye on a dark clear night.

Star clusters like NGC 3293 contain stars that all formed at the same time, at the same distance from Earth and out of the same cloud of gas and dust, giving them the same chemical composition.

As a result clusters like this are ideal objects for testing stellar evolution theory.

Most of the stars seen here are very young, and the cluster itself is less than 10 million years old. Just babies on cosmic scales if you consider that the Sun is 4.6 billion years old and still only middle-aged.

An abundance of these bright, blue, youthful stars is common in open clusters like NGC 3293, and, for example, in the better known Kappa Crucis cluster, otherwise known as the Jewel Box (NGC 4755).

These open clusters each formed from a giant cloud of molecular gas and their stars are held together by their mutual gravitational attraction but these forces are not enough to hold a cluster together against close encounters with other clusters and clouds of gas as the cluster's own gas and dust dissipates.

So, open clusters will only last a few hundred million years, unlike their big cousins, the globular clusters, which can survive for billions of years, and hold on to far more stars.

Despite some evidence suggesting that there is still some ongoing star formation in NGC 3293, it is thought that most, if not all, of the nearly fifty stars in this cluster were born in one single event but even though these stars are all the same age, they do not all have the dazzling appearance of a star in its infancy; some of them look positively elderly, giving astronomers the chance to explore how and why stars evolve at different speeds.

Take the bright orange star at the bottom right of the cluster. This huge star, a red giant, would have been born as one of the biggest and most luminous of its litter, but bright stars burn out fast.

As the star used up the fuel at its core its internal dynamics changed and it began to swell and cool, becoming the red giant we now observe.

Red giants are reaching the end of their life cycle, but this red giant's sister stars are still in what is known as the pre-main-sequence, the period before the long, stable, middle period in a star's life.

We see these stars in the prime of their life as hot, bright and white against the red and dusty background.

ESO: Newborn Stars Will Rip Apart Their Stellar Nursery - Video

Massive young stars that will eventually destroy their own stellar nursery shine brightly in a dazzling new photo.

Cosmic gas cloud Gum 15, which lies 3,000 light-years from Earth, is busily giving birth to huge stars that are, in turn, shaping the cloud's weird structure.

That activity will eventually lead to the nebula's death, according to representatives of the European Southern Observatory (ESO).

The cloud consists of a collection of ionized hydrogen gas (HII), hydrogen atoms whose electrons were stripped by ultraviolet light.

It also includes one of the "culprit" stars in the future murder: HD 74804, a star visible at the center of the new image.

This chart shows the location of the star formation region Gum 15 (red circle) in the southern constellation of Vela (The Sails). 

Credit: ESO, IAU and Sky & Telescope

"Once the newly minted stars have passed through their infant stages, strong winds of particles will stream away from these large stars, sculpting and dispersing the gases around them," ESO officials wrote in a statement.

"When the most massive of these stars begin to die, Gum 15 will die with them," the researchers added.

"Some stars are so large that they will go out with a bang, exploding as supernovae and dispersing the region's last traces of HII, leaving behind just a cluster of infant stars."

Astronomers believe stars form in massive clouds of material such as this one, which are known as nebulas.

Hydrogen is the most abundant element in the cosmos, and is found in Earth's own sun (along with helium, which is produced as the sun fuses hydrogen in its core).

Gum 15 is an example of a so-called "HII region." It is one of many irregular shapes spotted by scientists around the cosmos.

The nebula's weird design comes from its irregular distribution of gas and dust, ESO stated.

This richly detailed new view from the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile shows the star formation region Gum 15. 

 Credit: ESO

Other famous examples of HII regions are found in the Eagle Nebula (home of the famous "Pillars of Creation" captured by the Hubble Space Telescope) and the Orion Nebula.

ESO captured the new image using the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile. Gum 15 is located in the southern constellation Vela (the Sails).

Gum gets its name from the late Australian astronomer Colin Gum, who created a catalogue of HII regions published in 1955.

ESO Messier 7: Diamonds in the tail of the scorpion - Video

This new image from the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile, shows the bright star cluster Messier 7, also known as NGC 6475. 

