Showing posts with label Carina Nebula. Show all posts
Showing posts with label Carina Nebula. Show all posts

Monday, December 19, 2022

NASA’s Webb Unveils Young Stars in Early Stages of Formation

Credits: Image: NASA, ESA, CSA, STScI
Science: Megan Reiter (Rice University)
Image Processing: Joseph DePasquale (STScI), Anton M. Koekemoer (STScI)

Unannotated, 2000 X 1079, PNG (2.77 MB)

Release Images



Scientists taking a “deep dive” into one of Webb’s iconic first images have discovered dozens of energetic jets and outflows from young stars previously hidden by dust clouds. The discovery marks the beginning of a new era of investigating how stars like our Sun form, and how the radiation from nearby massive stars might affect the development of planets.

The Cosmic Cliffs, a region at the edge of a gigantic, gaseous cavity within the star cluster NGC 3324, has long intrigued astronomers as a hotbed for star formation. While well-studied by the Hubble Space Telescope, many details of star formation in NGC 3324 remain hidden at visible-light wavelengths. Webb is perfectly primed to tease out these long-sought-after details since it is built to detect jets and outflows seen only in the infrared at high resolution. Webb’s capabilities also allow researchers to track the movement of other features previously captured by Hubble.

Recently, by analyzing data from a specific wavelength of infrared light (4.7 microns), astronomers discovered two dozen previously unknown outflows from extremely young stars revealed by molecular hydrogen. Webb’s observations uncovered a gallery of objects ranging from small fountains to burbling behemoths that extend light-years from the forming stars. Many of these protostars are poised to become low mass stars, like our Sun.

“What Webb gives us is a snapshot in time to see just how much star formation is going on in what may be a more typical corner of the universe that we haven’t been able to see before,” said astronomer Megan Reiter of Rice University in Houston, Texas, who led the study.

Molecular hydrogen is a vital ingredient for making new stars and an excellent tracer of the early stages of their formation. As young stars gather material from the gas and dust that surround them, most also eject a fraction of that material back out again from their polar regions in jets and outflows. These jets then act like a snowplow, bulldozing into the surrounding environment. Visible in Webb’s observations is the molecular hydrogen getting swept up and excited by these jets. “Jets like these are signposts for the most exciting part of the star formation process. We only see them during a brief window of time when the protostar is actively accreting,” explained co-author Nathan Smith of the University of Arizona in Tucson.

Previous observations of jets and outflows looked mostly at nearby regions and more evolved objects that are already detectable in the visual wavelengths seen by Hubble. The unparalleled sensitivity of Webb allows observations of more distant regions, while its infrared optimization probes into the dust-sampling younger stages. Together this provides astronomers with an unprecedented view into environments that resemble the birthplace of our solar system.

“It opens the door for what’s going to be possible in terms of looking at these populations of newborn stars in fairly typical environments of the universe that have been invisible up until the James Webb Space Telescope,” added Reiter. “Now we know where to look next to explore what variables are important for the formation of Sun-like stars.”

This period of very early star formation is especially difficult to capture because, for each individual star, it’s a relatively fleeting event – just a few thousand to 10,000 years amid a multi-million-year process of star formation.

“In the image first released in July, you see hints of this activity, but these jets are only visible when you embark on that deep dive – dissecting data from each of the different filters and analyzing each area alone,” shared team member Jon Morse of the California Institute of Technology in Pasadena. “It’s like finding buried treasure.”

In analyzing the new Webb observations, astronomers are also gaining insights into how active these star-forming regions are, even in a relatively short time span. By comparing the position of previously known outflows in this region caught by Webb, to archival data by Hubble from 16 years ago, the scientists were able to track the speed and direction in which the jets are moving.

This science was conducted on observations collected as part of Webb’s Early Release Observations Program. The paper was published in the Monthly Notices of the Royal Astronomical Society in December 2022.

The James Webb Space Telescope is the world's premier space science observatory. 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 CSA (Canadian Space Agency).




About This Release

Credits:

Release: NASA, ESA, CSA, STScI

Media Contact:

Hannah Braun
Space Telescope Science Institute, Baltimore, Maryland

Christine Pulliam
Space Telescope Science Institute, Baltimore, Maryland


Science Contact:

Megan Reiter
Rice University, Houston, Texas


Permissions: Content Use Policy

Contact Us: Direct inquiries to the News Team.

Related Links and Documents: Journal Article

Source: NASA's James Webb Space Telescope/News



Tuesday, October 06, 2020

Sharp: Most Detailed Image Yet of Famous Stellar Nursery

Carina Nebula western wall (with adaptive optics). A 50-trillion-km (33-trillion-mile, or 5 light-year) long section of the western wall in the Carina Nebula, as observed with adaptive optics on the Gemini South telescope. This mountainous section of the nebula reveals a number of unusual structures including a long series of parallel ridges that could be produced by a magnetic field, a remarkable almost perfectly smooth wave, and fragments that appear to be in the process of being sheared off the cloud by a strong wind. There is also evidence for a jet of material ejected from a newly-formed star. The exquisite detail seen in the image is in part due to a technology known as adaptive optics, which resulted in a ten-fold improvement in the resolution of the research team’s observations. Credit: International Gemini Observatory/NOIRLab/NSF/AURA. Acknowledgment: PI: Patrick Hartigan (Rice University). Image processing: Patrick Hartigan (Rice University), Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin.  download TIFF | JPEG

