NICER’s Night Moves Trace the X-ray Sky

Credits: NASA/NICER.

In this image, numerous sweeping arcs seem to congregate at various bright regions. You may wonder: What is being shown? Air traffic routes? Information moving around the global internet? Magnetic fields looping across active areas on the Sun?

In fact, this is a map of the entire sky in X-rays recorded by NASA’s Neutron star Interior Composition Explorer (NICER), a payload on the International Space Station. NICER’s primary science goals require that it target and track cosmic sources as the station orbits Earth every 93 minutes. But when the Sun sets and night falls on the orbital outpost, the NICER team keeps its detectors active while the payload slews from one target to another, which can occur up to eight times each orbit.

The map includes data from the first 22 months of NICER’s science operations. Each arc traces X-rays, as well as occasional strikes from energetic particles, captured during NICER’s night moves. The brightness of each point in the image is a result of these contributions as well as the time NICER has spent looking in that direction. A diffuse glow permeates the X-ray sky even far from bright sources.

This image of the whole sky shows 22 months of X-ray data recorded by NASA's Neutron star Interior Composition Explorer (NICER) payload aboard the International Space Station during its nighttime slews between targets. NICER frequently observes targets best suited to its core mission (“mass-radius” pulsars) and those whose regular pulses are ideal for the Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) experiment. One day they could form the basis of a GPS-like system for navigating the solar system.  Credits: NASA/NICER. Download full-resolution images from NASA Goddard’s Scientific Visualization Studio 

The prominent arcs form because NICER often follows the same paths between targets. The arcs converge on bright spots representing NICER’s most popular destinations — the locations of important X-ray sources the mission regularly monitors.

“Even with minimal processing, this image reveals the Cygnus Loop, a supernova remnant about 90 light-years across and thought to be 5,000 to 8,000 years old,” said Keith Gendreau, the mission’s principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We’re gradually building up a new X-ray image of the whole sky, and it’s possible NICER’s nighttime sweeps will uncover previously unknown sources.”

NICER’s primary mission is to determine the size of dense remains of dead stars called neutron stars — some of which we see as pulsars — to a precision of 5%. These measurements will finally allow physicists to solve the mystery of what form of matter exists in their incredibly compressed cores. 

Pulsars, rapidly spinning neutron stars that appear to “pulse” bright light, are ideally suited to this “mass-radius” research and are some of NICER’s regular targets.

Other frequently visited pulsars are studied as part of NICER's Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) experiment, which uses the precise timing of pulsar X-ray pulses to autonomously determine NICER’s position and speed in space. It’s essentially a galactic GPS system. When mature, this technology will enable spacecraft to navigate themselves throughout the solar system — and beyond.

By Francis Reddy
NASA's Goddard Space Flight Center, Greenbelt, Md.


Media contact:  

Claire Andreoli
NASA's Goddard Space Flight Center, Greenbelt, Md.


Editor: Rob Garner

Source: NASA/NICER

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Subaru Telescope Captures 1800 Exploding Stars

Figure 1: Some supernovae discovered in this study. There are three images for each supernova for before it exploded (left), after it exploded (middle), and supernovae itself (difference of the first two images). (Credit: N. Yasuda et al.)  All images of supernovae discovered in this paper can be viewed here (Cooperated by Dr. Michitaro Koike of NAOJ).

Astronomers using the Subaru Telescope identified about 1800 new supernovae in the distant Universe, including 58 Type Ia supernovae over 8 billion light-years away. These findings will help elucidate the expansion of the Universe.

A supernova is the name given to an exploding star that has reached the end of its life. The star often becomes as bright as its host galaxy, shining one billion times brighter than the Sun for anytime between a month to six months before dimming down. Supernova classed as Type Ia are useful because their constant maximum brightness allows researchers to calculate how far the star is from Earth. This is particularly useful for researchers who want to measure the expansion of the Universe.

In recent years, researchers began reporting a new type of supernovae five to ten times brighter than Type Ia supernovae. Named Super Luminous Supernovae, many have been trying to learn more about these stars. Their unusual brightness enables researchers to spot stars in the farthest parts of the Universe usually too faint to observe. Since distant Universe means the early Universe, studying this kind of star could reveal characteristics about the first, massive stars created after the Big Bang.

But supernovae are rare events, and there are only a handful of telescopes in the world capable of capturing sharp images of distant stars. In order to maximize the chances of observing a supernova, a team led by Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) Professor Naoki Yasuda, and researchers from Tohoku University, Konan University, the National Astronomical Observatory of Japan, School of Science, the University of Tokyo, and Kyoto University, used the Subaru Telescope.

This telescope is capable of generating shape stellar images, and the Hyper Suprime-Cam, an 870 mega-pixel digital camera attached at its top, captures a very wide area of the night sky in one shot.

By taking repeated images of the same area of night sky over a six month period, the researchers could identify new supernovae by looking for stars that suddenly appeared brighter before gradually fading out.

As a result, the team identified 5 super luminous supernovae, and about 400 Type Ia supernovae. Fifty-eight of these Type Ia supernovae were located more than 8 billion light years away from Earth. In comparison, it took researchers using the Hubble Space Telescope about 10 years to discover a total of 50 supernovae located more than 8 billion light years away from Earth.

Figure 2: A map showing all of the supernovae (in red) discovered in this study. The blue circles indicate the areas Hyper Suprime-Cam was able to capture in one shot. The background is an image taken by the Sloan Digital Sky Survey. An image of the moon has been added to understand the area of night sky Hyper Suprime-Cam can capture. (Credit: Kavli IPMU, Partial data supplied by: SDSS)

"The Subaru Telescope and Hyper Suprime-Cam have already helped researchers create a 3D map of dark matter, and observation of primordial black holes, but now this result proves that this instrument has a very high capability finding supernovae very, very far away from Earth. I want to thank all of my collaborators for their time and effort, and look forward to analyzing our data to see what kind of picture of the Universe it holds," said Yasuda.

The next step will be to use the data to calculate a more accurate expansion of the Universe, and to study how dark energy has changed over time.

These results were published in Publications of the Astronomical Society of Japan (Yasuda et al., "The Hyper Suprime-Cam SSP Transient Survey in COSMOS: Overview"). A preprint is available here.

