Saturday, June 25, 2016

NASA's K2 Finds Newborn Exoplanet Around Young Star

When a planet such as K2-33b passes in front of its host star, it blocks some of the star's light. Observing this periodic dimming, called a transit, from continual monitoring of a star's brightness, allows astronomers to detect planets outside our solar system with a high degree of certainty. This Neptune-sized planet orbits a star that is between 5 and 10 million years old. In addition to the planet, the star hosts a disk of planetary debris, seen as a bright ring encircling the star. Youtube

K2-33b, shown in this illustration, is one of the youngest exoplanets detected to date. It makes a complete orbit around its star in about five days. 
Credits: NASA/JPL-Caltech.

This image shows the K2-33 system, and its planet K2-33b, compared to our own solar system. The planet has a five-day orbit, whereas Mercury orbits our sun in 88 days. The planet is also nearly 10 times closer to its star than Mercury is to the sun. Credits: NASA/JPL-Caltech


Astronomers have discovered the youngest fully formed exoplanet ever detected. The discovery was made using NASA's Kepler Space Telescope and its extended K2 mission, as well as the W. M. Keck Observatory on Mauna Kea, Hawaii. Exoplanets are planets that orbit stars beyond our sun.

The newfound planet, K2-33b, is a bit larger than Neptune and whips tightly around its star every five days. It is only 5 to 10 million years old, making it one of a very few newborn planets found to date.

"Our Earth is roughly 4.5 billion years old," said Trevor David of Caltech in Pasadena, lead author of a new study published online June 20, 2016, in the journal Nature. "By comparison, the planet K2-33b is very young. You might think of it as an infant." David is a graduate student working with astronomer Lynne Hillenbrand, also of Caltech.

Planet formation is a complex and tumultuous process that remains shrouded in mystery. Astronomers have discovered and confirmed roughly 3,000 exoplanets so far; however, nearly all of them are hosted by middle-aged stars, with ages of a billion years or more. For astronomers, attempting to understand the life cycles of planetary systems using existing examples is like trying to learn how people grow from babies to children to teenagers, by only studying adults.

"The newborn planet will help us better understand how planets form, which is important for understanding the processes that led to the formation of Earth," said co-author Erik Petigura of Caltech.

The first signals of the planet's existence were measured by K2. The telescope's camera detected a periodic dimming of the light emitted by the planet's host star, a sign that an orbiting planet could be regularly passing in front of the star and blocking the light. Data from the Keck Observatory validated that the dimming was indeed caused by a planet, and also helped confirm its youthful age.

Infrared measurements from NASA's Spitzer Space Telescope showed that the system's star is surrounded by a thin disk of planetary debris, indicating that its planet-formation phase is wrapping up. Planets form out of thick disks of gas and dust, called protoplanetary disks, that surround young stars.

"Initially, this material may obscure any forming planets, but after a few million years, the dust starts to dissipate," said co-author Anne Marie Cody, a NASA Postdoctoral Program fellow at NASA's Ames Research Center in California's Silicon Valley. "It is during this time window that we can begin to detect the signatures of youthful planets with K2." 

A surprising feature in the discovery of K2-33b is how close the newborn planet lies to its star. The planet is nearly 10 times closer to its star than Mercury is to our sun, making it hot. While numerous older exoplanets have been found orbiting very tightly to their stars, astronomers have long struggled to understand how more massive planets like this one wind up in such small orbits. Some theories propose that it takes hundreds of millions of years to bring a planet from a more distant orbit into a close one -- and therefore cannot explain K2-33b, which is quite a bit younger.

The science team says there are two main theories that may explain how K2-33b wound up so close to its star. It could have migrated there in a process called disk migration that takes hundreds of thousands of years. Or, the planet could have formed "in situ" -- right where it is. The discovery of K2-33b therefore gives theorists a new data point to ponder.

"After the first discoveries of massive exoplanets on close orbits about 20 years ago, it was immediately suggested that they could absolutely not have formed there, but in the past several years, some momentum has grown for in situ formation theories, so the idea is not as wild as it once seemed," said David.

"The question we are answering is: Did those planets take a long time to get into those hot orbits, or could they have been there from a very early stage? We are saying, at least in this one case, that they can indeed be there at a very early stage," he said.

Ames manages the Kepler and K2 missions for NASA's Science Mission Directorate. NASA's Jet Propulsion Laboratory in Pasadena, California, managed Kepler mission development. Ball Aerospace & Technologies Corporation operates the flight system with support from the Laboratory for Atmospheric and Space Physics at the University of Colorado at Boulder.


Elizabeth Landau
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6425

elizabeth.landau@jpl.nasa.gov

Michele Johnson
Ames Research Center, Moffett Field, Calif.
650-604-6982

michele.johnson@nasa.gov

Felicia Chou
NASA Headquarters, Washington
202-358-0257

felicia.chou@nasa.gov

Written by Whitney Clavin
Editor: Tony Greicius


Friday, June 24, 2016

Hubble Confirms New Dark Spot on Neptune

Dark Spot on Neptune
Credit: NASA, ESA, and M.H. Wong and J. Tollefson (UC Berkeley)

Scale and Compass Image for Dark Spot on Neptune
Credit: NASA, ESA, and Z. Levay (STScI)
Acknowledgment: M.H. Wong and J. Tollefson (UC Berkeley)


New images obtained on May 16, 2016, by NASA's Hubble Space Telescope confirm the presence of a dark vortex in the atmosphere of Neptune. Though similar features were seen during the Voyager 2 flyby of Neptune in 1989 and by the Hubble Space Telescope in 1994, this vortex is the first one observed on Neptune in the 21st century.

The discovery was announced on May 17, 2016, in a Central Bureau for Astronomical Telegrams (CBAT) electronic telegram by University of California at Berkeley research astronomer Mike Wong, who led the team that analyzed the Hubble data.

Neptune's dark vortices are high-pressure systems and are usually accompanied by bright "companion clouds," which are also now visible on the distant planet. The bright clouds form when the flow of ambient air is perturbed and diverted upward over the dark vortex, causing gases to likely freeze into methane ice crystals. "Dark vortices coast through the atmosphere like huge, lens-shaped gaseous mountains," Wong said. "And the companion clouds are similar to so-called orographic clouds that appear as pancake-shaped features lingering over mountains on Earth."

