Showing posts with label Fornax Cluster. Show all posts
Showing posts with label Fornax Cluster. Show all posts

Tuesday, October 05, 2021

Plunging into the Furnace

Galaxies in the Fornax Cluster




Videos

CosmoView Episode 33: Plunging into the Furnace
CosmoView Episode 33: Plunging into the Furnace 
 
Zoom in to the Fornax Cluster
Zoom in to the Fornax Cluster
 
CosmoView Episodio 33: Tololo captura una galaxia condenada a desaparecer
CosmoView Episodio 33: Tololo captura una galaxia condenada a desaparecer




The Víctor M. Blanco Telescope in Chile captures a doomed galaxy falling into the heart of the Fornax Cluster

The denizens of the Fornax galaxy cluster populate this image from the Víctor M. Blanco 4-meter Telescope, located in Chile at Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF’s NOIRLab. The irregular galaxy lurking in the bottom left corner of this Dark Energy Survey image is NGC 1427A, and its headlong plunge into the heart of the Fornax Cluster over millions of years will eventually result in the galaxy’s disruption.

The Fornax Cluster — which, as the name suggests, lies primarily in the constellation Fornax (the Furnace) — is a relatively nearby galaxy cluster, only about 60 million light-years from Earth. This means that it looms large in the night sky, stretching across an area more than 100 times larger than the full Moon. With over 600 member galaxies, the Fornax Cluster is the second “richest” (most populous) galaxy cluster within 100 million light-years of our galaxy (after the much larger Virgo Cluster).

Two elliptical galaxies dominate the center of this image — visible as the two large patches of diffuse light with bright cores. Such galaxies usually contain much older stars than the more picturesque spiral galaxies, and they tend to be found in galaxy clusters such as the Fornax Cluster. These elliptical galaxies — which are named NGC 1399 and NGC 1404 — are among the brightest members of the Fornax Cluster and are inexorably being drawn together by the force of gravity. This interaction is stripping gas from NGC 1404, the lower elliptical galaxy in this image.

In the bottom left corner of the image appears the irregular galaxy NGC 1427A. This ragged patch of light is a small, irregular collection of stars similar to the Large Magellanic Cloud. Similarly to NGC 1404, NGC 1427A is plunging toward the heart of the cluster at roughly 2.2 million kilometers (or 1.3 million miles) per hour. This headlong rush to destruction will eventually result in the galaxy being disrupted — pulled apart by gravitational interactions with other galaxies.

As with most astronomical observations, this image shows not only the intended target but also a menagerie of objects both close to home and at tremendous distances. The image is dotted with interloping objects from within our own Milky Way — bright stars with diffraction spikes [1]. At the other extreme, distant galaxies provide a colorful backdrop to this image: some are recognizable as spiral galaxies, while others are mere smudges. Despite appearing tiny in this image, each of the distant galaxies contains billions of stars.

This image was captured by the 570-megapixel Dark Energy Camera (DECam), one of the highest-performance, wide-field imagers in the world, as part of the Dark Energy Survey. Funded by the US Department of Energy (DOE) and built and tested at DOE’s Fermilab, DECam was operated by DOE and the National Science Foundation (NSF) between 2013 and 2019. Among its many accomplishments, DECam observations have helped astronomers discover nearly 300 previously unknown dwarf galaxies in the Fornax Cluster.

At present DECam is used for programs covering a huge range of science. Like other survey instruments, DECam captures images of large swaths of the night sky, allowing astronomers to understand structures in the Universe at large scales. Telescope surveys also help identify intriguing astronomical objects worthy of follow-up observation; the most powerful telescopes can only study a minute portion of the night sky at any given time, so astronomers often use surveys to find objects that are interesting enough to observe in detail. 

The analysis of data from the Dark Energy Survey is supported by DOE and the NSF, and the DECam science archive is curated by the Community Science and Data Center (CSDC) at NSF’s NOIRLab.