Comparison of images with and without Adaptive Optics (labeled). This image shows a comparison of the new image (top) of the western wall of the Carina Nebula taken by the international Gemini Observatory, a Program of NSF’s NOIRLab, and an image of the same region without Adaptive Optics (bottom). The top image was taken with the Gemini South telescope with the GSAOI instrument using the GeMS adaptive optics system, and the bottom image was taken at the Cerro Tololo Inter-American Observatory with the Víctor M. Blanco 4-meter Telescope using the NEWFIRM instrument. Credit: International Gemini Observatory/NOIRLab/NSF/AURA. Acknowledgment: PI: Patrick Hartigan (Rice University). Image processing: Patrick Hartigan (Rice University), Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin. download TIFF  JPEG

Carina Nebula Western Wall (labeled) A 50-trillion-km (33-trillion-mile, or 5 light-year) long section of the western wall in the Carina Nebula, as observed with adaptive optics on the Gemini South telescope. This mountainous section of the nebula reveals a number of unusual structures including a long series of parallel ridges that could be produced by a magnetic field, a remarkable almost perfectly smooth wave, and fragments that appear to be in the process of being sheared off the cloud by a strong wind. There is also evidence for a jet of material ejected from a newly-formed star. The exquisite detail seen in the image is in part due to a technology known as adaptive optics, which resulted in a ten-fold improvement in the resolution of the research team’s observations. Credit: International Gemini Observatory/NOIRLab/NSF/AURA. Acknowledgment: PI: Patrick Hartigan (Rice University). Image processing: Patrick Hartigan (Rice University), Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin.  download TIFF | JPEG

Looking Sharp: Most Detailed Image Yet of Famous Stellar Nursery.
Credit: Images and Videos: International Gemini Observatory/NOIRLab/NSF/AURA, NASA, D. Stover/ESO/S. Brunier/Digitized Sky Survey 2. Image Processing: Patrick Hartigan (Rice University), Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin. Music: Tomaz Vital - Auroras pt.2 (www.trilhavital.com). Video

The Carina Nebula observed in unprecedented detail with adaptive optics.

Astronomers using the international Gemini Observatory, a Program of NSF’s NOIRLab, have captured the western wall of the Carina Nebula in unprecedented detail in a compelling image released today. The image reveals a number of unusual structures in the nebula. The exquisite detail revealed in the image is in part due to a technology known as adaptive optics, which resulted in a ten-fold improvement in the sharpness of the research team’s observations.

There is no better location to investigate the birth of stars than nebulae — regions of gas and dust where stars coalesce, heat up and start to glow. The brilliant Carina Nebula, located in the southern hemisphere sky, is 500 times larger in actual area than the better-known Orion Nebula, making it an ideal candidate for investigating star formation.

The team used adaptive optics on the 8.1-meter Gemini South telescope in Chile to significantly improve upon previous observations of the Carina Nebula’s western wall, the well-defined edge of the nebula. Adaptive optics compensates for the effects of turbulence in the Earth’s atmosphere to produce pin-sharp images, comparable to those from a space telescope. Indeed, this image is reminiscent of the famous Hubble Pillars of Creation in the Eagle Nebula.

Star-forming regions are shrouded in dust but it is possible to see through the shroud of dust by observing in infrared light. The team, led by Patrick Hartigan of Rice University, utilized the Gemini South Adaptive Optics Imager (GSAOI), a near-infrared adaptive optics camera, to peer through the outer layers of dust to reveal a huge wall of dust and gas glowing with the intense ultraviolet light from nearby massive young stars. This region is a great example of such a wall and this image provides a very clear view of a star-forming region in the near-infrared [1].

With a resolution ten times higher than it would be without adaptive optics from the ground [2], the image reveals a wealth of detail never observed before. This mountainous section of the nebula reveals a number of unusual structures. There is a long series of parallel ridges that could be produced by a magnetic field, a remarkable almost perfectly smooth wave, and fragments that appear to be in the process of being sheared off the cloud by a strong wind. There is also evidence for a jet of material ejected from a newly-formed star.

The image provides the sharpest view to date of how massive young stars affect their surroundings and influence how star and planet formation proceeds. “It is possible that the Sun formed in such an environment,” said Hartigan. “If so, radiation and winds from any nearby massive stars would have affected the masses and atmospheres of the Solar System’s outer planets.” Astronomers are just beginning to model how such stars affect the evolution of planetary systems.

This spectacular image is a wonderful demonstration of the effectiveness of adaptive optics. It is also the first time that this region has been observed using this technique, so every new detail is a fascinating first glimpse for astronomers and the general public alike, and gives a taste of what could be possible with the upcoming James Webb Space Telescope.

Notes

[1] The region was examined at the infrared wavelength of molecular hydrogen (2120 nm). Molecular hydrogen is the best way to trace the structures because they would otherwise be rendered invisible by dust blocking them at optical and ultraviolet wavelengths (where the Hubble Space Telescope operates).

[2] The images are about twice as sharp as those from the Hubble Space Telescope at this wavelength.

More information

This research was presented in a paper published today in the Astrophysical Journal Letters.