Links:

• Subaru Telescope captures 1800 exploding stars (Press Releases from the Kavli Institute for the Physics and Mathematics of the Universe)

 Source: Subaru Telescope

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A New View of Exoplanets With NASA’s Upcoming Webb Telescope

This illustration shows an exoplanet orbiting its much brighter star. With its onboard coronagraphs, Webb will allow scientists to view exoplanets at infrared wavelengths they’ve never seen them in before. Credits: NASA, ESA, and G. Bacon (STScI). Hi-res image

While we now know of thousands of exoplanets — planets around other stars — the vast majority of our knowledge is indirect. That is, scientists have not actually taken many pictures of exoplanets, and because of the limits of current technology, we can only see these worlds as points of light. However, the number of exoplanets that have been directly imaged is growing over time. When NASA’s James Webb Space Telescope launches in 2021, it will open a new window on these exoplanets, observing them in wavelengths at which they have never been seen before and gaining new insights about their nature.

Exoplanets are close to much brighter stars, so their light is generally overwhelmed by the light of the host stars. Astronomers usually find an exoplanet by inferring its presence based on the dimming of its host star’s light as the planet passes in front of the star – an event called a “transit.” Sometimes a planet tugs on its star, causing the star to wobble slightly.

Webb’s Unique Capabilities

Coronagraphs have something important in common with eclipses. During an eclipse, the Moon blocks the light of the Sun, allowing us to view stars that would normally be overwhelmed by the Sun’s glare. Astronomers took advantage of this during the 1919 eclipse, 100 years ago on May 29, in order to test Albert Einstein’s theory of general relativity. Similarly, a coronagraph acts as an “artificial eclipse” to block the light from a star, allowing planets that would otherwise be lost in the star’s glare to be seen.

“Most of the planets that we have detected so far are roughly 10,000 to 1 million times fainter than their host star,” explained Sasha Hinkley of the University of Exeter. Hinkley is the principal investigator on one of Webb’s first observation programs to study exoplanets and exoplanetary systems.

“There is, no doubt, a population of planets that are fainter than that, that have higher contrast ratios, and are possibly farther out from their stars,” Hinkley said. “With Webb, we will be able to see planets that are more like 10 million, or optimistically, 100 million times fainter.” To observe their targets, the team will use high-contrast imaging, which discerns this large difference in brightness between the planet and the star.

One of the targets Webb will study is the well-known, giant ring of dust and planetesimals orbiting a young star called HR 4796A. This Hubble Space Telescope photo shows a vast, complex dust structure, about 150 billion miles across, enveloping the young star HR 4796A. (The light from HR 4796A and its binary companion, HR 4796B, have been blocked to reveal the much dimmer dust structure.) A bright, narrow inner ring of dust encircling the star may have been corralled by the gravitational pull of an unseen giant planet. Credits: NASA, ESA, and G. Schneider (University of Arizona). Hi-res image

Webb will have the capability of observing its targets in the mid-infrared, which is invisible to the human eye, but with sensitivity that is vastly superior to any other observatory ever built. This means that Webb will be sensitive to a class of planet not yet detected. Specifically, Saturn-like planets at very wide orbital separations from their host star may be within reach of Webb.

“Our program is looking at young, newly formed planets and the systems they inhabit,” explained co-principal investigator Beth Biller of the University of Edinburgh. “Webb is going to allow us to do this in much more detail and at wavelengths we’ve never explored before. So it’s going to be vital for understanding how these objects form, and what these systems are like.”

Testing the Waters

The team’s observations will be part of the Director's Discretionary-Early Release Science program, which provides time to selected projects early in the telescope's mission. This program allows the astronomical community to quickly learn how best to use Webb's capabilities, while also yielding robust science.

“With our ERS program, we will really be ‘testing the waters’ to get an understanding of how Webb performs,” said Hinkley. “We really need the best understanding of the instruments, of the stability, of the most effective way to post-process the data. Our observations are going to tell our community the most efficient way to use Webb.”

This video illustrates the different methods scientists use to find exoplanets, or planets orbiting distant stars. 

Credits: NASA, ESA, and J. Olmsted (STScI)

The Targets

Hinkley’s team will use all four of Webb’s instruments to observe three targets: A recently discovered exoplanet; an object that is either an exoplanet or a brown dwarf; and a well-studied ring of dust and planetesimals orbiting a young star.

Exoplanet HIP 65426b: This newly discovered, directly imaged exoplanet has a mass between six and 12 times that of Jupiter and is orbiting a star that is hotter than and about twice as massive as our Sun. The exoplanet is roughly 92 times farther from its star than Earth is from the Sun. The wide separation of this young planet from its star means that the team’s observations will be much less affected by the bright glare of the host star. Hinkley and his team plan to use Webb’s full suite of coronagraphs to view this target.

Planetary-mass companion VHS 1256b: An object somewhere around the planet/brown dwarf boundary, VHS 1256b also is widely separated from its red dwarf host star—about 100 times the distance that the Earth is from the Sun. Because of its wide separation, observations of this object are much less likely to be affected by unwanted light from the host star. In addition to high-contrast imaging, the team expects to get one of the first "uncorrupted" spectra of a planet-like body at wavelengths where these objects have never before been studied.

Circumstellar debris disk: For more than 20 years, scientists have been studying a ring of dust and planetesimals orbiting a young star called HR 4796A, which is about twice as massive as our own Sun. Astronomers think that most planetary systems probably looked a lot like HR 4796A and its debris ring at their earliest ages, making this a particularly interesting target to study. The team will use the high-contrast imaging of Webb’s coronagraphs to view the disk in different wavelengths. Their goal is to see if the structures of the disk look different from wavelength to wavelength.

During an eclipse, the Moon blocks the light of the Sun, allowing us to view stars that would normally be overwhelmed by the Sun’s glare. Similarly, a coronagraph acts as an “artificial eclipse” to block the light from a star, allowing planets that would otherwise be lost in the star’s glare to be seen. Credits: NASA, ESA, and L. Hustak (STScI)

Planning the Program

To plan this Early Release Science program, Hinkley asked as many members of the astronomical community as possible the simple question: If you want to plan a survey to search for exoplanets, what are the questions that you need the answers to for planning your surveys?

“What we came up with was a set of observations that we think is going [to] answer those questions. We are going to tell the community that this is the way Webb performs in this mode, this is the kind of sensitivity we get, and this is the kind of contrast we achieve. And we need to rapidly turn that around and inform the community so that they can prepare their proposals really, really quickly.”

