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A stellar dust factory

STRIKING NEW OBSERVATIONS with the Atacama Large Millimetre/submillimetre Array (ALMA) telescope capture, for the first time, the remains of a recent supernova brimming with freshly formed dust. If enough of this dust makes the perilous transition into interstellar space, it could explain how many galaxies acquired their dusty, dusky appearance.

Cosmic dust consists of silicate and graphite grains – minerals also abundant on Earth. The soot from a candle is very similar to cosmic graphite dust, although the size of the grains in the soot are ten or more times bigger than typical grain sizes of cosmic graphite grains.

This image shows the remnant of Supernova 1987A

This image shows the remnant of Supernova 1987A seen in light of very different wavelengths. ALMA data (in red) shows newly formed dust in the middle of the remnant. Hubble Space Telescope (in green) and Chandra Space Observatory (in blue) data show the expanding shock wave. Credit: ALMA (ESO/NAOJ/NRAO) / A. Angelich. Visible light image: the NASA/ESA Hubble Space Telescope. X-Ray image: The NASA Chandra X-Ray Observatory

Galaxies can be remarkably dusty places and supernovae – exploded stars – are thought to be a primary source of that dust, especially in the early universe. But direct evidence of a supernova’s dust-making capabilities has been slim up to now, and could not account for the copious amount of dust detected in young, distant galaxies. But now observations with ALMA are changing that.

An international team of astronomers used ALMA to observe the glowing remains of Supernova 1987A, which is in the Large Magellanic Cloud, a dwarf galaxy orbiting the Milky Way about 160,000 light-years from Earth. SN 1987A is the closest observed supernova explosion since Johannes Kepler’s observation of a supernova inside the Milky Way in 1604. Being far in the southern sky, it is clearly visible only from the Southern Hemisphere.

The Tarantula Nebula and its surroundings

This is an image of the Tarantula Nebula and its surroundings in the Large Magellanic Cloud galaxy, taken in 1987. Supernova 1987A is the bright star just to the right of centre. Credit: ESO

“This is the first time we’ve been able to really image where the dust has formed, which is important in understanding the evolution of galaxies,” said Remy Indebetouw, an astronomer at the National Radio Astronomy Observatory (NRAO) and the University of Virginia, both in Charlottesville, USA

Astronomers predicted that as the gas cooled after the explosion, large amounts of dust would form as atoms of oxygen, carbon, and silicon bonded together in the cold central regions of the remnant. However, earlier observations of SN 1987A with infrared telescopes, made during the first 500 days after the explosion, detected only a small amount of hot dust.

With ALMA’s resolution and sensitivity, the team was able to image the far more abundant cold dust, which glows brightly in millimetre and submillimetre light. The astronomers estimate that the remnant cloud now contains about 25 percent the mass of the Sun in newly formed dust. They also found that significant amounts of carbon monoxide and silicon monoxide have formed.

Aerial view of dishes of the Atacama Large Millimetre/submillimetre Array

Aerial view of dishes of the Atacama Large Millimetre/submillimetre Array (ALMA) telescope. Credit: ALMA

“SN 1987A is a special place since it hasn’t mixed with the surrounding environment, so what we see there was made there,” said Indebetouw. “The new ALMA results, which are the first of their kind, reveal a supernova remnant chock full of material that simply did not exist a few decades ago.”

There’s more information on Supernova 1987A, including an interview with Australian astronomers, on the ABC’s web site.

Adapted from information issued by NRAO.

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Hubble spots a hidden treasure

Josh Lake's image of LHA 120-N11

Josh Lake’s image of LHA 120-N11, which comprises several adjacent pockets of gas and star formation. It is located in the Large Magellanic Cloud galaxy, roughly 200,000 light-years from Earth.

NEARLY 200,000 LIGHT-YEARS from Earth, the Large Magellanic Cloud, a satellite galaxy of the Milky Way, floats in space, in a long and slow dance around our galaxy.

Vast clouds of gas within it slowly collapse to form new stars. In turn, these light up the gas clouds in a riot of colours, visible in this image from the NASA/ESA Hubble Space Telescope.

The Large Magellanic Cloud (LMC) is ablaze with star-forming regions. From the Tarantula Nebula, the brightest stellar nursery in our cosmic neighbourhood, to LHA 120-N 11, part of which is featured in this Hubble image, the small and irregular galaxy is scattered with glowing nebulae, the most noticeable sign that new stars are being born.