The team is composed of Patrick Hartigan (Rice University), Turlough Downes (Dublin City University), Andrea Isella (Rice University).

Links

Contacts:

Amanda Kocz
Press and Internal Communications Officer
NSF’s NOIRLab
Cell: +1 626 524 5884
Email:
amanda.kocz@noirlab.edu

Source: Gemini Observatory


Wednesday, August 29, 2018

Stars v. Dust in the Carina Nebula

The Carina Nebula in infrared ligh
A wider view of the Carina Nebula

Digitized Sky Survey image of Eta Carinae Nebula

The Carina Nebula in the constellation of Carina



Videos
 
ESOcast 175 Light: Stars and Dust in the Carina Nebula (4K UHD)
ESOcast 175 Light: Stars and Dust in the Carina Nebula (4K UHD)

3D view of the Carina Nebula
3D view of the Carina Nebula

Zoom into the Carina Nebula
Zoom into the Carina Nebula

Pan across the Carina Nebula
Pan across the Carina Nebula



VISTA gazes into one of the largest nebulae in the Milky Way in infrared

The Carina Nebula, one of the largest and brightest nebulae in the night sky, has been beautifully imaged by ESO’s VISTA telescope at the Paranal Observatory in Chile. By observing in infrared light, VISTA has peered through the hot gas and dark dust enshrouding the nebula to show us myriad stars, both newborn and in their death throes.

About 7500 light-years away, in the constellation of Carina, lies a nebula within which stars form and perish side-by-side. Shaped by these dramatic events, the Carina Nebula is a dynamic, evolving cloud of thinly spread interstellar gas and dust.

The massive stars in the interior of this cosmic bubble emit intense radiation that causes the surrounding gas to glow. By contrast, other regions of the nebula contain dark pillars of dust cloaking newborn stars. There’s a battle raging between stars and dust in the Carina Nebula, and the newly formed stars are winning — they produce high-energy radiation and stellar winds which evaporate and disperse the dusty stellar nurseries in which they formed.

Spanning over 300 light-years, the Carina Nebula is one of the Milky Way's largest star-forming regions and is easily visible to the unaided eye under dark skies. Unfortunately for those of us living in the north, it lies 60 degrees below the celestial equator, so is visible only from the Southern Hemisphere.

Within this intriguing nebula, Eta Carinae takes pride of place as the most peculiar star system. This stellar behemoth — a curious form of stellar binary— is the most energetic star system in this region and was one of the brightest objects in the sky in the 1830s. It has since faded dramatically and is reaching the end of its life, but remains one of the most massive and luminous star systems in the Milky Way.

Eta Carinae can be seen in this image as part of the bright patch of light just above the point of the “V” shape made by the dust clouds. Directly to the right of Eta Carinae is the relatively small Keyhole Nebula — a small, dense cloud of cold molecules and gas within the Carina Nebula — which hosts several massive stars, and whose appearance has also changed drastically over recent centuries.

The Carina Nebula was discovered from the Cape of Good Hope by Nicolas Louis de Lacaille in the 1750s and a huge number of images have been taken of it since then. But VISTA — the Visible and Infrared Survey Telescope for Astronomy — adds an unprecedentedly detailed view over a large area; its infrared vision is perfect for revealing the agglomerations of young stars hidden within the dusty material snaking through the Carina Nebula. In 2014, VISTA was used to pinpoint nearly five million individual sources of infrared light within this nebula, revealing the vast extent of this stellar breeding ground. VISTA is the world’s largest infrared telescope dedicated to surveys and its large mirror, wide field of view and exquisitely sensitive detectors enable astronomers [1] to unveil a completely new view of the southern sky.



Notes
[1] The Principal Investigator of the observing proposal which led to this spectacular image was Jim Emerson (School of Physics & Astronomy, Queen Mary University of London, UK). His collaborators were Simon Hodgkin and Mike Irwin (Cambridge Astronomical Survey Unit, Cambridge University, UK). The data reduction was performed by Mike Irwin and Jim Lewis (Cambridge Astronomical Survey Unit, Cambridge University, UK).



More Information

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It has 15 Member States: Austria, Belgium, 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 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. 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”.



Links



Contacts

Jim Emerson
School of Physics & Astronomy, Queen Mary University of London
London, UK
Email: j.p.emerson@qmul.ac.uk

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


Source: ESO/News


Tuesday, March 27, 2018

Chaotic web of filaments in a Milky Way stellar nursery

Chaotic web of filaments in a Milky Way stellar nursery
Copyright ESA/Herschel/PACS, SPIRE/Hi-GAL Project. Acknowledgement: UNIMAP / L. Piazzo, La Sapienza - Università di Roma; E. Schisano / G. Li Causi, IAPS/INAF, Italy. Hi-res image


The plane of the Milky Way is rich in star-forming regions, such as the one pictured in this stunning scene by ESA’s Herschel space observatory. To the far-infrared eye of Herschel, this region reveals an intricate network of gas filaments and dark bubbles interspersed by bright hotspots where new stars come to life. 

The cooler regions, which emit light at longer wavelengths, are displayed in a red-brownish colour. Hotter areas, where star formation is more intense, shine in blue and white tones. Some areas are particularly bright, suggesting a number of luminous, massive stars are forming there.