The team is excited to view their targets in wavelengths never before detected, and to share their knowledge. According to Biller, “We could see years ago that for some of the planets we’ve already discovered, Webb would be really transformational.” The James Webb Space Telescope will be the world’s premier space science observatory when it launches in 2021. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

For more information about Webb, visit:  www.nasa.gov/webb.

By Ann Jenkins

Space Telescope Science Institute, Baltimore Md.

Editor: Lynn Jenner

Source: NASA/Webb Telescope

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Star Formation in Young Galaxies Not Affected by Environment

Figure 1: Photo of the proto-cluster field from about 11 billion years ago (redshift z = 2.5) taken with MOIRCS on the Subaru Telescope. The insets are high-resolution narrow-band images of individual star-forming galaxies taken with IRCS+AO188. (Credit: NAOJ)

A team of astronomers used the Subaru Telescope to observe a proto-cluster of galaxies in the early Universe and found that the galaxies in it are forming stars in the same manner as isolated galaxies in the same era. This suggests that the galactic environment does not have a large influence on star formation in young galaxies.

Galaxies grow by forming new stars. By looking at where new stars are forming in young galaxies in the early Universe, astronomers can model how they will evolve into modern galaxies. A team led by Tomoko Suzuki, a post-doctoral researcher at Tohoku University, used the Subaru Telescope to observe a proto-cluster of galaxies from 11 billion years ago in the constellation Serpens. Using an Adaptive Optics (AO) system to correct for the blurring effect of Earth's atmosphere they successfully mapped the galaxies with a resolution of 0.2 arcsec (corresponding to 20/0.7 vision). Regions where young stars are forming are a different color than normal stars, so by using special filters to separate the colors, the team was able to observe both the stellar structure and the star-forming regions.

The observations show that on average for the more massive star-forming galaxies in the proto-cluster, the star-forming regions are more extended than the existing stellar structure. This means that the galaxies are growing by adding stars to their peripheries, rather than to their cores. This same pattern of star formation has been observed in isolated galaxies in sparsely populated regions in the same era. This result suggests that star formation in the early Universe is largely independent of galactic environment.

"The distribution of the star-forming region within galaxies is key information to understand the physical processes occurring in galaxies. We need to investigate not only the averaged structures but also the structure of the star-forming region within individual galaxies for more detailed studies." says Suzuki. "The next generation instrument ULTIMATE-Subaru will allow us to trace the individual structural growth of a large number of young galaxies in various environments."

These results will be published in Publications of the Astronomical Society of Japan (T. L. Suzuki, Y. Minowa, Y. Koyama, T. Kodama, M. Hayashi, R. Shimakawa, I. Tanaka, K.-i. Tadaki, "Extended star-forming region within galaxies in a dense proto-cluster core at z=2.53", 2019, Publications of the Astronomical Society of Japan, XX, XX). A preprint is available here. This study is supported by JSPS KAKENHI Grant Number JP18H03717.

Source: Subaru Telescope

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News Maunakea Observatories Help Shed New Light on Obscured Infant Solar System

LkCa 15

An expanded view of the central part of the cleared region around LkCa 15, showing a composite of two reconstructed images (blue: 2.1 microns, from November 2010; red: 3.7 microns) for LkCa 15. The location of the central star is also marked. Credit:Kraus & Ireland, 2011

Figure 1 – Keck Observatory/NIRC2 image of the Sun-like star LkCa 15 obtained from data taken in November 2009 and retrieved from the Keck Observatory Archive (top left) and taken in December 2017 (bottom-left). Both images show two arcs of light consistent with two components of LkCa 15’s circumstellar disk. The right panels show the 2009 and 2017 images of the innermost arc of light were three planets around LkCa 15. North is up and east is left in the images. The star is about 500 light-years from Earth. Light around LkCa 15 can be seen as close as ~9 au from the star (dark-blue masked region in the upper-right panel; Sun-to-Saturn distance); the innermost arc of light extends out to ~0.2” or ~30 au (Sun-to-Pluto distance). While the combined light from the simulated planets is blended, the NIRC2 data would show evidence of their orbital motion if the planets were present in these data. Analysis of Keck/NIRC2 data shows that most of the light around LkCa 15 comes from disk material instead of from planets. 

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W. M. Keck Observatory and Subaru Telescope Data Taken Over Eight Years Solve Planet Formation Mystery

Maunakea, Hawaii – Astronomers using the combined power of two Hawaii telescopes have taken groundbreaking, sharp new images of a distant planetary system that likely resembles a baby version of our solar system.

Using Subaru Telescope and W. M. Keck Observatory, the team obtained and analyzed data for an infant Sun-like star named LkCa 15. Previous studies using an advanced interferometry method had inferred that three infant planets were orbiting this star. However, for this method, determining exactly how much light comes from a planet versus other sources like a disk can be particularly difficult. New Subaru and Keck Observatory data appear to solve this mystery; most of the light thought to come from the three candidate planets appears to originate from a disk of gas and dust.

“LkCa 15 is a highly complex system,” said Thayne Currie, lead author of the study and astrophysicist at NASA-Ames Research Center and the Subaru Telescope. “Prior to analyzing our Keck & Subaru data and given the same prior aperture masking data, we also would have concluded that LkCa 15 has three detected superjovian planets.”

The team’s results will soon be published in The Astrophysical Journal Letters; a preprint is available here: https://arxiv.org/abs/1905.04322 .

LkCa 15 is surrounded by a massive protoplanetary disk made of gas and dust, which are the building blocks of planets. Early analysis of this disk showed it has a large cavity depleted of dust – a tell-tale sign that much of the disk material has already been incorporated into massive, developing planetary embryos, or “protoplanets.” While the study rules out very bright superjovian planets, Currie says it is likely that fainter, less massive planets may be in the LkCa 15 system: perhaps those like Jupiter and Saturn.

“The planets in this infant solar system could actually be a lot more like our own solar system than previously thought. They are certainly there somewhere, possibly embedded in the disk. We will keep trying to find them,” said Currie.

Methodology

The findings were made using high-resolution images of the LkCa 15 system obtained from complementary instruments on Maunakea. At Subaru, researchers used a new cutting-edge planet imaging instrument – the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system coupled to the CHARIS integral field spectrograph to obtain extremely sharp images at near-infrared wavelengths. The team also used Keck Observatory’s powerful adaptive optics system and Near-Infrared Camera (NIRC2) to obtain new sharp images at longer, thermal-infrared wavelengths where young planets emit more light.