Beginning in July 2015, bright clouds were again seen on Neptune by several observers, from amateurs to astronomers at the W. M. Keck Observatory in Hawaii. Astronomers suspected that these clouds might be bright companion clouds following an unseen dark vortex. Neptune's dark vortices are typically only seen at blue wavelengths, and only Hubble has the high resolution required for seeing them on distant Neptune.

In September 2015, the Outer Planet Atmospheres Legacy (OPAL) program, a long-term Hubble Space Telescope project that annually captures global maps of the outer planets, revealed a dark spot close to the location of the bright clouds, which had been tracked from the ground. By viewing the vortex a second time, the new Hubble images confirm that OPAL really detected a long-lived feature. The new data enabled the team to create a higher-quality map of the vortex and its surroundings.

Neptune's dark vortices have exhibited surprising diversity over the years, in terms of size, shape, and stability (they meander in latitude, and sometimes speed up or slow down). They also come and go on much shorter timescales compared to similar anticyclones seen on Jupiter; large storms on Jupiter evolve over decades.

Planetary astronomers hope to better understand how dark vortices originate, what controls their drifts and oscillations, how they interact with the environment, and how they eventually dissipate, according to UC Berkeley doctoral student Joshua Tollefson, who was recently awarded a prestigious NASA Earth and Space Science Fellowship to study Neptune's atmosphere. Measuring the evolution of the new dark vortex will extend knowledge of both the dark vortices themselves, as well as the structure and dynamics of the surrounding atmosphere.

The team, led by Wong, also included the OPAL team (Wong, Amy Simon, and Glenn Orton), UC Berkeley collaborators (Imke de Pater, Joshua Tollefson, and Katherine de Kleer), Heidi Hammel (AURA), Statia Luszcz-Cook (AMNH), Ricardo Hueso and Agustin Sánchez-Lavega (Universidad del Pais Vasco), Marc Delcroix (Société Astronomique de France), Larry Sromovsky and Patrick Fry (University of Wisconsin), and Christoph Baranec (University of Hawaii).


Contacts

Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4493 / 410-338-4514

dweaver@stsci.edu / villard@stsci.edu

Robert Sanders
University of California, Berkeley, California
510-643-6998

rlsanders@berkeley.edu

Mike Wong
University of California, Berkeley, California

mikewong@astro.berkeley.edu


Source: HubbleSite

The stars of the Large Magellanic Cloud

Credit: ESA/Hubble & NASA


This NASA/ESA Hubble Space Telescope image shows the globular cluster NGC 1854, a gathering of white and blue stars in the southern constellation of Dorado (The Dolphinfish). NGC 1854 is located about 135 000 light-years away, in the Large Magellanic Cloud (LMC), one of our closest cosmic neighbours and a satellite galaxy of the Milky Way.

The LMC is a hotbed of vigorous star formation. Rich in interstellar gas and dust, the galaxy is home to approximately 60 globular clusters and 700 open clusters. These clusters are frequently the subject of astronomical research, as the Large Magellanic Cloud and its little sister, the Small Magellanic Cloud, are the only systems known to contain clusters at all stages of evolution. Hubble is often used to study these clusters as its extremely high-resolution cameras can resolve individual stars, even at the clusters’ crowded cores, revealing their mass, size and degree of evolution.



Thursday, June 23, 2016

Successful First Observations of Galactic Centre with GRAVITY

Artist’s impression of the star S2 passing very close to the supermassive black hole at the centre of the Milky Way

PR Image eso1622b
The centre of the Milky Way


Videos
 
Artist’s impression of the star S2 passing very close to the supermassive black hole at the centre of the Milky Way
Artist’s impression of the star S2 passing very close to the supermassive black hole at the centre of the Milky Way

Animation of the path of a light ray through GRAVITY
Animation of the path of a light ray through GRAVITY




Black hole probe now working with the four VLT Unit Telescopes

A European team of astronomers have used the new GRAVITY instrument at ESO’s Very Large Telescope to obtain exciting observations of the centre of the Milky Way by combining light from all four of the 8.2-metre Unit Telescopes for the first time. These results provide a taste of the groundbreaking science that GRAVITY will produce as it probes the extremely strong gravitational fields close to the central supermassive black hole and tests Einstein’s general relativity.

The GRAVITY instrument is now operating with the four 8.2-metre Unit Telescopes of ESO’s Very Large Telescope (VLT), and even from early test results it is already clear that it will soon be producing world-class science.

GRAVITY is part of the VLT Interferometer. By combining light from the four telescopes it can achieve the same spatial resolution and precision in measuring positions as a telescope of up to 130 metres in diameter. 

The corresponding gains in resolving power and positional accuracy — a factor of 15 over the individual 8.2-metre VLT Unit Telescopes — will enable GRAVITY to make amazingly accurate measurements of astronomical objects.

One of GRAVITY’s primary goals is to make detailed observations of the surroundings of the 4 million solar mass black hole at the very centre of the Milky Way [1]. Although the position and mass of the black hole have been known since 2002, by making precision measurements of the motions of stars orbiting it, GRAVITY will allow astronomers to probe the gravitational field around the black hole in unprecedented detail, providing a unique test of Einstein’s general theory of relativity.

In this regard, the first observations with GRAVITY are already very exciting. The GRAVITY team [2] has used the instrument to observe a star known as S2 as it orbits the black hole at the centre of our galaxy with a period of only 16 years. These tests have impressively demonstrated GRAVITY’s sensitivity as it was able to see this faint star in just a few minutes of observation.

The team will soon be able to obtain ultra-precise positions of the orbiting star, equivalent to measuring the position of an object on the Moon with centimetre precision. That will enable them to determine whether the motion around the black hole follows the predictions of Einstein’s general relativity — or not. The new observations show that the Galactic Centre is as ideal a laboratory as one can hope for.