The LMC is in an ideal position for astronomers to study the phenomena surrounding star formation. It lies in a fortuitous location in the sky, far enough from the plane of the Milky Way that it is neither outshone by too many nearby stars, nor obscured by the dust in the Milky Way’s centre.

It is also close enough to study in detail (less than a tenth of the distance of the Andromeda Galaxy, the closest spiral galaxy), and lies almost face-on to us, giving us a bird’s eye view.

Smokey remains of dead stars

LHA 120-N 11 (known as N11 for short) is a particularly bright region of the LMC, consisting of several adjacent pockets of gas and star formation. NGC 1769 (in the centre of this image) and NGC 1763 (to the right) are among the brightest parts.

In the centre of this image, a dark finger of dust blots out much of the light. While nebulae are mostly made of hydrogen, the simplest and most plentiful element in the universe, dust clouds are home to heavier and more complex elements, which go on to form rocky planets like the Earth.

Much finer than household dust (it is more like smoke), this interstellar dust consists of material expelled from previous generations of stars as they died.

The data in this image were identified by Josh Lake, an astronomy teacher at Pomfret School in Connecticut, USA, in the Hubble’s Hidden Treasures image processing competition. The competition invited members of the public to dig out unreleased scientific data from Hubble’s vast archive, and to process them into stunning images.

Josh Lake won first prize in the competition with an image (below) contrasting the light from glowing hydrogen and nitrogen in N 11. The image at the top of the page combines the data he identified with additional exposures taken in blue, green and near infrared light.

Josh Lake's image of NGC 1763

Josh Lake’s image of the NGC 1763 region of nebulosity and stars in the Large Magellanic Cloud galaxy. The image won him first prize in Hubble’s Hidden Treasures Image Processing Competition

More information: Hidden Treasures

Adapted from information issued by ESA / Hubble Information Centre. Images: NASA, ESA and J. Lake.

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Hubble’s birthday view of starbirth nebula

Hubble image of 30 Doradus

The amazing twirls and swirls of 30 Doradus, a starbirth region of gas and stars located in the Large Magellanic Cloud galaxy 170,000 light-years from Earth.

IT SEEMS HARD TO BELIEVE, but the Hubble Space Telescope has now been in orbit for 22 years. In that time it has advanced our understanding of the universe overall and of the stars, galaxies and nebulae within it.

To celebrate it’s birthday, Hubble scientists have released stunning new views of a “starbirth” region deep in the southern sky, known as 30 Doradus.

30 Doradus is part of the Tarantula Nebula, so-called for its resemblance to a spider, with tendrils of interstellar gas extending in many directions.

The Tarantula is located within the Large Magellanic Cloud galaxy, a close neighbour of the Milky Way about 170,000 light-years distant.

The main Hubble image is made up of many separate images “stitched” together. In fact, it is one of the largest Hubble images ever produced, and at the distance of the Tarantula covers a field 650 light-years across.

This starbirth region is home to numerous stars, young and old, big and small. Near the nebula’s heart is a star cluster called R136. It used to be thought that R136 contained the largest known star in the universe, R136a at 1,500 the mass of the Sun. It has since been determined, however, that R136a is itself a tight cluster of stars. Nevertheless, one of those stars, R136a1, is still the largest known at 265 times the mass of the Sun and 8,700,000 it’s brightness.

The radiance from all the stars has carved out intricate voids and valleys within the surrounding gas, and in some cases formed shockwaves or regions of increased gas density that could be triggering the inward collapse of gas clumps to form new stars.

See more and larger images of 30 Doradus at HubbleSite.

Close-up of part of 30 Doradus

This close-up of part of 30 Doradus shows a huge cavity in the gas, carved out by the stellar wind of young, powerful stars.

Hubble image of star cluster Hodge 301

This tight, bright cluster of stars within 30 Doradus is called Hodge 301. Unlike many of the youthful stars in 30 Doradus, many of those in Hodge 301 are ageing, red supergiants.

NGC 2070 with R136

At the heart of this portion of 30 Doradus lies the star cluster R136, which contains many of the heaviest known stars in the local universe.