Particularly striking is the chaotic web of gas filaments we see in this scene. Astronomers think there is a link between star formation and the filamentary structures in the interstellar medium. In the densest strands, the gas that makes up the filaments becomes unstable and forms clumps of material bound together by gravity. If dense enough, these collapsed blobs of gas eventually go on to become newborn stars.

Observations by Herschel showed the filamentary complexity to be ubiquitous in the plane of our Galaxy, from a few to hundreds of light-years. In nearby star-forming clouds, within 1500 light-years of the Sun, these filaments seem to be roughly all the same width – about a third of a light-year. This suggests a common physical mechanism in their origin, possibly linked to the turbulent nature of interstellar gas clouds.

The star-formation region in this image, centred around –70º longitude in galactic coordinates, is located in the Carina neighbourhood, home to the glorious Carina Nebula. Located some 7500 light-years away, Carina is one of the largest clouds of gas and dust in the plane of the Milky Way. It hosts the famous Eta Carinae, one of the most luminous and massive stellar systems in our galaxy. 

Herschel, which operated from 2009 until 2013, was a large space telescope observing in the far-infrared and submillimetre parts of the spectrum. This spectral range is ideal to observe the glow from cool dust in the regions where stars form. As part of Hi-GAL, the Herschel infrared Galactic Plane Survey, the observatory surveyed the plane of our Galaxy, exploring the Milky Way’s star-formation regions in unprecedented detail. This image, a product of Hi-GAL, combines observations at three different wavelengths: 70 microns (blue), 160 microns (green) and 250 microns (red).


Thursday, November 03, 2016

Pillars of Destruction

 PR Image eso1639a
Region R44 in the Carina Nebula 

Pillars of destruction
 
Region R18 in the Carina Nebula
 
Region R37 in the Carina Nebula
 
Region R45 in the Carina Nebula
 
Star cluster Trumpler 14
 
Bok Globule in the Carina Nebula
 
Mystic Mountain 



Videos

3D Animation of the Carina Nebula
3D Animation of the Carina Nebula

Zooming in on the Carina Nebula
Zooming in on the Carina Nebula



Colourful Carina Nebula blasted by brilliant nearby stars


Spectacular new observations of vast pillar-like structures within the Carina Nebula have been made using the MUSE instrument on ESO’s Very Large Telescope. The different pillars analysed by an international team seem to be pillars of destruction — in contrast to the name of the iconic Pillars of Creation in the Eagle Nebula, which are of similar nature.

The spires and pillars in the new images of the Carina Nebula are vast clouds of dust and gas within a hub of star formation about 7500 light-years away. The pillars in the nebula were observed by a team led by Anna McLeod, a PhD student at ESO, using the MUSE instrument on ESO’s Very Large Telescope.

The great power of MUSE is that it creates thousands of images of the nebula at the same time, each at a different wavelength of light. This allows astronomers to map out the chemical and physical properties of the material at different points in the nebula.

Images of similar structures, the famous Pillars of Creation [1] in the Eagle Nebula and formations in NGC 3603, were combined with the ones displayed here. In total ten pillars have been observed, and in so doing a clear link was observed between the radiation emitted by nearby massive stars and the features of the pillars themselves.

In an ironic twist, one of the first consequences of the formation of a massive star is that it starts to destroy the cloud from which it was born. The idea that massive stars will have a considerable effect on their surroundings is not new: such stars are known to blast out vast quantities of powerful, ionising radiation — emission with enough energy to strip atoms of their orbiting electrons. However, it is very difficult to obtain observational evidence of the interplay between such stars and their surroundings. <

The team analysed the effect of this energetic radiation on the pillars: a process known as photoevaporation, when gas is ionised and then disperses away. By observing the results of photoevaporation — which included the loss of mass from the pillars — they were able to deduce the culprits. There was a clear correlation between the amount of ionising radiation being emitted by nearby stars, and the dissipation of the pillars.

This might seem like a cosmic calamity, with massive stars turning on their own creators. However the complexities of the feedback mechanisms between the stars and the pillars are poorly understood. These pillars might look dense, but the clouds of dust and gas which make up nebulae are actually very diffuse. It is possible that the radiation and stellar winds from massive stars actually help create denser spots within the pillars, which can then form stars.

These breathtaking celestial structures have more to tell us, and MUSE is an ideal instrument to probe them with. 



Notes


[1] The Pillars of Creation are an iconic image, taken with the NASA/ESA Hubble Space Telescope, making them the most famous of these structures. Also known as elephant trunks, they can be several light-years in length.



More Information

This research was presented in a paper entitled “Connecting the dots: a correlation between ionising radiation and cloud mass-loss rate traced by optical integral field spectroscopy“, by A. F. McLeod et al., published in the Monthly Notices of the Royal Astronomical Society.

The team is composed of A. F. McLeod (ESO, Garching, Germany), M. Gritschneder (Universitäts-Sternwarte, Ludwig-Maximilians-Universität, Munich, Germany), J. E. Dale (Universitäts-Sternwarte, Ludwig-Maximilians-Universität, Munich, Germany), A. Ginsburg (ESO, Garching, Germany), P. D.Klaassen (UK Astronomy Technology Centre, Royal Observatory Edinburgh, UK), J. C. Mottram (Max Planck Institute for Astronomy, Heidelberg, Germany), T. Preibisch (Universitäts-Sternwarte, Ludwig-Maximilians-Universität, Munich, Germany), S. Ramsay (ESO, Garching, Germany), M. Reiter (University of Michigan Department of Astronomy, Ann Arbor, Michigan, USA) and L. Testi (ESO, Garching, Germany).