"It was a fantastic moment for the whole team when the light from the star interfered for the first time — after eight years of hard work," says GRAVITY’s lead scientist Frank Eisenhauer from the Max Planck Institute for Extraterrestrial Physics in Garching, Germany. "First we actively stabilised the interference on a bright nearby star, and then only a few minutes later we could really see the interference from the faint star — to a lot of high-fives.” At first glance neither the reference star nor the orbiting star have massive companions that would complicate the observations and analysis. "They are ideal probes," explains Eisenhauer.

This early indication of success does not come a moment too soon. In 2018 the S2 star will be at its closest to the black hole, just 17 light-hours away from it and travelling at almost 30 million kilometres per hour, or 2.5% of the speed of light. At this distance the effects due to general relativity will be most pronounced and GRAVITY observations will yield their most important results [3]. This opportunity will not be repeated for another 16 years.
 


Notes

[1] The centre of the Milky Way, our home galaxy, lies on the sky in the constellation of Sagittarius (The Archer) and is some 25 000 light-years distant from Earth.

[2] The GRAVITY consortium consists of: the Max Planck Institutes for Extraterrestrial Physics (MPE) and Astronomy (MPIA), LESIA of Paris Observatory and IPAG of Université Grenoble Alpes/CNRS, the University of Cologne, the Centro Multidisciplinar de Astrofísica Lisbon and Porto (SIM), and ESO.

[3] The team will, for the first time, be able to measure two relativistic effects for a star orbiting a massive black hole — the gravitational redshift and the precession of the pericentre. The redshift arises because light from the star has to move against the strong gravitational field of the massive black hole in order to escape into the Universe. As it does so it loses energy, which manifests as a redshift of the light. The second effect applies to the star’s orbit and leads to a deviation from a perfect ellipse. The orientation of the ellipse rotates by around half a degree in the orbital plane when the star passes close to the black hole. The same effect has been observed for Mercury's orbit around the Sun, where it is about 6500 times weaker per orbit than in the extreme vicinity of the black hole. But the larger distance makes it much harder to observe in the Galactic Centre than in the Solar System.



More Information 


ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.



Links



Contacts

Frank Eisenhauer
GRAVITY Principal Investigator, Max Planck Institute for Extraterrestrial Physics
Garching, Germany
Tel: +49 (89) 30 000 3563
Email:
eisenhau@mpe.mpg.de

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email:
rhook@eso.org

Hannelore Hämmerle
Public Information Officer, Max Planck Institute for Extraterrestrial Physics
Garching, Germany
Tel: +49 (89) 30 000 3980
Email:
hannelore.haemmerle@mpe.mpg.de

Source: ESO

Writing their name in the stars: citizen scientists discover huge galaxy cluster

A radio contour overlay showing the newly-discovered Matorny-Terentev Cluster RGZ-CL J0823.2+0333. Credit: Banfield et al./SDSS.  


Two volunteer participants in an international citizen science project have had a rare galaxy cluster that they found named after them.

The pair pieced together the huge C-shaped structure from much smaller images of cosmic radio waves shown to them as part of the web-based program Radio Galaxy Zoo.

The discovery surprised the astronomers running the program, said the lead author of the study Dr Julie Banfield of the ARC Centre of Excellence for All-sky Astrophysics (CAASTRO) at The Australian National University (ANU).

“They found something that none of us had even thought would be possible,” said Dr Banfield.More than 10,000 volunteers have joined in with Radio Galaxy Zoo, classifying over 1.6 million images from NASA’s Wide-Field Infrared Survey Explorer telescope and the NRAO Very Large Array in New Mexico, USA.

“The dataset is just too big for any individual or small team to plough through – but we have already reached almost 60% completeness” said Dr Banfield.

The project is led by Dr Banfield and Dr Ivy Wong who is based at the International Centre for Radio Astronomy Research (ICRAR) at The University of Western Australia.

“Although radio astronomy is not as pretty as optical images from the Hubble space telescope, people can find cool things, like black holes, quasars, spiral galaxies or clusters of galaxies.”

The astronomers classified the newly-discovered feature as a wide angle tail (WAT) radio galaxy, named for the C-shaped tail shape of highly energetic jets of plasma which are being ejected from it.

It is part of a previously unreported sparsely-populated galaxy cluster and one of the biggest ever found.

Their discovery has now been published in the Monthly Notices of the Royal Astronomical Society with the two volunteers included as co-authors.

“This radio galaxy might have had two distinct episodes of activity during its lifetime, with quiet times of approximately 1 million years in between.” said Radio Galaxy Zoo science team member and co-author Dr Anna Kapinska, also of CAASTRO / ICRAR at the University of Western Australia. 

But the discovery of the Matorny-Terentev Cluster RGZ-CL J0823.2+0333, now bearing the names of the two citizen scientists, means even more than having added another piece to our cosmic puzzle.

While the unusual, bent shape of WATs has proven an excellent beacon for the detection of galaxy clusters, it will always be difficult to be detected by algorithms – which is where citizen science can play a huge part.

Through big projects such as Radio Galaxy Zoo, citizen science has established itself as a powerful research tool for astronomy, especially looking at the future challenges such as the EMU survey in Australia – the “Evolutionary Map of the Universe” with the Australian Square Kilometre Array Pathfinder (ASKAP) – and MeerKAT MIGHTEE in South Africa.

“Expanding on projects such as Radio Galaxy Zoo or on machine-learning techniques will be key to finding these unusual structures and to studying galaxy clusters.” said Dr Banfield.

The team of Radio Galaxy Zoo has entered their project in this year’s Australian Museum Eureka Prizes whose winners are expected to be announced during National Science Week.


Contact details

Dr Julie Banfield (ANU)
T: +61 2 6197 0171
M: 0415 753 414
Email: julie.banfield@anu.edu.au 

Dr Anna Kapinska (CAASTRO/ICRAR-UWA)
T: +61 8 6488 7748
M: 0474 476 790
Email: anna.kapinska@icrar.org 

Dr Ivy Wong (ICRAR-UWA)
T: +61 8 6488 7761
M: 0402 828 363
Email: ivy.wong@icrar.org


Multimedia  

Simulation of plasma jets - video courtesy of Brian O'Neill, Institute for Astrophysics, University of Minnesota

Wednesday, June 22, 2016

Astronomers Find the First 'Wind Nebula' Around a Magnetar

Astronomers have discovered a vast cloud of high-energy particles called a wind nebula around a rare ultra-magnetic neutron star, or magnetar, for the first time. The find offers a unique window into the properties, environment and outburst history of magnetars, which are the strongest magnets in the universe.  
 