Story by Jonathan Nally. Images credit: NASA, ESA, D. Lennon and E. Sabbi (ESA/STScI), J. Anderson, S. E. de Mink, R. van der Marel, T. Sohn, and N. Walborn (STScI), N. Bastian (Excellence Cluster, Munich), L. Bedin (INAF, Padua), E. Bressert (ESO), P. Crowther (University of Sheffield), A. de Koter (University of Amsterdam), C. Evans (UKATC/STFC, Edinburgh), A. Herrero (IAC, Tenerife), N. Langer (AifA, Bonn), I. Platais (JHU), and H. Sana (University of Amsterdam), and the Hubble Heritage Team (STScI/AURA)

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Australian dish charts where stars are born

The Large Magellanic Cloud

The Large Magellanic Cloud (LMC) is the nearest sizeable galaxy to our Milky Way, and is therefore a popular target for astronomers studying the evolution of stars.

ASTRONOMERS HAVE MAPPED in detail the star-forming regions of the nearest star-forming galaxy to our own, a step toward understanding the conditions surrounding star creation.

The researchers, led by University of Illinois astronomy professor Tony Wong—and including Associate Professor Sarah Maddison and PhD student Annie Hughes, both of the Swinburne University of Technology in Melbourne, Australia—have published their findings in the December issue of the Astrophysical Journal Supplement Series.

The Large Magellanic Cloud (LMC) is a popular galaxy among astronomers both for its nearness to our Milky Way and for the spectacular view it provides, a big-picture vista impossible to capture of our own galaxy.

“If you imagine a galaxy being a disc, the LMC is tilted almost face-on so we can look down on it, which gives us a very clear view of what’s going on inside,” Wong said.

Mopra dish

CSIRO's 22-metre-diameter Mopra radio telescope, located near Coonabarabran in NSW.

As the LMC is in the far southern sky, it is an ideal target for Australian telescopes. And indeed, the team used the CSIRO’s 22-metre-diameter radio telescope at Mopra, near Coonabarabran in north-central New South Wales.

Where are stars born?

Although astronomers have a working theory of how individual stars form, they know very little about what triggers the process or the conditions in space that are optimal for star birth.

Wong’s team focused on areas called molecular clouds, which are dense patches of gas—primarily molecular hydrogen—where stars are born. By studying these clouds and their relationship to new stars in the galaxy, the team hoped to learn more about how gas clouds turn into stars.

Using the Mopra dish, the astronomers mapped more than 100 molecular clouds in the LMC and estimated their sizes and masses, identifying regions with ample material for making stars. This seemingly simple task engendered a surprising find.

Conventional wisdom states that most of the molecular gas in a galaxy is apportioned to a few large clouds. However, Wong’s team found many more low-mass clouds than they expected—so many, in fact, that a majority of the dense gas may be sprinkled across the galaxy in these small molecular clouds, rather than clumped together in a few large blobs.

MAGMA image of the LMC

False-colour image of the Large Magellanic Cloud galaxy combining maps of neutral atomic hydrogen gas (red), hydrogen energised by nearby young stars (blue), and new data from Wong’s team which roughly show the locations of dense clouds of molecular hydrogen (green). It's thought that stars form within molecular hydrogen clouds.

Star formation widespread in the LMC galaxy

The large numbers of these relatively low-mass clouds means that star-forming conditions in the LMC may be relatively widespread and easy to achieve.

To better understand the connection between molecular clouds and star formation, the team compared their molecular cloud maps to maps of infrared radiation, which reveal where young stars are heating cosmic dust.

“It turns out that there’s actually very nice correspondence between these young massive stars and molecular clouds,” Wong said.

“We can say with great confidence that these clouds are where the stars form, but we are still trying to figure out why they have the properties they do,” he added.

Adapted from information issued by University of Illinois at Urbana-Champaign. Mopra photo courtesy CSIRO. MAGMA image of LMC courtesy Tony Wong, University of Illinois.

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Cosmic superbubble shaped by stars

N 44 superbubble nebula

The N 44 superbubble nebula is being formed by hot winds from bright, young stars.

THIS STRIKING VIEW shows a ‘superbubble’ nebula surrounding the young star cluster NGC 1929 within the Large Magellanic Cloud galaxy.

The superbubble (formally known as LHA 120-N 44) has been produced by the combination of two processes. Firstly, stellar winds—streams of charged particles from the very hot and massive stars in the central cluster—cleared out the central region. Then massive stars exploded as supernovae, producing shockwaves and pushing the gas out further to form the glowing bubble.