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”.



Link



Contacts

Anna Faye McLeod
ESO
Garching bei München, Germany
Tel: +49 89 3200 6321
Email:
amcleod@eso.org

Mathias Jäger
Public Information Officer
Garching bei München, Germany
Tel: +49 176 62397500

Source: ESO

Wednesday, October 19, 2016

Highest Resolution Image of Eta Carinae

Detailed look on Eta Carinae

Highest resolution image of Eta Carinae

Digitized Sky Survey Image of Eta Carinae Nebula

The Carina Nebula in the constellation of Carina 

Panoramic view of the WR 22 and Eta Carinae regions of the Carina Nebula*

One Picture, Many Stories

The Carina Nebula imaged by the VLT Survey Telescope 

Eta Carinae 



Videos

Zoom on Eta Carinae
Zoom on Eta Carinae

Animation of Eta Carinae and its surrounding
Animation of Eta Carinae and its surrounding





VLT Interferometer captures raging winds in famous massive stellar system


An international team of astronomers have used the Very Large Telescope Interferometer to image the Eta Carinae star system in the greatest detail ever achieved. They found new and unexpected structures within the binary system, including in the area between the two stars where extremely high velocity stellar winds are colliding. These new insights into this enigmatic star system could lead to a better understanding of the evolution of very massive stars.

Led by Gerd Weigelt from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, a team of astronomers have used the Very Large Telescope Interferometer (VLTI) at ESO’s Paranal Observatory to take a unique image of the Eta Carinae star system in the Carina Nebula.

This colossal binary system consists of two massive stars orbiting each other and is very active, producing stellar winds which travel at velocities of up to ten million kilometres per hour [1]. The zone between the two stars where the winds from each collide is very turbulent, but until now it could not be studied.

The power of the Eta Carinae binary pair creates dramatic phenomena. A “Great Eruption” in the system was observed by astronomers in the 1830s. We now know that this was caused by the larger star of the pair expelling huge amounts of gas and dust in a short amount of time, which led to the distinctive lobes, known as the Homunculus Nebula, that we see in the system today. The combined effect of the two stellar winds as they smash into each other at extreme speeds is to create temperatures of millions of degrees and intense deluges of X-ray radiation.

The central area where the winds collide is so comparatively tiny — a thousand times smaller than the Homunculus Nebula — that telescopes in space and on the ground so far have not been able to image them in detail. The team has now utilised the powerful resolving ability of the VLTI instrument AMBER to peer into this violent realm for the first time. A clever combination — an interferometer — of three of the four Auxiliary Telescopes at the VLT lead to a tenfold increase in resolving power in comparison to a single VLT Unit Telescope. This delivered the sharpest ever image of the system and yielded unexpected results about its internal structures.

The new VLTI image clearly depict the structure which exists between the two Eta Carinae-stars. An unexpected fan-shaped structure was observed where the raging wind from the smaller, hotter star crashes into the denser wind from the larger of the pair.

Our dreams came true, because we can now get extremely sharp images in the infrared. The VLTI provides us with a unique opportunity to improve our physical understanding of Eta Carinae and many other key objects”, says Gerd Weigelt.

In addition to the imaging, the spectral observations of the collision zone made it possible to measure the velocities of the intense stellar winds [2]. Using these velocities, the team of astronomers were able to produce more accurate computer models of the internal structure of this fascinating stellar system, which will help increase our understanding of how these kind of extremely high mass stars lose mass as they evolve.

Team member Dieter Schertl (MPIfR) looks forward: “The new VLTI instruments GRAVITY and MATISSE will allow us to get interferometric images with even higher precision and over a wider wavelength range. This wide wavelength range is needed to derive the physical properties of many astronomical objects.



Notes

[1] The two stars are so massive and bright that the radiation they produce rips off their surfaces and spews them into space. This expulsion of stellar material is referred to as stellar “wind”, and it can travel at millions of kilometres per hour.

[2] Measurements were done through the Doppler effect. Astronomers use the Doppler effect (or shifts) to calculate precisely how fast stars and other astronomical objects move toward or away from Earth. The movement of an object towards or away from us causes a slight shift in its spectral lines. The velocity of the motion can be calculated from this shift.



 More Information


This research was presented in a paper to appear in Astronomy and Astrophysics.