Easily spotted by the naked eye in the direction of the tail of the constellation of Scorpius (The Scorpion), this cluster is one of the most prominent open clusters of stars in the sky and an important research target. 

Credit: ESO

A new image from ESO's La Silla Observatory in Chile shows the bright star cluster Messier 7.

Easily spotted with the naked eye close to the tail of the constellation of Scorpius, it is one of the most prominent open clusters of stars in the sky—making it an important astronomical research target.

Messier 7, also known as NGC 6475, is a brilliant cluster of about 100 stars located some 800 light-years from Earth.

In this new picture from the Wide Field Imager on the MPG/ESO 2.2-metre telescope it stands out against a very rich background of hundreds of thousands of fainter stars, in the direction of the centre of the Milky Way.

At about 200 million years old, Messier 7 is a typical middle-aged open cluster, spanning a region of space about 25 light-years across.

As they age, the brightest stars in the picture, a population of up to a tenth of the total stars in the cluster, will violently explode as supernovae.

Looking further into the future, the remaining faint stars, which are much more numerous, will slowly drift apart until they become no longer recognisable as a cluster.


Open star clusters like Messier 7 are groups of stars born at almost the same time and place, from large cosmic clouds of gas and dust in their host galaxy.

These groups of stars are of great interest to scientists, because the stars in them have about the same age and chemical composition. This makes them invaluable for studying stellar structure and evolution.

An interesting feature in this image is that, although densely populated with stars, the background is not uniform and is noticeably streaked with dust.

This is most likely to be just a chance alignment of the cluster and the dust clouds.

Although it is tempting to speculate that these dark shreds are the remnants of the cloud from which the cluster formed, the Milky Way will have made nearly one full rotation during the life of this star cluster, with a lot of reorganisation of the stars and dust as a result.

So the dust and gas from which Messier 7 formed, and the star cluster itself, will have gone their separate ways long ago.

ESO Wide Field Imager Image: Young stars paint spectacular stellar landscape

The Wide Field Imager on the MPG/ESO 2.2-meter telescope at ESO's La Silla Observatory in Chile has captured the best image so far of the star cluster NGC 3572, a gathering of young stars, and its spectacular surroundings. 

This new image shows how the clouds of gas and dust around the cluster have been sculpted into whimsical bubbles, arcs and the odd features known as elephant trunks by the stellar winds flowing from the bright stars. 

The brightest of these cluster stars are heavier than the Sun and will end their short lives as supernova explosions. 

Credit: ESO/G. Beccari

Astronomers at ESO have captured the best image so far of the clouds around the star cluster NGC 3572.

This image shows how these clouds of gas and dust have been sculpted into bubbles, arcs and the odd features known as elephant trunks by the stellar winds flowing from this gathering of hot stars.

The brightest of these cluster stars are much heavier than the Sun and will end their short lives as supernova explosions.

Most stars do not form alone, but with many siblings that are created at about the same time from a single cloud of gas and dust. NGC 3572, in the southern constellation of Carina (The Keel), is one of these clusters.

It contains many hot young blue-white stars that shine brightly and generate powerful stellar winds that tend to gradually disperse the remaining gas and dust from their surroundings.

The glowing gas clouds and accompanying cluster of stars are the subjects of a new picture from the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile.

In the lower part of the image a big chunk of the molecular cloud that gave birth to these stellar youngsters still can be seen.

It has been dramatically affected by the powerful radiation coming from its smoldering offspring.

The radiation not only makes it glow with a characteristic hue, but also sculpts the clouds into amazingly convoluted shapes, including bubbles, arcs and the dark columns that astronomers call elephant trunks.

A strange feature captured in this image is the tiny ring-like nebula located slightly above the centre of the image.

Astronomers still are a little uncertain about the origin of this curious feature. It is probably a dense leftover from the molecular cloud that formed the cluster, perhaps a bubble created around a very bright hot star.

But some authors have considered that it may be some kind of oddly shaped planetary nebula—the remnants of a dying star.