The vast shell of material is around 325 by 250 light-years across. For comparison, the nearest star to our Sun is just over four light-years away.

The Large Magellanic Cloud is a small neighbouring galaxy to the Milky Way. It contains many regions where clouds of gas and dust are forming new stars.

Although the superbubble is shaped by destructive forces, new stars are forming around the edges where the gas is being compressed. Like recycling on a cosmic scale, this next generation of stars will breathe fresh life into NGC 1929.

The image was made by the European Southern Observatory (ESO) from observational data collected by the Very Large Telescope and identified by Manu Mejias, from Argentina, who participated in ESO’s Hidden Treasures 2010 astrophotography competition.

Download desktop wallpapers:

NGC 1929 superbubble 1024×768 (413.1 KB)

NGC 1929 superbubble 1280×1024 (657.3 KB)

NGC 1929 superbubble 1600×1200 (952.2 KB)

NGC 1929 superbubble 1920×1200 (986.2 KB)

Adapted from information issued by ESO / Manu Mejias.

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Blast from the past glows anew

Hubble image of SN 1987A

This Hubble Space Telescope image of SN 1987A shows an odd-shaped central blob of debris from the exploded star, which has now begun to brighten. The brightening is due to illumination by X-rays coming from the surrounding ring of hot gas.

IN 1987, LIGHT FROM AN EXPLODING STAR in a neighbouring galaxy, the Large Magellanic Cloud, reached Earth. Named Supernova 1987A, it was the closest supernova explosion witnessed in almost 400 years, and its proximity has enabled astronomers to study it in unprecedented detail as it evolves.

A team of astronomers has now announced that the supernova debris, which had been fading over the years, is now brightening. This shows that a different “power source” has begun to light up the debris, and marks its transition from a supernova to a supernova remnant.

“Supernova 1987A has become the youngest supernova remnant visible to us,” said Robert Kirshner of the Harvard-Smithsonian Centre for Astrophysics (CfA).

Kirshner leads a long-term study of SN 1987A with NASA’s Hubble Space Telescope. Since its launch in 1990, Hubble has provided a continuous record of the changes in SN 1987A.

A new power source

SN 1987A is surrounded by a ring of gas that blew off the progenitor star thousands of years before it exploded. The ring is about one light-year (10 trillion kilometres) across. Inside that ring, the “guts” of the star are rushing outward in an expanding debris cloud.

Most of a supernova’s light comes from radioactive decay of elements created in the explosion. As a result, it fades over time. However, the debris from SN 1987A has begun to brighten, suggesting that a new power source is lighting it.

Supernova 1987A

Supernova 1987A was the closest exploding star seen in almost 400 years. Astronomers are continuing with long-term studies of it.

“It’s only possible to see this brightening because SN 1987A is so close and Hubble has such sharp vision,” Kirshner said.

A supernova remnant consists of material ejected from an exploding star, as well as the pre-existing material the blast wave sweeps up.

The outflowing debris from SN 1987A is beginning to crash into the surrounding gas ring, creating powerful shock waves that generate X-rays, which have been detected by NASA’s Chandra X-ray Observatory. Those X-rays are illuminating the debris, and shock heating is making it glow.

The same process powers other well-known supernova remnants in our galaxy, such as Cassiopeia A.

Change you can see

Because it’s so young, the remnant of SN 1987A still shows the history of the last few thousand years of the star’s life recorded in the knots and whorls of gas. By studying it further, astronomers may decode that history.

“Young supernova remnants have personality,” Kirshner agreed.

Eventually, that history will be lost when the bulk of the expanding stellar debris hits the surrounding ring and shreds it. Until then, SN 1987A continues to offer an unprecedented opportunity to watch a cosmic object change over the course of a human lifetime. Few other objects in the sky evolve on such short time-scales.

Adapted from information issued by the Harvard-Smithsonian Centre for Astrophysics. Images courtesy NASA / P. Challis (CfA) / David Malin (AAO).

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Diamond stars in a sea of colour

R136

R136 is a group of young, hot, massive stars in the 30 Doradus Nebula in the Large Magellanic Cloud, a galaxy close to our Milky Way.

THIS MASSIVE, YOUNG STELLAR grouping, called R136, is only a few million years old and resides in the 30 Doradus Nebula, a turbulent star-birth region in the Large Magellanic Cloud (LMC), a satellite galaxy of our Milky Way.