The team also obtained a ‘before-and-after’ view of the system by accessing the Keck Observatory Archive (KOA) to find NIRC2 data taken for LkCa 15 from 2009 – over eight years before the most recent SCExAO/CHARIS and NIRC2 images. KOA is a publicly accessible repository of all the high-value data obtained at the Observatory and is operated by Keck Observatory in partnership with the NASA Exoplanet Science Institute (NExScI) at Caltech.

The combined data showed that most of the light surrounding LkCa 15 originates from an extended arc-like structure – the visible edge of another component of LkCa 15’s disk. This arc has the same brightness previously attributed to planets around LkCa 15. The nearly decade-old KOA data for LkCa 15 play a unique role in understanding this planetary system. When compared with new Keck Observatory and Subaru Telescope data, the KOA data also showed that light emitted from LkCa 15’s arc-like structure is static over the course of eight years.

“This is consistent with a fixed, disk-like structure. Without the KOA, we would not have been able to know this key fact,” said Currie.

“It’s great to see this new data from Keck and Subaru combined with data from the KOA,” said John O’Meara, chief scientist at Keck Observatory. “This result shows the importance of the KOA, and is a great demonstration of how new discoveries can be made with ‘old’ data.”

Source: W.M. Keck Observatory/Science News

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The Birth of the Hunter

NGC 2023
Credit: ESO

The constellation of Orion (The Hunter) is one of the most recognisable collections of stars in the night sky. We have noted Orion’s prominent stars for tens of thousands of years at least, and likely far longer. Chinese astronomers called it 参宿 or Shēn, literally “three stars”, for its three bright dots (which form the Hunter’s belt). The ancient Egyptians regarded it as the gods Sah and Sopdet, manifestations of Osiris and Isis, respectively, whereas Greek astronomers saw a brave hunter — the eponymous Orion — with his sword above his head, ready to strike.

Mythology aside, Orion is a fascinating patch of sky. This image, from ESO's Very Large Telescope, shows a reflection nebula nestled at the heart of the constellation — NGC 2023. Located close to the well-known Horsehead and Flame Nebulae, NGC 2023 lurks about 1500 light-years away from Earth, and is one of the largest reflection nebulae in the sky.

Reflection nebulae are clouds of interstellar dust that reflect the light from nearby or internal sources, like fog around a car headlight. NGC 2023 is illuminated by a massive young star named HD 37903. The star is extremely hot — several times hotter than the Sun — and its bright blue-white light causes NGC 2023’s milky glow. Such nebulae are often the birthplaces of stars, and contain a clumpy distribution of gas that’s significantly denser than the surrounding medium. Under the influence of gravity, these clumps attract one another and merge, eventually creating a new star. In a few million years time, Orion's Belt may gain a new star!

The image was taken with the VLT’s FORS (FOcal Reducer and Spectrograph) instrument as part of the ESO Cosmic Gems programme. This initiative produces images of interesting and visually attractive objects using ESO telescopes, for the purposes of education and outreach. The programme makes use of telescope time that cannot be used for science observations. All data collected may also be suitable for scientific purposes, and are made available to astronomers through ESO’s science archive.

Source: ESO/Potw

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Hubble Observes Creative Destruction as Galaxies Collide

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On the verge

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Distant view of a galactic crash — NGC 4490 and NGC 4485 (ground-based image)

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Videos

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Zoom-in on NGC 4485

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Pan on NGC 4485

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The NASA/ESA Hubble Space Telescope has taken a new look at the spectacular irregular galaxy NGC 4485, which has been warped and wound by its larger galactic neighbour. The gravity of the second galaxy has disrupted the ordered collection of stars, gas and dust, giving rise to an erratic region of newborn, hot, blue stars and chaotic clumps and streams of dust and gas.

The irregular galaxy NGC 4485 has been involved in a dramatic gravitational interplay with its larger galactic neighbour NGC 4490 — out of frame to the bottom right in this image. Found about 30 million light-years away in the constellation of Canes Venatici (the Hunting Dogs), the strange result of these interacting galaxies has resulted in an entry in the Atlas of Peculiar galaxies: Arp 269.

Having already made their closest approach, NGC 4485 and NGC 4490 are now moving away from each other, vastly altered from their original states. Still engaged in a destructive yet creative dance, the gravitational force between them continues to warp each of them out of all recognition, while at the same time creating the conditions for huge regions of intense star formation.

This galactic tug-of-war has created a stream of material about 25 000 light-years long which connects the two galaxies. The stream is made up of bright knots and huge pockets of gassy regions, as well as enormous regions of star formation in which young, massive, blue stars are born. Short-lived, however, these stars quickly run out of fuel and end their lives in dramatic explosions. While such an event seems to be purely destructive, it also enriches the cosmic environment with heavier elements and delivers new material to form a new generation of stars.

Two very different regions are now apparent in NGC 4485; on the left are hints of the galaxy’s previous spiral structure, which was at one time undergoing “normal” galactic evolution. The right of the image reveals a portion of the galaxy ripped towards its larger neighbour, bursting with hot, blue stars and streams of dust and gas.

This image, captured by the Wide Field Camera 3 (WFC3) on the Hubble Space Telescope, adds light through two new filters compared with an image released in 2014. The new data provide further insights into the complex and mysterious field of galaxy evolution.

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More Information

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.
Image credit: ESA, NASA

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Links

• Images of Hubble
• 2014 release of NGC 4485

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Contacts

Bethany Downer
ESA/Hubble, Public Information Officer
Garching, Germany
Email: bethany.downer@partner.eso.org

Source: ESA/Hubble/News

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A (simulated) Universe for Everybody – IllustrisTNG releases Petabyte data set

The TNG simulations model the univers from the large-scale cosmic structure right down to the substructure of galaxies

Image: Illustris-TNG

One of the largest and most detailed simulations of the cosmos has released most of its data to the public, as described in an article that has just been published.

The IllustrisTNG family of simulations is the closest astronomers have yet gotten to recreating a whole universe in a computer. These simulations include not only the ubiquitous Dark Matter, believed to be the most common form of matter in our cosmos, but gas in and between galaxies, stars, and even large-scale magnetic fields.