ESA ESO Image: Large Sagittarius Star Cloud and a drop of Black

This image from the Wide Field Imager on the MPG/ESO 2.2-meter telescope at ESO's La Silla Observatory in Chile, shows the bright star cluster NGC 6520 and its neighbour, the strangely shaped dark cloud Barnard 86. 

This cosmic pair is set against millions of glowing stars from the brightest part of the Milky Way -- a region so dense with stars that barely any dark sky is seen across the picture. 

Credit: ESA, ESO.

This part of the constellation of Sagittarius (The Archer) is one of the richest star fields in the whole sky - the Large Sagittarius Star Cloud.

The huge number of stars that light up this region dramatically emphasise the blackness of dark clouds like Barnard 86, which appears at the centre of this new picture from the Wide Field Imager, an instrument mounted on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile.

This object, a small, isolated dark nebula known as a Bok globule, was described as "a drop of ink on the luminous sky" by its discoverer Edward Emerson Barnard, an American astronomer who discovered and photographed numerous comets, dark nebulae, one of Jupiter's moons, and made many other contributions.

An exceptional visual observer and keen astrophotographer, Barnard was the first to use long-exposure photography to explore dark nebulae.

Through a small telescope Barnard 86 looks like a dearth of stars, or a window onto a patch of distant, clearer sky.

However, this object is actually in the foreground of the star field - a cold, dark, dense cloud made up of small dust grains that block starlight and make the region appear opaque.

It is thought to have formed from the remnants of a molecular cloud that collapsed to form the nearby star cluster NGC 6520, seen just to the left of Barnard 86 in this image.

NGC 6520 is an open star cluster that contains many hot stars that glow bright blue-white, a telltale sign of their youth.

Open clusters usually contain a few thousand stars that all formed at the same time, giving them all the same age.

Such clusters usually only live comparatively short lives, on the order of several hundred million years, before drifting apart.

The incredible number of stars in this area of the sky muddles observations of this cluster, making it difficult to learn much about it.

NGC 6520's age is thought to be around 150 million years, and both this star cluster and its dusty neighbour are thought to lie at a distance of around 6000 light-years from our Sun.

The stars that appear to be within Barnard 86 in the image above are in fact in front of it, lying between us and the dark cloud.

Although it is not certain whether this is still happening within Barnard 86, many dark nebulae are known to have new stars forming in their centres - as seen in the famous Horsehead Nebula (eso0202), the striking object Lupus 3 (eso1303) and to a lesser extent in another of Barnard's discoveries, the Pipe Nebula (eso1233).

However, the light from the youngest stars is blocked by the surrounding dusty regions, and they can only be seen in infrared or longer-wavelength light.

ESA ESO Image of Pipe Nebula - Curious Dark Nebula

Just as Rene Magritte wrote "This is not a pipe" on his famous painting, this is also not a pipe. It is however a picture of part of a vast dark cloud of interstellar dust called the Pipe Nebula.

This new and very detailed image of what is also known as Barnard 59 was captured by the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory.

By coincidence this image is appearing on the 45th anniversary of the painter's death.

The Pipe Nebula is a prime example of a dark nebula. Originally, astronomers believed these were areas in space where there were no stars but it was later discovered that dark nebulae actually consist of clouds of interstellar dust so thick it can block out the light from the stars beyond.

The Pipe Nebula appears silhouetted against the rich star clouds close to the centre of the Milky Way in the constellation of Ophiuchus (The Serpent Bearer).

Barnard 59 forms the mouthpiece of the Pipe Nebula and is the subject of this new image from the Wide Field Imager on the MPG/ESO 2.2-metre telescope. This strange and complex dark nebula lies about 600-700 light-years away from Earth.

The nebula is named after the American astronomer Edward Emerson Barnard who was the first to systematically record dark nebulae using long-exposure photography and one of those who recognised their dusty nature.

Barnard catalogued a total of 370 dark nebulae all over the sky. A self-made man, he bought his first house with the prize money from discovering several comets.