A neutron star is the crushed core of a massive star that ran out of fuel, collapsed under its own weight, and exploded as a supernova. Each one compresses the equivalent mass of half a million Earths into a ball just 12 miles (20 kilometers) across, or about the length of New York's Manhattan Island. Neutron stars are most commonly found as pulsars, which produce radio, visible light, X-rays and gamma rays at various locations in their surrounding magnetic fields. When a pulsar spins these regions in our direction, astronomers detect pulses of emission, hence the name.

This illustration compares the size of a neutron star to Manhattan Island in New York, which is about 13 miles long. A neutron star is the crushed core left behind when a massive star explodes as a supernova and is the densest object astronomers can directly observe. Credits: NASA's Goddard Space Flight Center

Typical pulsar magnetic fields can be 100 billion to 10 trillion times stronger than Earth's. Magnetar fields reach strengths a thousand times stronger still, and scientists don't know the details of how they are created. Of about 2,600 neutron stars known, to date only 29 are classified as magnetars.

The newfound nebula surrounds a magnetar known as Swift J1834.9-0846 -- J1834.9 for short -- which was discovered by NASA's Swift satellite on Aug. 7, 2011, during a brief X-ray outburst. Astronomers suspect the object is associated with the W41 supernova remnant, located about 13,000 light-years away in the constellation Scutum toward the central part of our galaxy. 

"Right now, we don't know how J1834.9 developed and continues to maintain a wind nebula, which until now was a structure only seen around young pulsars," said lead researcher George Younes, a postdoctoral researcher at George Washington University in Washington. "If the process here is similar, then about 10 percent of the magnetar's rotational energy loss is powering the nebula’s glow, which would be the highest efficiency ever measured in such a system."

A month after the Swift discovery, a team led by Younes took another look at J1834.9 using the European Space Agency's (ESA) XMM-Newton X-ray observatory, which revealed an unusual lopsided glow about 15 light-years across centered on the magnetar. New XMM-Newton observations in March and October 2014, coupled with archival data from XMM-Newton and Swift, confirm this extended glow as the first wind nebula ever identified around a magnetar. A paper describing the analysis will be published by The Astrophysical Journal.

"For me the most interesting question is, why is this the only magnetar with a nebula? Once we know the answer, we might be able to understand what makes a magnetar and what makes an ordinary pulsar," said co-author Chryssa Kouveliotou, a professor in the Department of Physics at George Washington University’s Columbian College of Arts and Sciences.

The most famous wind nebula, powered by a pulsar less than a thousand years old, lies at the heart of the Crab Nebula supernova remnant in the constellation Taurus. Young pulsars like this one rotate rapidly, often dozens of times a second. The pulsar's fast rotation and strong magnetic field work together to accelerate electrons and other particles to very high energies. This creates an outflow astronomers call a pulsar wind that serves as the source of particles making up in a wind nebula.

The best-known wind nebula is the Crab Nebula, located about 6,500 light-years away in the constellation Taurus. At the center is a rapidly spinning neutron star that accelerates charged particles like electrons to nearly the speed of light. As they whirl around magnetic field lines, the particles emit a bluish glow. This image is a composite of Hubble observations taken in late 1999 and early 2000. The Crab Nebula spans about 11 light-years. Credits: NASA, ESA, J. Hester and A. Loll (Arizona State University)

"Making a wind nebula requires large particle fluxes, as well as some way to bottle up the outflow so it doesn't just stream into space," said co-author Alice Harding, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "We think the expanding shell of the supernova remnant serves as the bottle, confining the outflow for a few thousand years. When the shell has expanded enough, it becomes too weak to hold back the particles, which then leak out and the nebula fades away." This naturally explains why wind nebulae are not found among older pulsars, even those driving strong outflows.

A pulsar taps into its rotational energy to produce light and accelerate its pulsar wind. By contrast, a magnetar outburst is powered by energy stored in the super-strong magnetic field. When the field suddenly reconfigures to a lower-energy state, this energy is suddenly released in an outburst of X-rays and gamma rays. So while magnetars may not produce the steady breeze of a typical pulsar wind, during outbursts they are capable of generating brief gales of accelerated particles.

"The nebula around J1834.9 stores the magnetar's energetic outflows over its whole active history, starting many thousands of years ago," said team member Jonathan Granot, an associate professor in the Department of Natural Sciences at the Open University in Ra'anana, Israel. "It represents a unique opportunity to study the magnetar's historical activity, opening a whole new playground for theorists like me."

ESA's XMM-Newton satellite was launched on Dec. 10, 1999, from Kourou, French Guiana, and continues to make observations. NASA funded elements of the XMM-Newton instrument package and provides the NASA Guest Observer Facility at Goddard, which supports use of the observatory by U.S. astronomers.


Editor: Ashley Morrow


Tuesday, June 21, 2016

Boulevard of Broken Rings

Credit: ESO/Perrot


This Picture of the Week illustrates the remarkable capabilities of SPHERE (the Spectro-Polarimetric High-contrast Exoplanet REsearch instrument), a planet-hunting instrument mounted on ESO’s Very Large Telescope (VLT) in Chile: It shows a series of broken rings of dust around a nearby star. These concentric rings are located in the inner region of the debris disc surrounding a young star named HD 141569A, which sits some 370 light-years away from us.

In this image we see what is known as a transition disc, a short-lived stage between the protoplanetary phase, when planets have not yet formed, and a later time when planets have coalesced, leaving the disc populated only by any remaining — and predominantly dusty — debris.

What we see here are structures formed of dust, revealed for the first time in near-infrared light by SPHERE — at a high enough resolution to capture remarkable detail! The area shown in this image has a diameter of just 200 times the Earth–Sun distance.