Now, in what is one of the largest astronomical data sets ever released, the IllustrisTNG team are making more than 1 Petabyte of their data available to the public. One Petabyte corresponds to 1000 Terabytes, or a million Gigabytes. Users can register at http://www.tng-project.org/data/ to obtain access to the data.

The IllustrisTNG simulation is special for the diversity of length scales it includes: Not only the largest possible structures in the cosmos, tens of millions of light-years, but details right down to the scale of structures within galaxies, less than a few thousand light-years. This makes for diverse applications within astronomy – from studies of the large-scale structure of the universe to studies of galaxy formation, star formation within galaxies, or the intergalactic medium.

The data release is accompanied by an accompanying article in the journal Computational Astrophysics and Cosmology, which has just been published. The current data release concerns the TNG300 and TNG100 data sets; the even more fine-grained simulation TNG50 will follow in due course. The data sets themselves have been available to the public since December 2018. The data is not only available for download, but can also be explored interactively, using a Google-Map-Like online interface and even a three-dimensional fly-through representation of the galactic halos within the IllustrisTNG universe, accessible at http://www.tng-project.org/explore/

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Links

• Illustris-TNG website
• TNG Data Exploration pages
• Article in Computational Astrophysics and Cosmology

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Science Contact

Annalisa Pillepich
Independent Research Group Leader
Phone: +49 6221 528-395
Email: pillepich@mpia-hd.mpg.de
Room: 121
Links: Personal homepage

PR Contact

Markus Pössel
Public Information Officer
Phone:+49 6221 528-261
Email: pr@mpia.de

Source: Max Planck Institute for Astronomy/News

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A Field of Galaxies Seen by Spitzer and Hubble

This deep-field view of the sky, taken by NASA's Spitzer Space Telescope, is dominated by galaxies - including some very faint, very distant ones - circled in red. The bottom right inset shows one of those distant galaxies, made visible thanks to a long-duration observation by Spitzer. The wide-field view also includes data from NASA's Hubble Space Telescope. The Spitzer observations came from the GREATS survey, short for GOODS Re-ionization Era wide-Area Treasury from Spitzer. GOODS is itself an acronym: Great Observatories Origins Deep Survey. NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology, also in Pasadena. Caltech manages JPL for NASA. The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. The Space Telescope Science Institute conducts Hubble science operations. The institute is operated for NASA by the Association of Universities for Research in Astronomy, Inc., Washington, D.C.  Credit NASA/JPL-Caltech/ESA/Spitzer/P. Oesch/S. De Barros/ I.Labbe 

This artist's illustration shows what one of the very first galaxies in the universe might have looked like. High levels of violent star formation and star death would have illuminated the gas filling the space between stars, making the galaxy largely opaque and without a clear structure. Credit: James Josephides (Swinburne Astronomy Productions)

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NASA's Spitzer Space Telescope has revealed that some of the universe's earliest galaxies were brighter than expected. The excess light is a byproduct of the galaxies releasing incredibly high amounts of ionizing radiation. The finding offers clues to the cause of the Epoch of Reionization, a major cosmic event that transformed the universe from being mostly opaque to the brilliant starscape seen today.

In a new study, researchers report on observations of some of the first galaxies to form in the universe, less than 1 billion years after the big bang (or a little more than 13 billion years ago). The data show that in a few specific wavelengths of infrared light, the galaxies are considerably brighter than scientists anticipated. The study is the first to confirm this phenomenon for a large sampling of galaxies from this period, showing that these were not special cases of excessive brightness, but that even average galaxies present at that time were much brighter in these wavelengths than galaxies we see today.

No one knows for sure when the first stars in our universe burst to life. But evidence suggests that between about 100 million and 200 million years after the big bang, the universe was filled mostly with neutral hydrogen gas that had perhaps just begun to coalesce into stars, which then began to form the first galaxies. By about 1 billion years after the big bang, the universe had become a sparkling firmament. Something else had changed, too: Electrons of the omnipresent neutral hydrogen gas had been stripped away in a process known as ionization. The Epoch of Reionization - the changeover from a universe full of neutral hydrogen to one filled with ionized hydrogen - is well documented.

Before this universe-wide transformation, long-wavelength forms of light, such as radio waves and visible light, traversed the universe more or less unencumbered. But shorter wavelengths of light - including ultraviolet light, X-rays and gamma rays - were stopped short by neutral hydrogen atoms. These collisions would strip the neutral hydrogen atoms of their electrons, ionizing them.

But what could have possibly produced enough ionizing radiation to affect all the hydrogen in the universe? Was it individual stars? Giant galaxies? If either were the culprit, those early cosmic colonizers would have been different than most modern stars and galaxies, which typically don't release high amounts of ionizing radiation. Then again, perhaps something else entirely caused the event, such as quasars - galaxies with incredibly bright centers powered by huge amounts of material orbiting supermassive black holes.

"It's one of the biggest open questions in observational cosmology," said Stephane De Barros, lead author of the study and a postdoctoral researcher at the University of Geneva in Switzerland. "We know it happened, but what caused it? These new findings could be a big clue."

Looking for Light

To peer back in time to the era just before the Epoch of Reionization ended, Spitzer stared at two regions of the sky for more than 200 hours each, allowing the space telescope to collect light that had traveled for more than 13 billion years to reach us.

As some of the longest science observations ever carried out by Spitzer, they were part of an observing campaign called GREATS, short for GOODS Re-ionization Era wide-Area Treasury from Spitzer. GOODS (itself an acronym: Great Observatories Origins Deep Survey) is another campaign that performed the first observations of some GREATS targets. The study, published in the Monthly Notices of the Royal Astronomical Society, also used archival data from NASA's Hubble Space Telescope.

Using these ultra-deep observations by Spitzer, the team of astronomers observed 135 distant galaxies and found that they were all particularly bright in two specific wavelengths of infrared light produced by ionizing radiation interacting with hydrogen and oxygen gases within the galaxies. This implies that these galaxies were dominated by young, massive stars composed mostly of hydrogen and helium. They contain very small amounts of "heavy" elements (like nitrogen, carbon and oxygen) compared to stars found in average modern galaxies.

These stars were not the first stars to form in the universe (those would have been composed of hydrogen and helium only) but were still members of a very early generation of stars. The Epoch of Reionization wasn't an instantaneous event, so while the new results are not enough to close the book on this cosmic event, they do provide new details about how the universe evolved at this time and how the transition played out.