The team is composed of G. Weigelt (Max Planck Institute for Radio Astronomy, Germany), K.-H. Hofmann (Max Planck Institute for Radio Astronomy, Germany), D. Schertl (Max Planck Institute for Radio Astronomy, Germany), N. Clementel (South African Astronomical Observatory, South Africa) , M.F. Corcoran (Goddard Space Flight Center, USA; Universities Space Research Association, USA), A. Damineli (Universidade de São Paulo, Brazil ), W.-J. de Wit (European Southern Observatory, Chile), R. Grellmann (Universität zu Köln, Germany), J. Groh (The University of Dublin, Ireland ), S. Guieu (European Southern Observatory, Chile), T. Gull (Goddard Space Flight Center, USA), M. Heininger (Max Planck Institute for Radio Astronomy, Germany) , D.J. Hillier (University of Pittsburgh, USA), C.A. Hummel (European Southern Observatory, Germany), S. Kraus (University of Exeter, UK), T. Madura (Goddard Space Flight Center, USA), A. Mehner (European Southern Observatory, Chile), A. Mérand ( European Southern Observatory, Chile), F. Millour (Université de Nice Sophia Antipolis, France), A.F.J. Moffat (Université de Montréal, Canada), K. Ohnaka (Universidad Católica del Norte, Chile), F. Patru (Osservatorio Astrofisico di Arcetri, Italy), R.G. Petrov (Université de Nice Sophia Antipolis, France), S. Rengaswamy (Indian Institute of Astrophysics, India) , N.D. Richardson (The University of Toledo, USA), T. Rivinius (European Southern Observatory, Chile), M. Schöller (European Southern Observatory, Germany), M. Teodoro (Goddard Space Flight Center, USA) , and M. Wittkowski (European Southern Observatory, Germany)

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

Gerd Weigelt
Max-Planck-Institut für Radioastronomie
Bonn, Germany
Tel: +49 228 525 243
Email: weigelt@mpifr-bonn.mpg.de

Dieter Schertl
Max-Planck-Institut für Radioastronomie
Bonn, Germany
Tel: +49 228 525 301
Email: ds@mpifr-bonn.mpg.de

Norbert Junkes
Public Information Officer, Max-Planck-Institut für Radioastronomie
Bonn, Germany
Tel: +49 228 525 399
Email: njunkes@mpifr-bonn.mpg.de

Mathias Jäger
Public Information Officer
Garching bei München, Germany
Tel: +49 176 62397500
Email: mjaeger@partner.eso.org

Source: ESO

Thursday, December 06, 2012

Image of the Carina Nebula Marks Inauguration of VLT Survey Telescope

 
 PR Image eso1250a
The Carina Nebula imaged by the VLT Survey Telescope

 PR Image eso1250b
The VST inauguration

  PR Image eso1250c
President Sebastián Piñera of Chile in the Paranal Control Room

PR Image eso1250d
The Carina Nebula in the constellation of Carina

   PR Image eso1250e
Digitized Sky Survey Image of Eta Carinae Nebula

Videos

PR Video eso1250a
Zooming in on the Carina Nebula

PR Video eso1250b
Panning across a VST image of the Carina Nebula

A spectacular new image of the star-forming Carina Nebula has been captured by the VLT Survey Telescope at ESO’s Paranal Observatory and released on the occasion of the inauguration of the telescope in Naples today. This picture was taken with the help of Sebastián Piñera, President of Chile, during his visit to the observatory on 5 June 2012.

The latest telescope at ESO's Paranal Observatory in Chile — the VLT Survey Telescope (VST) — was inaugurated today at the Italian National Institute for Astrophysics (INAF) Observatory of Capodimonte, in Naples, Italy. The ceremony was attended by the Mayor of Naples, Luigi De Magistris, the INAF President, Giovanni Bignami, the ESO representatives Bruno Leibundgut and Roberto Tamai, and the main promoter of the telescope, Massimo Capaccioli of the University of Naples Federico II and INAF.

The VST is a state-of-the-art 2.6-metre telescope, with the huge 268-megapixel camera OmegaCAM at its heart. It is designed to map the sky both quickly and with very fine image quality. The VST is a joint venture between ESO and INAF and OmegaCam has been provided by the OmegaCam consortium [1]. This new telescope is the largest telescope in the world exclusively dedicated to surveying the sky at visible wavelengths (eso1119). The occasion of the inauguration has been marked by the release of a dramatic picture of the Carina Nebula taken with the new telescope.

This star formation region is one of the most prominent and frequently imaged objects of the southern sky. It has been the subject of many earlier images with ESO telescopes (eso1208, eso1145, eso1031, eso0905). However, the glowing gas cloud is huge and it is difficult for most large telescopes to study more than a tiny part of it at once. This makes it an ideal target for the VLT Survey Telescope and its big camera, OmegaCAM. The VST delivers very sharp images because of its high quality optics and the excellent site. But, as it was designed for surveys of the sky, it also has a very wide field of view that can take in almost all of the Carina Nebula in a single picture.

This object was a natural target when the President of Chile, Sebastián Piñera, accompanied by the First Lady, Cecilia Morel, were distinguished guests at the Paranal Observatory on 5 June 2012 (eso1223) and participated in observations with the VST. The picture that the President helped to take on this occasion has now been combined with other recent VST images of the Carina Nebula to produce one of the most richly detailed and colourful views of this object ever created.

The Carina Nebula is a huge stellar nursery lying about 7500 light-years from Earth in the constellation of Carina (The Keel) [2]. This cloud of glowing gas and dust is one of the closest star formation regions to the Earth and includes several of the brightest and most massive stars known. The Carina Nebula is a perfect laboratory for astronomers studying the violent births and early lives of stars.

The conspicuous red colour of the picture comes from hydrogen gas in the nebula that is glowing under the harsh ultraviolet light from many young and hot stars [3]. Other colours, originating from other elements in the gas, are also visible, as well as many dust clouds. Just above the centre of the picture lies the bright star Eta Carinae (eso0817). This huge and highly unstable star brightened dramatically in the nineteenth century and is a good candidate for a future supernova explosion.