Several features are visible, including a bright, prominent ring with well-defined edges — so asymmetric that it appears as a half-ring — multiple clumps, several concentric ringlets, and a pattern akin to a spiral arm. It is significant that these structures are asymmetric; this may reflect an uneven, or clumpy, distribution of dust in the disc, something for which astronomers do not currently have a firm explanation. It is possible that this phenomenon is caused by the presence of planets, but so far no planets of sufficient size to do this have been found in this system.

Links
  • Research paper — C. Perrot et al., Discovery of concentric broken rings at sub-arcsec separations in the HD 141569A gas-rich, debris disk with VLT/SPHERE.
 
Source: ESO/images

Monday, June 20, 2016

Venus has potential but not for water


Electric field at Venus
Copyright: ESA–C. Carreau


ESA’s Venus Express may have helped to explain the puzzling lack of water on Venus. The planet has a surprisingly strong electric field – the first time this has been measured at any planet – that is sufficient to deplete its upper atmosphere of oxygen, one of the components of water. 

Venus is often called Earth’s twin, since the second planet from the Sun is only slightly smaller than our own. 

But its atmosphere is quite different, consisting mainly of carbon dioxide, with a little nitrogen and trace amounts of sulphur dioxide and other gases. It is much thicker than Earth’s, reaching pressures of over 90 times that of Earth at sea level, and incredibly dry, with a relative abundance of water about 100 times lower than in Earth’s gaseous shroud. 

In addition, Venus now has a runaway greenhouse effect and a surface temperature high enough to melt lead. Also, unlike our home planet, it has no significant magnetic field of its own. 

Scientists think Venus did once host large amounts of water on its surface over 4 billion years ago. But as it heated up, much of this water evaporated into the atmosphere, where it could then be ripped apart by sunlight and subsequently lost to space. 

The solar wind – a powerful stream of charged subatomic particles blowing from the Sun – is one of the culprits, stripping hydrogen ions (protons) and oxygen ions from the planet’s atmosphere and so depriving it of the raw materials that make water.  

Now, scientists using Venus Express have identified another difference between the two planets: Venus has a substantial electric field, with a potential around 10 V. 

This is at least five times larger than expected. Previous observations in search of electric fields at Earth and Mars have failed to make a decisive detection, but they indicate that, if one exists, it is less than 2 V. 

“We think that all planets with atmospheres have a weak electric field, but this is the first time we have actually been able to detect one,” says Glyn Collinson from NASA’s Goddard Flight Space Center, lead author of the study. 

In any planetary atmosphere, protons and other ions feel a pull from the planet’s gravity. Electrons are much lighter and thus feel a smaller pull – they are able to escape the gravitational tug more easily. 

As the negative electrons drift upwards in the atmosphere and away into space, they are nevertheless still connected to the positive protons and ions via the electromagnetic force, and this results in an overall vertical electric field being created above the planet’s atmosphere. 

The electric field detected by Venus Express is much stronger than expected, and it can provide enough energy to oxygen ions to accelerate them upwards fast enough to escape the gravitational pull of the planet.

The discovery thus reveals another process, in addition to the solar wind stripping, that could contribute to the very low water content at Venus.

“The electric field of Venus is much stronger than we ever dreamed it could be, and really powerful if you’re as tiny as an oxygen ion,” adds Glyn.

“However, in real terms, the total power is only roughly the same as a single wind turbine, and it’s spread out over hundreds of kilometers of altitude, so as you can imagine, it’s incredibly hard to measure.”

The scientists patiently scrutinised two years’ data collected with an electron spectrometer, part of the ASPERA-4 instrument on Venus Express. They found 14 brief one-minute windows when the spacecraft was in just the right place with all the right conditions to measure an electric field. On every such occasion, the field was observed.

The reason why Venus has a much higher electric field than Earth is still under investigation. Glyn and his colleagues suspect that the planet’s closer position to the Sun might play a role.

“As it’s closer to the Sun than Earth, Venus receives twice as much ultraviolet light, which results in a higher number of free electrons in its atmosphere and, as a consequence, may cause a stronger electric field above the planet,” says Andrew Coates from Mullard Space Science Laboratory, UK, lead investigator of the ASPERA-4 electron spectrometer. 

The presence of such a field at Venus suggests that particles and ions necessary to form water are leaving the planet’s atmosphere faster than was expected. In turn, this means that Venus might have hosted even larger amounts of water in the past, before being almost entirely stripped away. 

“Water has a key role for life as we know it on Earth and possibly elsewhere in the Universe,” says Håkan Svedhem, Venus Express Project Scientist at ESA. 

“By suggesting a mechanism able to deprive a planet close to its parent star of most of its water, this discovery calls for a rethink of how we define a ‘habitable’ planet, not only in our Solar System, but also in the context of exoplanets.”

Notes for Editors


“The electric wind of Venus: A global and persistent “polar wind”-like ambipolar electric field sufficient for the direct escape of heavy ionospheric ions,” by G.A. Collinson et al. is published in Geophysical Research Letters

The study is based on data from the electron spectrometer, part of the ASPERA-4 instrument on Venus Express, which is led by Y. Futaana at the Swedish Institute of Space Physics in Kiruna, Sweden. 

ESA’s Venus Express was launched in 2005, arrived at Venus in 2006, and spent eight years exploring the planet from orbit. The mission ended in December 2014 after the spacecraft ran out of orbit-raising propellant and entered the atmosphere. 