"We did not expect that Spitzer, with a mirror no larger than a Hula-Hoop, would be capable of seeing galaxies so close to the dawn of time," said Michael Werner, Spitzer's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. "But nature is full of surprises, and the unexpected brightness of these early galaxies, together with Spitzer's superb performance, puts them within range of our small but powerful observatory."

NASA's James Webb Space Telescope, set to launch in 2021, will study the universe in many of the same wavelengths observed by Spitzer. But where Spitzer's primary mirror is only 85 centimeters (33.4 inches) in diameter, Webb's is 6.5 meters (21 feet) - about 7.5 times larger - enabling Webb to study these galaxies in far greater detail. In fact, Webb will try to detect light from the first stars and galaxies in the universe. The new study shows that due to their brightness in those infrared wavelengths, the galaxies observed by Spitzer will be easier for Webb to study than previously thought.

"These results by Spitzer are certainly another step in solving the mystery of cosmic reionization," said Pascal Oesch, an assistant professor at the University of Geneva and a co-author on the study. "We now know that the physical conditions in these early galaxies were very different than in typical galaxies today. It will be the job of the James Webb Space Telescope to work out the detailed reasons why."

JPL manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at Caltech in Pasadena. Space operations are based at Lockheed Martin Space Systems in Littleton, Colorado. Data are archived at the Infrared Science Archive housed at IPAC at Caltech. Caltech manages JPL for NASA.

News Media Contact

Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
626-808-2469
calla.e.cofield@jpl.nasa.gov

Source: JPL-Caltech/Spitzer/News

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Explosions of universe’s first stars spewed powerful jets

A simulation shows what the first supernovae could have looked like: Instead of spherical as many scientists have assumed, these brilliant explosions may have been asymmetric jets that shot heavy elements such as zinc (green dots) out into the early universe. This simulation shows the shape of the supernova, 50 seconds after the initial explosion.  Image: Melanie Gonick

Rana Ezzeddine and Anna Frebel of MIT have observed evidence that the first stars in the universe exploded as asymmetric supernova, strong enough to scatter heavy elements such as zinc across the early universe. Image: Melanie Gonick

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Instead of ballooning into spheres, as once thought, early supernovae ejected jets that may have seeded new stars.

Several hundred million years after the Big Bang, the very first stars flared into the universe as massively bright accumulations of hydrogen and helium gas. Within the cores of these first stars, extreme, thermonuclear reactions forged the first heavier elements, including carbon, iron, and zinc.

These first stars were likely immense, short-lived fireballs, and scientists have assumed that they exploded as similarly spherical supernovae.

But now astronomers at MIT and elsewhere have found that these first stars may have blown apart in a more powerful, asymmetric fashion, spewing forth jets that were violent enough to eject heavy elements into neighboring galaxies. These elements ultimately served as seeds for the second generation of stars, some of which can still be observed today.

In a paper published today in the Astrophysical Journal, the researchers report a strong abundance of zinc in HE 1327-2326, an ancient, surviving star that is among the universe’s second generation of stars. They believe the star could only have acquired such a large amount of zinc after an asymmetric explosion of one of the very first stars had enriched its birth gas cloud.

“When a star explodes, some proportion of that star gets sucked into a black hole like a vacuum cleaner,” says Anna Frebel, an associate professor of physics at MIT and a member of MIT’s Kavli Institute for Astrophysics and Space Research. “Only when you have some kind of mechanism, like a jet that can yank out material, can you observe that material later in a next-generation star. And we believe that’s exactly what could have happened here.”

“This is the first observational evidence that such an asymmetric supernova took place in the early universe,” adds MIT postdoc Rana Ezzeddine, the study’s lead author. “This changes our understanding of how the first stars exploded.”

“A sprinkle of elements”

HE 1327-2326 was discovered by Frebel in 2005. At the time, the star was the most metal-poor star ever observed, meaning that it had extremely low concentrations of elements heavier than hydrogen and helium — an indication that it formed as part of the second generation of stars, at a time when most of the universe’s heavy element content had yet to be forged.

“The first stars were so massive that they had to explode almost immediately,” Frebel says. “The smaller stars that formed as the second generation are still available today, and they preserve the early material left behind by these first stars. Our star has just a sprinkle of elements heavier than hydrogen and helium, so we know it must have formed as part of the second generation of stars.”

In May of 2016, the team was able to observe the star which orbits close to Earth, just 5,000 light years away. The researchers won time on NASA’s Hubble Space Telescope over two weeks, and recorded the starlight over multiple orbits. They used an instrument aboard the telescope, the Cosmic Origins Spectrograph, to measure the minute abundances of various elements within the star.

The spectrograph is designed with high precision to pick up faint ultraviolet light. Some of those wavelength are absorbed by certain elements, such as zinc. The researchers made a list of heavy elements that they suspected might be within such an ancient star, that they planned to look for in the UV data, including silicon, iron, phosophorous, and zinc.

“I remember getting the data, and seeing this zinc line pop out, and we couldn’t believe it, so we redid the analysis again and again,” Ezzeddine recalls. “We found that, no matter how we measured it, we got this really strong abundance of zinc.”

A star channel opens

Frebel and Ezzeddine then contacted their collaborators in Japan, who specialize in developing simulations of supernovae and the secondary stars that form in their aftermath. The researchers ran over 10,000 simulations of supernovae, each with different explosion energies, configurations, and other parameters. They found that while most of the spherical supernova simulations were able to produce a secondary star with the elemental compositions the researchers observed in HE 1327-2326, none of them reproduced the zinc signal.

As it turns out, the only simulation that could explain the star’s makeup, including its high abundance of zinc, was one of an aspherical, jet-ejecting supernova of a first star. Such a supernova would have been extremely explosive, with a power equivalent to about a nonillion times (that’s 10 with 30 zeroes after it) that of a hydrogen bomb.

“We found this first supernova was much more energetic than people have thought before, about five to 10 times more,” Ezzeddine says. “In fact, the previous idea of the existence of a dimmer supernova to explain the second-generation stars may soon need to be retired.”

The team’s results may shift scientists’ understanding of reionization, a pivotal period during which the gas in the universe morphed from being completely neutral, to ionized — a state that made it possible for galaxies to take shape.