Notes

[1] The VST programme was a joint venture between the INAF–Osservatorio Astronomico di Capodimonte, Naples, Italy and ESO. INAF designed and built the telescope with the collaboration of leading Italian industries and ESO was responsible for the enclosure and the civil engineering works at the site. OmegaCAM, the VST’s camera, was designed and built by a consortium including institutes in the Netherlands, Germany and Italy with major contributions from ESO. The new facility is operated by ESO, which also archives and distributes data from the telescope. For further details please refer to eso1119.

[2] Carina is the keel of the mythological ship Argo, of Jason and the Argonauts fame.

[3] The special filter for observing hydrogen emission was kindly made available by the VPHAS+ Consortium.

More information

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive astronomical observatory. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 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 the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links

Contacts

 Massimo Capaccioli
 University of Naples Federico II and INAF-Capodimonte Astronomical Observatory
 Naples, Italy
 Tel: +39 081 557 5601
 Cell: +39 335 677 6940
 Email:
capaccioli@na.infn.it

 Richard Hook
 ESO, La Silla, Paranal, E-ELT & Survey Telescopes Press Officer
 Garching bei München, Germany
 Tel: +49 89 3200 6655
 Cell: +49 151 1537 3591
 Email:
rhook@eso.org

Monday, June 04, 2012

Blowing bubbles in the Carina Nebula

The Carina Nebula, by ESA’s Herschel space observatory. The image shows the effects of massive star formation – powerful stellar winds and radiation have carved pillars and bubbles in dense clouds of gas and dust.

The image covers approximately 2.3 x 2.3 degrees of the Carina Nebula complex and was mapped using Herschel instruments PACS and SPIRE at wavelengths of 70, 160, and 250 microns, corresponding to the blue, green, and red channels, respectively. North is to the upper left and east is to the lower left.

Credits: ESA/PACS/SPIRE/Thomas Preibisch, Universitäts-Sternwarte München, Ludwig-Maximilians-Universität München, Germany. HI-RES JPEG (Size: 1429 kb)

Giant bubbles, towering pillars and cascading clouds of dust and gas fill the star-forming nursery of the Carina Nebula seen here in a stunning new view from Herschel to launch ESA Space Science’s image of the week feature.

The Carina Nebula is some 7500 lightyears from Earth and hosts some of the most massive and luminous stars in our Galaxy, including double-star system eta Carinae, which boasts over 100 times the mass of our Sun.

The total amount of gas and dust traced by ESA’s Herschel space observatory in this image is equivalent to some 650 000 Suns. Including warmer gas not well traced by Herschel, the total mass may be as high as 900 000 Suns.

Surrounding pillars of gas and dust point towards the bright central region of nebulosity – home to eta Carinae and numerous other massive stars.

The pillars are carved by intense stellar winds and radiation blasted out by these stars, eating away at the surrounding material.

Above and to the left is a chaotic web of bubbles and broken bubble arcs molded by individual regions of star formation that have swept up shells of dense clouds around them.

At top right is the Gum 31 nebula, which has blown a giant bubble out of the surrounding dense clouds thanks to winds and radiation emitted by the young stellar cluster NGC 3324 that sits at its heart.

This latest Herschel image launches ESA Space Science’s new image of the week series, which will present a variety of images and animations capturing all aspects of space science from the Sun, planets, stars, and galaxies to the edge of the Universe, along with the spacecraft that provide us with these spectacular views.

Every week, look to the top right of the Space Science homepage and prepare to be amazed!

For further information, please contact:

Markus Bauer
ESA Science and Robotic Exploration Communication Officer
Tel: +31 71 565 6799
Mob: +31 61 594 3 954
Email: markus.bauer@esa.int

Göran Pilbratt
ESA Herschel Project Scientist
Research and Scientific Support Department
Science and Robotic Exploration Directorate
ESA, The Netherlands
Tel: +31 71 565 3621
Email: gpilbratt@rssd.esa.int

Wednesday, February 15, 2012

Astronomers Watch Delayed Broadcast of a Powerful Stellar Eruption

Carina Nebula
Credit:NASA,NOAO, and A. Rest (Space Telescope Science Institute, Baltimore, Md.)
Acknowledgment: NOAO,AURA, NSF, and N. Smith (University of Arizona)

Astronomers are watching a delayed broadcast of a spectacular outburst from the unstable, behemoth double-star system Eta Carinae, an event initially seen on Earth nearly 170 years ago.

Dubbed the "Great Eruption," the outburst first caught the attention of sky watchers in 1837 and was observed through 1858. But astronomers didn't have sophisticated science instruments to accurately record the star system's petulant activity.

Luckily for today's astronomers, some of the light from the eruption took an indirect path to Earth and is just arriving now, providing an opportunity to analyze the outburst in detail. The wayward light was heading in a different direction, away from our planet, when it bounced off dust clouds lingering far from the turbulent stars and was rerouted to Earth, an effect called a "light echo." Because of its longer path, the light reached Earth 170 years later than the light that arrived directly.