For further information, please contact:

Glyn A. Collinson
NASA Goddard Space Flight Center
Greenbelt, Maryland, USA
Phone: +1 301 286 2511
Email:
glyn.a.collinson@nasa.gov

Andrew J. Coates
Mullard Space Science Laboratory
University College London, UK
Email:
a.coates@ucl.ac.uk

Håkan Svedhem
Venus Express Project Scientist
European Space Agency

Email: Hakan.Svedhem@esa.int

Markus Bauer








ESA Science Communication Officer









Tel: +31 71 565 6799









Mob: +31 61 594 3 954









Email:
markus.bauer@esa.int



Gravitational Waves Detected from Second Pair of Colliding Black Holes

This illustration shows the merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. The black holes—which represent those detected by LIGO on Dec. 26, 2015—were 14 and 8 times the mass of the sun, until they merged, forming a single black hole 21 times the mass of the sun. In reality, the area near the black holes would appear highly warped, and the gravitational waves would be difficult to see directly. Credit: LIGO/T. Pyle  


The LIGO Scientific Collaboration and the Virgo collaboration identify a second gravitational wave event in the data from Advanced LIGO detectors

On December 26, 2015 at 03:38:53 UTC, scientists observed gravitational waves—ripples in the fabric of spacetime—for the second time.

The gravitational waves were detected by both of the twin Laser Interferometer Gravitational-Wave Observatory (LIGO) detectors, located in Livingston, Louisiana, and Hanford, Washington, USA.

The LIGO Observatories are funded by the National Science Foundation (NSF), and were conceived, built, and are operated by Caltech and MIT. The discovery, accepted for publication in the journal Physical Review Letters, was made by the LIGO Scientific Collaboration (which includes the GEO Collaboration and the Australian Consortium for Interferometric Gravitational Astronomy) and the Virgo Collaboration using data from the two LIGO detectors.

Gravitational waves carry information about their origins and about the nature of gravity that cannot otherwise be obtained, and physicists have concluded that these gravitational waves were produced during the final moments of the merger of two black holes—14 and 8 times the mass of the sun—to produce a single, more massive spinning black hole that is 21 times the mass of the sun.

"It is very significant that these black holes were much less massive than those observed in the first detection," says Gabriela Gonzalez, LIGO Scientific Collaboration (LSC) spokesperson and professor of physics and astronomy at Louisiana State University. "Because of their lighter masses compared to the first detection, they spent more time—about one second—in the sensitive band of the detectors. It is a promising start to mapping the populations of black holes in our universe."

During the merger, which occurred approximately 1.4 billion years ago, a quantity of energy roughly equivalent to the mass of the sun was converted into gravitational waves. The detected signal comes from the last 27 orbits of the black holes before their merger. Based on the arrival time of the signals—with the Livingston detector measuring the waves 1.1 milliseconds before the Hanford detector—the position of the source in the sky can be roughly determined.

"In the near future, Virgo, the European interferometer, will join a growing network of gravitational wave detectors, which work together with ground-based telescopes that follow-up on the signals," notes Fulvio Ricci, the Virgo Collaboration spokesperson, a physicist at Istituto Nazionale di Fisica Nucleare (INFN) and professor at Sapienza University of Rome. "The three interferometers together will permit a far better localization in the sky of the signals."

The first detection of gravitational waves, announced on February 11, 2016, confirmed a major prediction of Albert Einstein's 1915 general theory of relativity, and marked the beginning of the new field of gravitational-wave astronomy.

The second discovery "has truly put the 'O' for Observatory in LIGO," says Caltech's Albert Lazzarini, deputy director of the LIGO Laboratory. "With detections of two strong events in the four months of our first observing run, we can begin to make predictions about how often we might be hearing gravitational waves in the future. LIGO is bringing us a new way to observe some of the darkest yet most energetic events in our universe."

"We are starting to get a glimpse of the kind of new astrophysical information that can only come from gravitational wave detectors," says MIT's David Shoemaker, who led the Advanced LIGO detector construction program.

Both discoveries were made possible by the enhanced capabilities of Advanced LIGO, a major upgrade that increases the sensitivity of the instruments compared to the first generation LIGO detectors, enabling a large increase in the volume of the universe probed.

"With the advent of Advanced LIGO, we anticipated researchers would eventually succeed at detecting unexpected phenomena, but these two detections thus far have surpassed our expectations," says NSF Director France A. Córdova. "NSF's 40-year investment in this foundational research is already yielding new information about the nature of the dark universe."

Advanced LIGO's next data-taking run will begin this fall. By then, further improvements in detector sensitivity are expected to allow LIGO to reach as much as 1.5 to 2 times more of the volume of the universe. The Virgo detector is expected to join in the latter half of the upcoming observing run.

LIGO research is carried out by the LIGO Scientific Collaboration (LSC), a group of more than 1,000 scientists from universities around the United States and in 14 other countries. More than 90 universities and research institutes in the LSC develop detector technology and analyze data; approximately 250 students are strong contributing members of the collaboration. The LSC detector network includes the LIGO interferometers and the GEO600 detector.

Virgo research is carried out by the Virgo Collaboration, consisting of more than 250 physicists and engineers belonging to 19 different European research groups: 6 from Centre National de la Recherche Scientifique (CNRS) in France; 8 from the Istituto Nazionale di Fisica Nucleare (INFN) in Italy; 2 in The Netherlands with Nikhef; the MTA Wigner RCP in Hungary; the POLGRAW group in Poland and the European Gravitational Observatory (EGO), the laboratory hosting the Virgo detector near Pisa in Italy.

The NSF provides most of the financial support for Advanced LIGO. Funding organizations in Germany (Max Planck Society), the U.K. (Science and Technology Facilities Council, STFC) and Australia (Australian Research Council) also have made significant commitments to the project.

Several of the key technologies that made Advanced LIGO so much more sensitive have been developed and tested by the German UK GEO collaboration. Significant computer resources have been contributed by the AEI Hannover Atlas Cluster, the LIGO Laboratory, Syracuse University, the ARCCA cluster at Cardiff University, the University of Wisconsin-Milwaukee, and the Open Science Grid. Several universities designed, built, and tested key components and techniques for Advanced LIGO: The Australian National University, the University of Adelaide, the University of Western Australia, the University of Florida, Stanford University, Columbia University in the City of New York, and Louisiana State University. The GEO team includes scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, AEI), Leibniz Universität Hannover, along with partners at the University of Glasgow, Cardiff University, the University of Birmingham, other universities in the United Kingdom and Germany, and the University of the Balearic Islands in Spain.