“People thought from early observations that the first stars were not so bright or energetic, and so when they exploded, they wouldn’t participate much in reionizing the universe,” Frebel says. “We’re in some sense rectifying this picture and showing, maybe the first stars had enough oomph when they exploded, and maybe now they are strong contenders for contributing to reionization, and for wreaking havoc in their own little dwarf galaxies.”

These first supernovae could have also been powerful enough to shoot heavy elements into neighboring “virgin galaxies” that had yet to form any stars of their own.

“Once you have some heavy elements in a hydrogen and helium gas, you have a much easier time forming stars, especially little ones,” Frebel says. “The working hypothesis is, maybe second generation stars of this kind formed in these polluted virgin systems, and not in the same system as the supernova explosion itself, which is always what we had assumed, without thinking in any other way. So this is opening up a new channel for early star formation.”

This research was funded, in part, by the National Science Foundation.

Jennifer Chu | MIT News Office

Source: Massachusetts Institute of Technology - MIT/News

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Hubble Astronomers Assemble Wide View of the Evolving Universe

Image contains 265,000 galaxies that stretch billions of years back in time. 

Credits: NASA, ESA, and G. Illingworth (University of California, Santa Cruz; UCO/Lick Observatory)

Release Images

Astronomers have put together the largest and most comprehensive "history book" of galaxies into one single image, using 16 years' worth of observations from NASA's Hubble Space Telescope.

The deep-sky mosaic, created from nearly 7,500 individual exposures, provides a wide portrait of the distant universe, containing 265,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the big bang. The faintest and farthest galaxies are just one ten-billionth the brightness of what the human eye can see. The universe's evolutionary history is also chronicled in this one sweeping view. The portrait shows how galaxies change over time, building themselves up to become the giant galaxies seen in the nearby universe. 

This ambitious endeavor, called the Hubble Legacy Field, also combines observations taken by several Hubble deep-field surveys, including the eXtreme Deep Field (XDF), the deepest view of the universe. The wavelength range stretches from ultraviolet to near-infrared light, capturing the key features of galaxy assembly over time. 

"Now that we have gone wider than in previous surveys, we are harvesting many more distant galaxies in the largest such dataset ever produced by Hubble," said Garth Illingworth of the University of California, Santa Cruz, leader of the team that assembled the image. "This one image contains the full history of the growth of galaxies in the universe, from their time as 'infants' to when they grew into fully-fledged 'adults.' 

No image will surpass this one until future space telescopes are launched. "We've put together this mosaic as a tool to be used by us and by other astronomers," Illingworth added. "The expectation is that this survey will lead to an even more coherent, in-depth, and greater understanding of the universe's evolution in the coming years."

The image yields a huge catalog of distant galaxies. "Such exquisite high-resolution measurements of the numerous galaxies in this catalog enable a wide swath of extragalactic study," said catalog lead researcher Katherine Whitaker of the University of Connecticut, in Storrs. "Often, these kinds of surveys have yielded unanticipated discoveries which have had the greatest impact on our understanding of galaxy evolution."

Galaxies are the "markers of space," as astronomer Edwin Hubble once described them a century ago. Galaxies allow astronomers to trace the expansion of the universe, offer clues to the underlying physics of the cosmos, show when the chemical elements originated, and enable the conditions that eventually led to the appearance of our solar system and life.

This wider view contains about 30 times as many galaxies as in the previous deep fields. The new portrait, a mosaic of multiple snapshots, covers almost the width of the full Moon. The XDF, which penetrated deeper into space than this wider view, lies in this region, but it covers less than one-tenth of the full Moon's diameter. The Legacy Field also uncovers a zoo of unusual objects. Many of them are the remnants of galactic "train wrecks," a time in the early universe when small, young galaxies collided and merged with other galaxies. 

Assembling all of the observations was an immense task. The image comprises the collective work of 31 Hubble programs by different teams of astronomers. Hubble has spent more time on this tiny area than on any other region of the sky, totaling more than 250 days, representing nearly three-quarters of a year.

"Our goal was to assemble all 16 years of exposures into a legacy image," explained Dan Magee, of the University of California, Santa Cruz, the team's data processing lead. "Previously, most of these exposures had not been put together in a consistent way that can be used by any researcher. 

Astronomers can select the data in the Legacy Field they want and work with it immediately, as opposed to having to perform a huge amount of data reduction before conducting scientific analysis."

The image, along with the individual exposures that make up the new view, is available to the worldwide astronomical community through the Mikulski Archive for Space Telescopes (MAST). MAST, an online database of astronomical data from Hubble and other NASA missions, is located at the Space Telescope Science Institute in Baltimore, Maryland.

The Hubble Space Telescope has come a long way in taking ever deeper "core samples" of the distant universe. After Hubble's launch in 1990, astronomers debated if it was worth spending a chunk of the telescope's time to go on a "fishing expedition" to take a very long exposure of a small, seemingly blank piece of sky. The resulting Hubble Deep Field image in 1995 captured several thousand unseen galaxies in one pointing. The bold effort was a landmark demonstration and a defining proof-of-concept that set the stage for future deep field images. In 2002, Hubble's Advanced Camera for Surveys went even deeper to uncover 10,000 galaxies in a single snapshot. Astronomers used exposures taken by Hubble's Wide Field Camera 3 (WFC3), installed in 2009, to assemble the eXtreme Deep Field snapshot in 2012. Unlike previous Hubble cameras, the telescope's WFC3 covers a broader wavelength range, from ultraviolet to near-infrared.

This new image mosaic is the first in a series of Hubble Legacy Field images. The team is working on a second set of images, totaling more than 5,200 Hubble exposures, in another area of the sky. In the future, astronomers hope to broaden the multiwavelength range in the legacy images to include longer-wavelength infrared data and high-energy X-ray observations from two other NASA Great Observatories, the Spitzer Space Telescope and Chandra X-ray Observatory. 

The vast number of galaxies in the Legacy Field image are also prime targets for future telescopes. "This will really set the stage for NASA's planned Wide Field Infrared Survey Telescope (WFIRST)," Illingworth said. "The Legacy Field is a pathfinder for WFIRST, which will capture an image that is 100 times larger than a typical Hubble photo. In just three weeks' worth of observations by WFIRST, astronomers will be able to assemble a field that is much deeper and more than twice as large as the Hubble Legacy Field." 

In addition, NASA's upcoming James Webb Space Telescope will allow astronomers to push much deeper into the legacy field to reveal how the infant galaxies actually grew. Webb's infrared coverage will go beyond the limits of Hubble and Spitzer to help astronomers identify the first galaxies in the universe. 