The observations of Eta Carinae's light echo are providing new insight into the behavior of powerful massive stars on the brink of detonation. The views of the nearby erupting star reveal some unexpected results, which will force astronomers to modify physical models of the outburst.

"When the eruption was seen on Earth 170 years ago, there were no cameras capable of recording the event," explained the study's leader, Armin Rest of the Space Telescope Science Institute in Baltimore, Md. "Everything astronomers have known to date about Eta Carinae's outburst is from eyewitness accounts. Modern observations with science instruments were made years after the eruption actually happened. It's as if nature has left behind a surveillance tape of the event, which we are now just beginning to watch. We can trace it year by year to see how the outburst changed."

The team's paper will appear Feb. 16 in a letter to the journal Nature.

Located 7,500 light-years from Earth, Eta Carinae is one of the largest and brightest star systems in our Milky Way galaxy. Although the chaotic duo is known for its petulant outbursts, the Great Eruption was the biggest ever observed. During the 20-year episode, Eta Carinae shed some 20 solar masses and became the second brightest star in the sky. Some of the outflow formed the system's twin giant lobes. Before the epic event, the stellar pair was 140 times heftier than our Sun.

Because Eta Carinae is relatively nearby, astronomers have used a variety of telescopes, including the Hubble Space Telescope, to document its escapades. The team's study involved a mix of visible-light and spectroscopic observations from ground-based telescopes.

The observations mark the first time astronomers have used spectroscopy to analyze a light echo from a star undergoing powerful recurring eruptions, though they have measured this unique phenomenon around exploding stars called supernovae. Spectroscopy captures a star's "fingerprints," providing details about its behavior, including the temperature and speed of the ejected material.

The delayed broadcast is giving astronomers a unique look at the outburst and turning up some surprises. The turbulent star system does not behave like other stars of its class. Eta Carinae is a member of a stellar class called Luminous Blue Variables, large, extremely bright stars that are prone to periodic outbursts. The temperature of the outflow from Eta Carinae's central region, for example, is about 8,500 degrees Fahrenheit (5,000 Kelvin), which is much cooler than that of other erupting stars. "This star really seems to be an oddball," Rest said. "Now we have to go back to the models and see what has to change to actually produce what we are measuring."

Rest's team first spotted the light echo while comparing visible-light observations he took of the stellar duo in 2010 and 2011 with the U.S. National Optical Astronomy Observatory's Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory (CTIO) in Chile. He obtained another set of CTIO observations taken in 2003 by astronomer Nathan Smith of the University of Arizona in Tucson, which helped him piece together the whole 20-year outburst.

The images revealed light that seemed to dart through and illuminate a canyon of dust surrounding the doomed star system. "I was jumping up and down when I saw the light echo," said Rest, who has studied light echoes from powerful supernova blasts. "I didn't expect to see Eta Carinae's light echo because the eruption was so much fainter than a supernova explosion. We knew it probably wasn't material moving through space. To see something this close move across space would take decades of observations. We, however, saw the movement over a year's time. That's why we thought it was probably a light echo."

Although the light in the images appears to move over time, it's really an optical illusion. Each flash of light is reaching Earth at a different time, like a person's voice echoing off the walls of a canyon.

The team followed up its study with spectroscopic observations, using the Carnegie Institution of Washington's Magellan and du Pont telescopes at Las Campanas Observatory in Chile. That study helped the astronomers decode the light, revealing the outflow's speed and temperature. The observations showed that ejected material was moving at roughly 445,000 miles an hour (more than 700,000 kilometers an hour), which matches predictions.

Rest's group monitored changes in the intensity of the light echo using the Las Cumbres Observatory Global Telescope Network's Faulkes Telescope South in Siding Spring, Australia. The team then compared those measurements with a plot astronomers in the 1800s made of the light brightening and dimming over the course of the 20-year eruption. The new measurements matched the signature of the 1843 peak in brightness.

The team will continue to follow Eta Carinae because light from the outburst is still streaming to Earth. "We should see brightening again in six months from another increase in light that was seen in 1844," Rest said. "We hope to capture light from the outburst coming from different directions so that we can get a complete picture of the eruption."

Rest's team consists of J.L. Prieto, Carnegie Observatories, Pasadena, Calif.; N.R. Walborn and H.E. Bond, Space Telescope Science Institute, Baltimore, Md.; N. Smith, Steward Observatory, University of Arizona, Tucson; F.B. Bianco and D.A. Howell, Las Cumbres Observatory Global Telescope Network, Goleta, Calif., and University of California, Santa Barbara; R. Chornock, R.J. Foley, and W. Fong, Harvard-Smithsonian Center for Astrophysics, Cambridge, Mass.; D.L. Welch and B. Sinnott, McMaster University, Hamilton, Ontario; M.E. Huber, Johns Hopkins University, Baltimore, Md.; R.C. Smith, Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, La Serena, Chile; I. Toledo, Atacama Large Millimeter Array (ALMA), Chile; D. Minniti, Pontifica Universidad Catolica, Santiago, Chile; and K. Mandel, Harvard-Smithsonian Center for AstroLinkphysics, Cambridge, Mass., and Imperial College London, U.K.

CONTACT

Donna Weaver
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
dweaver@stsci.edu

Armin Rest
Space Telescope Science Institute, Baltimore, Md.
410-338-4358
arest@stsci.edu