Many of the diamond-like icy blue stars are among the most massive stars known. Several of them are over 100 times more massive than our Sun. These hefty stars are destined to pop off, like a string of firecrackers, as supernovae in a few million years.

The image, made from exposures in ultraviolet, visible, and red light by Hubble’s Wide Field Camera 3, spans about 100 light-years.

Despite being in another galaxy, the nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars’ birth and evolution. There is no known star-forming region in our galaxy as large or as prolific as 30 Doradus.

The brilliant stars are carving deep cavities in the surrounding material by unleashing a torrent of ultraviolet light, and hurricane-force stellar winds (streams of charged particles), which are etching away the enveloping hydrogen gas cloud in which the stars were born.

The image reveals a fantasy landscape of pillars, ridges, and valleys, as well as a dark region in the centre. The brilliant stars can also help create a successive generation of offspring—when the winds hit dense walls of gas, they create shockwaves, which compress the gas and potentially triggers a new wave of star birth.

The cluster is a rare example of the many super star clusters that formed in the distant, early universe, when star birth and galaxy interactions were more frequent. Previous Hubble observations have shown astronomers that super star clusters in faraway galaxies are common.

The LMC is located 170,000 light-years away and is a member of the Local Group of Galaxies, which also includes the Milky Way.

The Hubble observations were taken October 20-27, 2009. The blue colour is light from the hottest, most massive stars; the green from the glow of oxygen; and the red from fluorescing hydrogen.

Full-size image suitable for screen wallpaper (1280 x 1280 pixels)

Adapted from information issued by NASA, ESA, and F. Paresce (INAF-IASF, Bologna, Italy), R. O’Connell (University of Virginia, Charlottesville), and the Wide Field Camera 3 Science Oversight Committee.

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Hubble’s cosmic bauble

Hubble image of SNR B0509-67.5

This delicate shell formed as the expanding blast wave and ejected material from a supernova (an exploding star) tore through the surrounding interstellar gas. It is located in the Large Magellanic Cloud (LMC), a small galaxy about 160 000 light-years from Earth.

  • Expanding shell of gas from an exploded star
  • Explosion occurred about 400 years ago
  • Image made from combined Hubble images

Hubble has spotted a festive bauble of gas in our neighbouring galaxy, the Large Magellanic Cloud. Formed in the aftermath of a supernova explosion that took place four centuries ago, this sphere of gas has been snapped in a series of observations made between 2006 and 2010.

The delicate shell, photographed by the NASA/ESA Hubble Space Telescope, appears to float serenely in the depths of space, but this apparent calm hides an inner turmoil. The gaseous envelope formed as the expanding blast wave and ejected material from a supernova tore through the nearby interstellar medium.

Called SNR B0509-67.5 (or SNR 0509 for short), the bubble is the visible remnant of a powerful stellar explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light-years from Earth.

Ripples seen in the shell’s surface may be caused either by subtle variations in the density of the ambient interstellar gas, or possibly be driven from the interior by fragments from the initial explosion.

The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 18 million km/h.

Hubble and Chandra image of SNR B0509-67.5

The Hubble images overlaid with data (green) from NASA’s Chandra X-ray Observatory that show where the gas is so hot that it emits high-powered X-rays. The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 18 million km/h.

Astronomers have concluded that the explosion was an example of an especially energetic and bright variety of supernova. Known as Type Ia, such supernova events are thought to result when a white dwarf star in a binary system robs its partner of gas, taking on more mass than it is able to handle, so that it eventually explodes.

Hubble’s Advanced Camera for Surveys observed the supernova remnant on 28 October 2006 with a filter that isolates light from the glowing hydrogen seen in the expanding shell. These observations were then combined with visible-light images of the surrounding star field that were imaged with Hubble’s Wide Field Camera 3 on 4 November 2010.

With an age of about 400 years, the supernova might have been visible to Southern Hemisphere observers around the year 1600, although there are no known records of a “new star” in the direction of the LMC near that time.

A much more recent supernova in the LMC, SN 1987A, did catch the eye of Earth viewers and continues to be studied with ground- and space-based telescopes, including Hubble.

Adapted from information issued by the ESA–Hubble Information Centre. Image credit: NASA / ESA / Hubble Heritage Team (STScI/AURA) / CXC / SAO. Acknowledgement: J. Hughes (Rutgers University).