Notes

[1] Diffraction spikes are formed by light interacting with the inner structure of a telescope, and they can be used to tell something about the telescope that captured an image. Most professional telescopes have a secondary mirror suspended above the main mirror by several thin vanes. These vanes — which together form a structure known as a “spider” — interact with starlight to produce diffraction spikes, with the number of vanes determining the pattern of the resulting spikes.



More Information

NSF’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSF, NRC–Canada, ANID–Chile, MCTIC–Brazil, MINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (in cooperation with DOE’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O'odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.

This work is supported in part by the US Department of Energy Office of Science. The Dark Energy Survey is a collaboration of more than 400 scientists from 26 institutions in seven countries. Funding for the DES Projects has been provided by the US Department of Energy Office of Science, US National Science Foundation, Ministry of Science and Education of Spain, Science and Technology Facilities Council of the United Kingdom, Higher Education Funding Council for England, ETH Zurich for Switzerland, National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, Kavli Institute of Cosmological Physics at the University of Chicago, Center for Cosmology and AstroParticle Physics at Ohio State University, Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Científico e Tecnológico and Ministério da Ciência e Tecnologia, Deutsche Forschungsgemeinschaft, and the collaborating institutions in the Dark Energy Survey.

NCSA at the University of Illinois at Urbana-Champaign provides supercomputing and advanced digital resources for the nation’s science enterprise. At NCSA, University of Illinois faculty, staff, students, and collaborators from around the globe use advanced digital resources to address research grand challenges for the benefit of science and society. NCSA has been advancing one-third of the Fortune 50® for more than 30 years by bringing industry, researchers, and students together to solve grand challenges at rapid speed and scale. 

Fermilab is America’s premier national laboratory for particle physics and accelerator research. A US Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC, a joint partnership between the University of Chicago and the Universities Research Association, Inc. 

The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time.



Links




Contacts:

Vanessa Thomas
Public Information Officer
NSF’s NOIRLab
Tel: +1 520 318 8132

Email:
vanessa.thomas@noirlab.edu

Source: National Optical-Infrared Astronomy Research Laboratory (NFS'sNOIRLab)/News


Wednesday, October 25, 2017

Revealing Galactic Secrets

Revealing the galactic secrets of NGC 1316

The galaxy pair NGC 1316 and 1317 in the constellation of Fornax

PR Image eso1734c
Wide-field view of the sky around the galaxies NGC 1316 and 1317

Annotated view of the sky surrounding NGC 1316



Videos
 
ESOcast 134 Light: Revealing Galactic Secrets (4K UHD)
ESOcast 134 Light: Revealing Galactic Secrets (4K UHD)

Zooming in on the galaxy NGC 1316
Zooming in on the galaxy NGC 1316

Panning across the galaxy NGC 1316
Panning across the galaxy NGC 1316



Countless galaxies vie for attention in this monster image of the Fornax Galaxy Cluster, some appearing only as pinpricks of light while others dominate the foreground. One of these is the lenticular galaxy NGC 1316. The turbulent past of this much-studied galaxy has left it with a delicate structure of loops, arcs and rings that astronomers have now imaged in greater detail than ever before with the VLT Survey Telescope. This astonishingly deep image also reveals a myriad of dim objects along with faint intracluster light.

Captured using the exceptional sky-surveying abilities of the VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile, this deep view reveals the secrets of the luminous members of the Fornax Cluster, one of the richest and closest galaxy clusters to the Milky Way. This 2.3-gigapixel image is one of the largest images ever released by ESO.

Perhaps the most fascinating member of the cluster is NGC 1316, a galaxy that has experienced a dynamic history, being formed by the merger of multiple smaller galaxies. The gravitational distortions of the galaxy’s adventurous past have left their mark on its lenticular structure [1]. Large ripples, loops and arcs embedded in the starry outer envelope were first observed in the 1970s, and they remain an active field of study for contemporary astronomers, who use the latest telescope technology to observe the finer details of NGC 1316’s unusual structure through a combination of imaging and modelling.