Contact: 

Whitney Clavin
(626) 390-9601
wclavin@caltech.edu

Source: Caltech/news

Saturday, June 18, 2016

Unexpected Excess of Giant Planets in Star Cluster

Artist’s impression of a hot Jupiter exoplanet in the star cluster Messier 67

The star cluster Messier 67 in the constellation of Cancer

Wide-field view of the open star cluster Messier 67 



Videos

Artist’s impression of hot Jupiter exoplanet in the star cluster Messier 67
Artist’s impression of hot Jupiter exoplanet in the star cluster Messier 67


An international team of astronomers have found that there are far more planets of the hot Jupiter type than expected in a cluster of stars called Messier 67. This surprising result was obtained using a number of telescopes and instruments, among them the HARPS spectrograph at ESO’s La Silla Observatory in Chile. The denser environment in a cluster will cause more frequent interactions between planets and nearby stars, which may explain the excess of hot Jupiters.

A Chilean, Brazilian and European team led by Roberto Saglia at the Max-Planck-Institut für extraterrestrische Physik, in Garching, Germany, and Luca Pasquini at ESO, has spent several years collecting high-precision measurements of 88 stars in Messier 67 [1]. This open star cluster is about the same age as the Sun and it is thought that the Solar System arose in a similarly dense environment [2].

The team used HARPS, along with other instruments [3], to look for the signatures of giant planets on short-period orbits, hoping to see the tell-tale “wobble” of a star caused by the presence of a massive object in a close orbit, a kind of planet known as a hot Jupiters. This hot Jupiter signature has now been found for a total of three stars in the cluster alongside earlier evidence for several other planets.

A hot Jupiter is a giant exoplanet with a mass of more than about a third of Jupiter’s mass. They are “hot” because they are orbiting close to their parent stars, as indicated by an orbital period (their “year”) that is less than ten days in duration. That is very different from the Jupiter we are familiar with in our own Solar System, which has a year lasting around 12 Earth- years and is much colder than the Earth [4].

We want to use an open star cluster as laboratory to explore the properties of exoplanets and theories of planet formation”, explains Roberto Saglia. “Here we have not only many stars possibly hosting planets, but also a dense environment, in which they must have formed.

The study found that hot Jupiters are more common around stars in Messier 67 than is the case for stars outside of clusters. “This is really a striking result,” marvels Anna Brucalassi, who carried out the analysis. “The new results mean that there are hot Jupiters around some 5% of the Messier 67 stars studied — far more than in comparable studies of stars not in clusters, where the rate is more like 1%.”

Astronomers think it highly unlikely that these exotic giants actually formed where we now find them, as conditions so close to the parent star would not initially have been suitable for the formation of Jupiter-like planets. Rather, it is thought that they formed further out, as Jupiter probably did, and then moved closer to the parent star. What were once distant, cold, giant planets are now a good deal hotter. The question then is: what caused them to migrate inwards towards the star?

There are a number of possible answers to that question, but the authors conclude that this is most likely the result of close encounters with neighbouring stars, or even with the planets in neighbouring solar systems, and that the immediate environment around a solar system can have a significant impact on how it evolves.

In a cluster like Messier 67, where stars are much closer together than the average, such encounters would be much more common, which would explain the larger numbers of hot Jupiters found there.

Co-author and co-lead Luca Pasquini from ESO looks back on the remarkable recent history of studying planets in clusters: “No hot Jupiters at all had been detected in open clusters until a few years ago. In three years the paradigm has shifted from a total absence of such planets — to an excess!



Notes

[1] Some of the original sample of 88 were found to be binary stars, or unsuitable for other reasons for this study. This new paper concentrates on a sub-group of 66 stars.

[2] Although the cluster Messier 67 is still holding together, the cluster that may have surrounded the Sun in its early years would have dissipated long ago, leaving the Sun on its own.

[3] Spectra from the High Resolution Spectrograph on the Hobby-Eberly Telescope in Texas, USA, were also used, as well as from the SOPHIE spectrograph at the Observatoire de Haute Provence, in France.

[4] The first exoplanet found around a star similar to the Sun, 51 Pegasi b, was also a hot Jupiter. This was a surprise at the time, as many astronomers had assumed that other planetary systems would probably be like the Solar System and have their more massive planets further from the parent star.


More Information

This research was presented in a paper entitled “Search for giant planets in M67 III: excess of Hot Jupiters in dense open clusters”, by A. Brucalassi et al., to appear in the journal Astronomy & Astrophysics.

The team consists of: A. Brucalassi (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; University Observatory Munich, Germany), L. Pasquini (ESO, Garching, Germany), R. Saglia (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany; University Observatory Munich, Germany), M.T. Ruiz (Universidad de Chile, Santiago, Chile), P. Bonifacio (GEPI, Observatoire de Paris, CNRS, Univ. Paris Diderot, Meudon, France), I. Leão (ESO, Garching, Germany; Universidade Federal do Rio Grande do Norte, Natal, Brazil), B.L. Canto Martins (Universidade Federal do Rio Grande do Norte, Natal, Brazil), J.R. de Medeiros (Universidade Federal do Rio Grande do Norte, Natal, Brazil), L. R. Bedin (INAF-Osservatorio Astronomico di Padova, Padova, Italy) , K. Biazzo (INAF-Osservatorio Astronomico di Catania, Catania, Italy), C. Melo (ESO, Santiago, Chile), C. Lovis (Observatoire de Geneve, Sauverny, Switzerland) and S. Randich (INAF-Osservatorio Astrofisico di Arcetri, Firenze, Italy).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.