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Pulsating star mystery solved

Artist's impression of OGLE-LMC-CEP0227

Artist's impression of the binary star OGLE-LMC-CEP0227. The smaller of the two stars is a pulsating Cepheid variable and the orientation of the system is such that the stars eclipse each other during their orbits.

A lucky alignment of orbits has enabled astronomers measure the mass of a specific kind of star, and in the process solve a decades-old mystery.

The star in question is of a type known as a ‘Cepheid variable’, or just Cepheid. Cepheids are unstable stars that are larger and much brighter than the Sun. They expand and contract in a regular way, taking anything from a few days to months to complete the cycle.

The time taken to brighten and fade again is longer for stars that are more luminous and shorter for the dimmer ones. This is known as the period-luminosity relation.

Astronomers can use this to their advantage when estimating the distances to galaxies. By timing the rise and fall in light of a Cepheid in a distant galaxy, they can work out how intrinsically bright the star must be.

By comparing that inherent brightness with the actual brightness measured, they can work out how far away the star must be.

The Cepheid period-luminosity relation, discovered by Henrietta Leavitt in 1908, was used by Edwin Hubble to make the first estimates of the distance to what we now know to be galaxies.

More recently Cepheids have been studied with the Hubble Space Telescope and with ground-based telescopes to make highly accurate distance estimates to many nearby galaxies.

The period-luminosity relation makes the study of Cepheids one of the most effective ways to measure the distances to nearby galaxies and from there to map out the scale of the whole Universe.

Large Magellanic Cloud

The Large Magellanic Cloud galaxy, in which the Cepheid star was discovered. Further Cepheid discoveries in this galaxy could help astronomers pin down its distance to better than 1% precision.

Competing theories

Unfortunately, despite their importance, Cepheids are not fully understood. In particular, predictions of their masses derived from the theory of pulsating stars are 20% less than predictions from the theory of the evolution of stars. This embarrassing discrepancy has been known since the 1960s.

To resolve this mystery, astronomers needed to find a binary star containing a Cepheid where the orbit happened to be seen edge-on from Earth. In these cases, known as eclipsing binaries, the brightness of the two stars dims as one passes in front of the other, and again when it passes behind the other star.

In pairs such as these, astronomers can determine the masses of the stars to high accuracy using well-known physical laws.

Unfortunately, neither Cepheids nor eclipsing binaries are common, so the chance of finding such an unusual pair seemed very low. None are known in the Milky Way.

“Very recently we actually found the double star system we had hoped for among the stars of the Large Magellanic Cloud,” says Wolfgang Gieren, a member of the team. The Large Magellanic Cloud is a small galaxy that orbits our Milky Way galaxy at a distance of around 160,000 light-years.

The system “contains a Cepheid variable star pulsating every 3.8 days,” adds Gieren. “The other star is slightly bigger and cooler, and the two stars orbit each other in 310 days.”

The observers carefully measured the brightness variations of this rare object, known as OGLE-LMC-CEP0227, as the two stars orbited and passed in front of one another. They also used spectrographs to measure the motions of the stars towards and away from the Earth—both the orbital motion of both stars and the in-and-out motion of the surface of the Cepheid as it swelled and contracted.

This very complete and detailed data allowed the observers to determine the orbital motion, sizes and masses of the two stars with very high accuracy—far surpassing what had been done before for a Cepheid.

The mass of the Cepheid is now known to about 1% and agrees exactly with predictions from the theory of stellar pulsation. The larger mass predicted by stellar evolution theory was shown to be significantly in error.

The team hopes to find other examples of these remarkably useful pairs of stars to exploit the method further. They think that from such binary systems they will eventually be able to pin down the distance to the Large Magellanic Cloud to 1%, which would mean an extremely important improvement of the cosmic distance scale.

Adapted from information issued by ESO / L. Calçada.

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Incredible Hubble video

This Hubblecast features a spectacular new NASA/ESA Hubble Space Telescope image—one of the largest ever released of a star-forming region. It highlights N11, part of a complex network of gas clouds and star clusters within our neighbouring galaxy, the Large Magellanic Cloud. This region of energetic star formation is one of the most active in the nearby Universe.

Download an amazing screen wallpaper image of N11:

Adapted from information issued by NASA / ESA / Jesús Maíz Apellániz (Instituto de Astrofísica de Andalucía, Spain).

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