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Hubble Legacy Field Video Zoom

The video begins with a view of the thousands of galaxies in the Hubble Ultra Deep Field and slowly zooms out to reveal the larger Hubble Legacy Field, containing 265,000 galaxies. Credits: NASA, ESA, G. Illingworth (University of California, Santa Cruz), and G. Bacon (STScI). Released video

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Related Links

• NASA's Hubble Portal
• Mikulski Archive for Space Telescopes (MAST)
• Hubble Legacy Field (HLF) in MAST
• ESA/Hubble's Release
• University of Connecticut's Release
• Yale University's Release
• University of California Santa Cruz's Release

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Contact 

Donna Weaver / Ray Villard
Space Telescope Science Institute, Baltimore, Maryland
410-338-4493 / 410-338-4514
dweaver@stsci.edu / villard@stsci.edu

Garth Illingworth
University of California, Santa Cruz; UCO/Lick Observatory, Santa Cruz, California
831-459-2843
gdi@ucolick.org

Source: HubbleSite/News

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Pinpointing Gaia to Map the Milky Way

PR Image eso1908a

Pinpointing Gaia to Map the Milky Way

PR Image eso1908b

Pinpointing Gaia to Map the Milky Way (Annotated)

PR Image eso1908c

Surveying the skies

PR Image eso1908d

The Gaia Spacecraft

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Gaia’s View of the Milky Way

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Videos

PR Video eso1908a

ESOcast 200 Light: ESO helps map the Galaxy

PR Video eso1908b

Animation of Gaia's Orbit

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ESO’s VST helps determine the spacecraft’s orbit to enable the most accurate map ever of more than a billion stars

This image, a composite of several observations captured by ESO’s VLT Survey Telescope (VST), shows the ESA spacecraft Gaia as a faint trail of dots across the lower half of the star-filled field of view. These observations were taken as part of an ongoing collaborative effort to measure Gaia’s orbit and improve the accuracy of its unprecedented star map.

Gaia, operated by the European Space Agency (ESA), surveys the sky from orbit to create the largest, most precise, three-dimensional map of our Galaxy. One year ago, the Gaia mission produced its much-awaited second data release, which included high-precision measurements — positions, distance and proper motions — of more than one billion stars in our Milky Way galaxy. This catalogue has enabled transformational studies in many fields of astronomy, addressing the structure, origin and evolution the Milky Way and generating more than 1700 scientific publications since its launch in 2013.

In order to reach the accuracy necessary for Gaia’s sky maps, it is crucial to pinpoint the position of the spacecraft from Earth. Therefore, while Gaia scans the sky, gathering data for its stellar census, astronomers regularly monitor its position using a global network of optical telescopes, including the VST at ESO’s Paranal Observatory [1]. The VST is currently the largest survey telescope observing the sky in visible light, and records Gaia’s position in the sky every second night throughout the year.

“Gaia observations require a special observing procedure,” explained Monika Petr-Gotzens, who has coordinated the execution of ESO’s observations of Gaia since 2013. “The spacecraft is what we call a ‘moving target’, as it is moving quickly relative to background stars — tracking Gaia is quite the challenge!”

“The VST is the perfect tool for picking out the motion of Gaia,” elaborated Ferdinando Patat, head of the ESO’s Observing Programmes Office. “Using one of ESO’s first-rate ground-based facilities to bolster cutting-edge space observations is a fine example of scientific cooperation.”

“This is an exciting ground-space collaboration, using one of ESO’s world-class telescopes to anchor the trailblazing observations of ESA’s billion star surveyor,” commented Timo Prusti, Gaia project scientist at ESA.

The VST observations are used by ESA’s flight dynamics experts to track Gaia and refine the knowledge of the spacecraft’s orbit. Painstaking calibration is required to transform the observations, in which Gaia is just a speck of light among the bright stars, into meaningful orbital information. Data from Gaia’s second release was used to identify each of the stars in the field of view, and allowed the position of the spacecraft to be calculated with astonishing precision — up to 20 milliarcseconds.

“This is a challenging process: we are using Gaia’s measurements of the stars to calibrate the position of the Gaia spacecraft and ultimately improve its measurements of the stars,” explains Timo Prusti

“After careful and lengthy data processing, we have now achieved the accuracy required for the ground-based observations of Gaia to be implemented as part of the orbit determination,” says Martin Altmann, lead of the Ground Based Optical Tracking (GBOT) campaign at the Centre for Astronomy of Heidelberg University, Germany.

The GBOT information will be used to improve our knowledge of Gaia’s orbit not only in observations to come, but also for all the data that have been gathered from Earth in the previous years, leading to improvements in the data products that will be included in future releases.

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Notes

[1] This collaboration between ESO and ESA is just one of several cooperative projects which have benefitted from the expertise of both organisations in progressing astronomy and astrophysics. On 20 August 2015, the ESA and ESO Directors General signed a cooperation agreement to facilitate synergy through projects such as these.

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More Information

In order to foster exchanges between astrophysics-related spaceborne missions and ground-based facilities, as well as between their respective communities, ESA and ESO are joining forces to organise a series of international astronomy meetings. The first ESA-ESO joint workshop will take place in November 2019 at ESO and a call for proposals for the second workshop, to take place in 2020 at ESA, is currently open.

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 16 Member States: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and with Australia as a Strategic Partner. 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 and its world-leading Very Large Telescope Interferometer as well as two survey telescopes, VISTA working in the infrared and the visible-light VLT Survey Telescope. Also at Paranal ESO will host and operate the Cherenkov Telescope Array South, the world’s largest and most sensitive gamma-ray observatory.

ESO is also a major partner in two facilities on Chajnantor, APEX and ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.

The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.

ESA is an international organisation with 22 Member States. By coordinating the financial and intellectual resources of its members, it can undertake programmes and activities far beyond the scope of any single European country.

ESA's Gaia satellite was launched in 2013 to create the most precise three-dimensional map of more than one billion stars in the Milky Way. The mission has released two lots of data thus far: Gaia Data Release 1 in 2016 and Gaia Data Release 2 in 2018. More releases will follow in the coming years.

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Links

• ESOblog: How ESO collaborates with ESA

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Contacts 

Calum Turner
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6670
Email: pio@eso.org

Source: ESO/News

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