Barnard was an extraordinary observer with exceptional eyesight who made contributions in many fields of astronomy in the late 19th and early 20th century.

At first glance, your attention is most likely drawn to the centre of the image where dark twisting clouds look a little like the legs of a vast spider stretched across a web of stars.

However, after a few moments you will begin to notice several finer details. Foggy, smoky shapes in the middle of the darkness are lit up by new stars that are forming.

Star formation is common within regions that contain dense, molecular clouds, such as in dark nebulae.

The dust and gas will clump together under the influence of gravity and more and more material will be attracted until the star is formed.

However, compared to similar regions, the Barnard 59 region is undergoing relatively little star formation and still has a great deal of dust.

If you look carefully you may also be able to spot more than a dozen tiny blue, green and red strips scattered across the picture.

These are asteroids, chunks of rock and metal a few kilometres across that are orbiting the Sun.

The majority lie in the asteroid belt between the orbits of Mars and Jupiter. Barnard 59 is about ten million times further away from the Earth than these tiny objects.

ESO Wide Field Imager Takes a deeper look at Centaurus A

The peculiar galaxy Centaurus A (NGC 5128) is pictured in this image taken with by the Wide Field Imager attached to the MPG/ESO 2.2-meter telescope at the La Silla Observatory in Chile. 

With a total exposure time of more than 50 hours this is probably the deepest view of this peculiar and spectacular object every created. Credit: ESO

Centaurus A, also known as NGC 5128, is a peculiar massive elliptical galaxy with a supermassive black hole at its heart.

It lies about 12 million light-years away in the southern constellation of Centaurus (The Centaur) and has the distinction of being the most prominent radio galaxy in the sky.

Astronomers think that the bright nucleus, strong radio emission and jet features of Centaurus A are produced by a central black hole with a mass of about 100 million times that of the Sun. Matter from the dense central parts of the galaxy releases vast amounts of energy as it falls towards the black hole.

This Wide Field Imager (WFI) picture allows us to appreciate the galaxy's elliptical nature, which shows up as the elongated shape of the fainter outer parts.

The glow that fills much of the picture comes from hundreds of billions of cooler and older stars. Unlike most elliptical galaxies, however, Centaurus A's smooth shape is disturbed by a broad and patchy band of dark material that obscures the galaxy's centre.

The dark band harbours large amounts of gas, dust and young stars. Bright young star clusters appear at the upper-right and lower-left edges of the band along with the red glow of star-forming clouds of hydrogen, whilst some isolated dust clouds are silhouetted against the stellar background.

These features, and the prominent radio emission, are strong evidence that Centaurus A is the result of a merger between two galaxies. The dusty band is probably the mangled remains of a spiral galaxy in the process of being ripped apart by the gravitational pull of the giant elliptical galaxy.

The new set of images from WFI include long exposures through red, green and blue filters as well as filters specially designed to isolate the light from glowing hydrogen and oxygen. The latter help us to spot the known optical jet features around Centaurus A, which were barely visible in a previous image from the Wide Field Imager.

Extending from the galaxy to the upper left corner of the image are two groups of reddish filaments, which are roughly lined up with the huge jets that are prominent in radio images. Both sets of filaments are stellar nurseries, containing hot young stars.

Above the left side of the dusty band, we find the inner filaments, lying about 30 000 light-years away of the nucleus. Further out, around 65 000 light-years away from the galaxy's nucleus and close to the upper left corner of the image, the outer filaments are visible. There is also possibly a very much fainter trace of a counter jet extending to the lower right.

Centaurus A has been extensively studied at wavelengths ranging from radio all the way to gamma-rays. In particular, radio and X-ray observations have been crucial for studying the interaction between the energetic output of the central supermassive black hole and its surroundings, see eso0903. Studies of Centaurus A with ALMA are just beginning.

Many of the observations of Centaurus A used to make this image were taken to see whether it was possible to use ground-based surveys to detect and study variable stars in galaxies like Centaurus A outside the local group. More than 200 new variable stars in Centaurus A were discovered.