The mergers that formed NGC 1316 led to an influx of gas, which fuels an exotic astrophysical object at its centre: a supermassive black hole with a mass roughly 150 million times that of the Sun. As it accretes mass from its surroundings, this cosmic monster produces immensely powerful jets of high-energy particles , that in turn give rise to the characteristic lobes of emission seen at radio wavelengths, making NGC 1316 the fourth-brightest radio source in the sky [2].

NGC 1316 has also been host to four recorded type Ia supernovae, which are vitally important astrophysical events for astronomers. Since type Ia supernovae have a very clearly defined brightness [3], they can be used to measure the distance to the host galaxy; in this case, 60 million light-years. These “standard candles” are much sought-after by astronomers, as they are an excellent tool to reliably measure the distance to remote objects. In fact, they played a key role in the groundbreaking discovery that our Universe is expanding at an accelerating rate.

This image was taken by the VST at ESO’s Paranal Observatory as part of the Fornax Deep Survey, a project to provide a deep, multi-imaging survey of the Fornax Cluster. The team, led by Enrichetta Iodice (INAF – Osservatorio di Capodimonte, Naples, Italy), have previously observed this area with the VST and revealed a faint bridge of light between NGC 1399 and the smaller galaxy NGC 1387 (eso1612) . The VST was specifically designed to conduct large-scale surveys of the sky. With its huge corrected field of view and specially designed 256-megapixel camera, OmegaCAM, the VST can produce deep images of large areas of sky quickly, leaving the much larger telescopes — like ESO’s Very Large Telescope (VLT) — to explore the details of individual objects.



Notes


[1] Lenticular or “lens-shaped” galaxies are an intermediate form between diffuse elliptical galaxies and the better-known spiral galaxies such as the Milky Way.


[2] As this radio source is the brightest in the constellation of Fornax it is also known as Fornax A.


[3] Type Ia Supernovae occur when an accreting white dwarf in a binary star system slowly gains mass from its companion until it reaches a limit that triggers the nuclear fusion of carbon. In a brief period of time, a chain reaction is initiated that eventually ends in a huge release of energy: a supernova explosion. The supernova always occurs at a specific mass, known as the Chandrasekhar limit, and produces an almost identical explosion each time. The similarity of type Ia supernovae allow astronomers to use the cataclysmic events to measure distance.



More Information


This research was presented in the paper “The Fornax Deep Survey with VST. II. Fornax A: A Two-phase Assembly Caught in the Act”, by E. Iodice et al., in the Astrophysical Journal.

The team is composed of E. Iodice (INAF – Astronomical Observatory of Capodimonte, Italy), M. Spavone (Astronomical Observatory of Capodimonte, Italy), M. Capaccioli (University of Naples, Italy), R. F. Peletier (Kapteyn Astronomical Institute, University of Groningen, The Netherlands), T. Richtler (Universidad de Concepción, Chile), M. Hilker (ESO, Garching, Germany), S. Mieske (ESO, Chile), L. Limatola (INAF – Astronomical Observatory of Capodimonte, Italy), A. Grado (INAF – Astronomical Observatory of Capodimonte, Italy), N.R. Napolitano (INAF – Astronomical Observatory of Capodimonte, Italy), M. Cantiello (INAF – Astronomical Observatory of Teramo, Italy), R. D’Abrusco (Smithsonian Astrophysical Observatory/Chandra X-ray Center, US), M. Paolillo (University of Naples, Italy), A. Venhola (University of Oulu, Finland), T. Lisker (Zentrum für Astronomie der Universität Heidelberg, Germany), G. Van de Ven (Max Planck Institute for Astronomy, Germany), J. Falcon-Barroso (Instituto de Astrofísica de Canarias, Spain) and P. Schipani (Astronomical Observatory of Capodimonte, Italy).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile and by 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, 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 Extremely Large Telescope, the ELT, which will become “the world’s biggest eye on the sky”.