 Links

Contacts

Anna Brucalassi
Max-Planck-Institut für extraterrestrische Physik
Garching bei München, Germany
Tel: +49 89 30000 3022
Email:
abrucala@mpe.mpg.de

Luca Pasquini
ESO
Garching bei München, Germany
Tel: +49 89 3200 6792
Email:
lpasquin@eso.org

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email:
rhook@eso.org

Hannelore Hämmerle
Max-Planck-Institut für extraterrestrische Physik
Garching bei München, Germany
Tel: +49 89 30 000 3980
Email:
hhaemmerle@mpa-garching.mpg.de


Source: ESO

Friday, June 17, 2016

ALMA Observes Most Distant Oxygen Ever

Schematic diagram of the history of the Universe

Colour composite image of a portion of the Subaru XMM-Newton Deep Survey Field

PR Image eso1620c
Colour composite image of distant galaxy SXDF-NB1006-2

Artist’s impression of the distant galaxy SXDF-NB1006-2


A team of astronomers has used the Atacama Large Millimeter/submillimeter Array (ALMA) to detect glowing oxygen in a distant galaxy seen just 700 million years after the Big Bang. This is the most distant galaxy in which oxygen has ever been unambiguously detected, and it is most likely being ionised by powerful radiation from young giant stars. This galaxy could be an example of one type of source responsible for cosmic reionisation in the early history of the Universe.

Astronomers from Japan, Sweden, the United Kingdom and ESO have used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe one of the most distant galaxies known. 

SXDF-NB1006-2 lies at a redshift of 7.2, meaning that we see it only 700 million years after the Big Bang.

The team was hoping to find out about the heavy chemical elements [1] present in the galaxy, as they can tell us about the level of star formation, and hence provide clues about the period in the history of the Universe known as cosmic reionisation.

Seeking heavy elements in the early Universe is an essential approach to explore the star formation activity in that period,” said Akio Inoue of Osaka Sangyo University, Japan, the lead author of the research paper, which is being published in the journal Science. “Studying heavy elements also gives us a hint to understand how the galaxies were formed and what caused the cosmic reionisation,” he added.

In the time before objects formed in the Universe, it was filled with electrically neutral gas. But when the first objects began to shine, a few hundred million years after the Big Bang, they emitted powerful radiation that started to break up those neutral atoms — to ionise the gas. During this phase — known as cosmic reionisation — the whole Universe changed dramatically. But there is much debate about exactly what kind of objects caused the reionisation. Studying the conditions in very distant galaxies can help to answer this question.

Before observing the distant galaxy, the researchers performed computer simulations to predict how easily they could expect to see evidence of ionised oxygen with ALMA. They also considered observations of similar galaxies that are much closer to Earth, and concluded that the oxygen emission should be detectable, even at vast distances [2].

They then carried out high-sensitivity observations with ALMA [3] and found light from ionised oxygen in SXDF-NB1006-2, making this the most distant unambiguous detection of oxygen ever obtained [4]. It is firm evidence for the presence of oxygen in the early Universe, only 700 million years after the Big Bang.

Oxygen in SXDF-NB1006-2 was found to be ten times less abundant than it is in the Sun. “The small abundance is expected because the Universe was still young and had a short history of star formation at that time,” commented Naoki Yoshida at the University of Tokyo. “Our simulation actually predicted an abundance ten times smaller than the Sun. But we have another, unexpected, result: a very small amount of dust.”

The team was unable to detect any emission from carbon in the galaxy, suggesting that this young galaxy contains very little un-ionised hydrogen gas, and also found that it contains only a small amount of dust, which is made up of heavy elements. “Something unusual may be happening in this galaxy,” said Inoue. “I suspect that almost all the gas is highly ionised.

The detection of ionised oxygen indicates that many very brilliant stars, several dozen times more massive than the Sun, have formed in the galaxy and are emitting the intense ultraviolet light needed to ionise the oxygen atoms.

The lack of dust in the galaxy allows the intense ultraviolet light to escape and ionise vast amounts of gas outside the galaxy. “SXDF-NB1006-2 would be a prototype of the light sources responsible for the cosmic reionisation,” said Inoue.

This is an important step towards understanding what kind of objects caused cosmic reionisation,” explained Yoichi Tamura of the University of Tokyo. “Our next observations with ALMA have already started. Higher resolution observations will allow us to see the distribution and motion of ionised oxygen in the galaxy and provide vital information to help us understand the properties of the galaxy.”


Notes

[1] In astronomical terminology, chemical elements heavier than lithium are known as heavy elements. 

[2] The Japanese infrared astronomy satellite AKARI had found that this oxygen emission is very bright in the Large Magellanic Cloud, which has an environment similar to the early Universe.


[3] The original wavelength of the light from doubly ionised oxygen is 0.088 millimetres. The wavelength of the light from SXDF-NB1006-2 is stretched to 0.725 millimetres by the expansion of the Universe, making the light observable with ALMA.

[4] Earlier work by Finkelstein et al. suggested the presence of oxygen at a slightly earlier time, but there was no direct detection of an emission line, as is the case in the new work.


More Information

This research was presented in the paper entitled: “Detection of an oxygen emission line from a high redshift galaxy in the reionization epoch” by Inoue et al., published in the journal Science.

The team is composed of: Akio Inoue (Osaka Sangyo University, Japan), Yoichi Tamura (The University of Tokyo, Japan), Hiroshi Matsuo (NAOJ/Graduate University for Advanced Studies, Japan), Ken Mawatari (Osaka Sangyo University, Japan), Ikkoh Shimizu (Osaka University, Japan), Takatoshi Shibuya (University of Tokyo, Japan), Kazuaki Ota (University of Cambridge, United Kingdom), Naoki Yoshida (University of Tokyo, Japan), Erik Zackrisson (Uppsala University, Sweden), Nobunari Kashikawa (NAOJ/Graduate University for Advanced Studies, Japan), Kotaro Kohno (University of Tokyo, Japan), Hideki Umehata (ESO, Garching, Germany; University of Tokyo, Japan), Bunyo Hatsukade (NAOJ, Japan), Masanori Iye (NAOJ, Japan), Yuichi Matsuda (NAOJ/Graduate University for Advanced Studies, Japan), Takashi Okamoto (Hokkaido University, Japan) and Yuki Yamaguchi (University of Tokyo, Japan).

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links

Contact

Akio Inoue
Osaka Sangyo University
Osaka, Japan
Email: akinoue@las.osaka-sandai.ac.jp

Masaaki Hiramatsu
NAOJ Chile Observatory EPO officer
Tel: +81 422 34 3630
Email: hiramatsu.masaaki@nao.ac.jp

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Cell: +49 151 1537 3591
Email: rhook@eso.org

Source: ESO