Links



Contacts

Enrichetta Iodice
INAF – Osservatorio Astronomico di Capodimonte
Napoli, Italy
Tel: +39 0815575546
Email: iodice@na.astro.it

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

Source: ESO

Wednesday, April 13, 2016

Inside the Fiery Furnace

VST image of the Fornax Galaxy Cluster

PR Image eso1612b
Finding Chart for the Fornax Galaxy Cluster

PR Image eso1612c
The location of the Fornax Galaxy Cluster

PR Image eso1612d
Wide-field view of the Fornax Galaxy Cluster



Videos
 
Zooming in on the Fornax Galaxy cluster
Zooming in on the Fornax Galaxy cluster

VST image of the Fornax Galaxy Cluster
VST image of the Fornax Galaxy Cluster





VLT Survey Telescope Captures the Fornax Cluster


This new image from the VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile captures a spectacular concentration of galaxies known as the Fornax Cluster, which can be found in the southern hemisphere constellation of Fornax (The Furnace). The cluster plays host to a menagerie of galaxies of all shapes and sizes, some of which are hiding secrets.

Galaxies, it seems, are sociable animals and they like to gather together in large groups, known as clusters. Actually it’s gravity that holds the galaxies in the cluster close together as a single entity, with the pull of gravity arising from large amounts of dark matter, as well as from the galaxies we can see. Clusters can contain anything between about 100 and 1000 galaxies and can be between about 5 and 30 million light-years across.

Galaxy clusters do not come in neatly defined shapes so it is difficult to determine exactly where they begin and end. However, astronomers have estimated that the centre of the Fornax Cluster is in the region of 65 million light-years from Earth. What is more accurately known is that it contains nearly sixty large galaxies, and a similar number of smaller dwarf galaxies. Galaxy clusters like this one are commonplace in the Universe and illustrate the powerful influence of gravity over large distances as it draws together the enormous masses of individual galaxies into one region.

At the centre of this particular cluster, in the middle of the three bright fuzzy blobs on the left side of the image, is what is known as a cD galaxy — a galactic cannibal. cD galaxies like this one, called NGC 1399, look similar to elliptical galaxies but are bigger and have extended, faint envelopes [1]. This is because they have grown by swallowing smaller galaxies drawn by gravity towards the centre of the cluster [2].

Indeed, there is evidence that this process is happening before our eyes — if you look closely enough. Recent work by a team of astronomers led by Enrichetta Iodice (INAF – Osservatorio di Capodimonte, Naples, Italy)  [3], using data from ESO’s VST, has revealed a very faint bridge of light between NGC 1399 and the smaller galaxy NGC 1387 to its right. This bridge, which has not been seen before (and is too faint to show up in this picture), is somewhat bluer than either galaxy, indicating that it consists of stars created in gas that was drawn away from NGC 1387 by the gravitational pull of NGC 1399. Despite there being little evidence for ongoing interactions in the Fornax Cluster overall, it seems that NGC 1399 at least is still feeding on its neighbours.

Towards the bottom right of this image is the large barred spiral galaxy NGC 1365. This is a striking example of its type, the prominent bar passing through the central core of the galaxy, and the spiral arms emerging from the ends of the bar. In keeping with the nature of cluster galaxies, there is more to NGC 1365 than meets the eye. It is classified as a Seyfert Galaxy, with a bright active galactic nucleus also containing a supermassive black hole at its centre.

This spectacular image was taken by the VLT Survey Telescope (VST) at ESO’s Paranal Observatory in Chile. At 2.6 metres in diameter, the VST is by no means a large telescope by today’s standards, but it has been designed specifically to conduct large-scale surveys of the sky. What sets it apart is its huge corrected field of view and 256-megapixel camera, called OmegaCAM, which was specially developed for surveying the sky. With this camera the VST can produce deep images of large areas of sky quickly, leaving the really big telescopes — like ESO’s Very Large Telescope (VLT) — to explore the details of individual objects.




Notes

[1] The image captures only the central regions of the Fornax Cluster; it extends over a larger region of sky.

[2] The central galaxy is often the brightest galaxy in a cluster, but in this case the brightest galaxy, NGC 1316, is situated at the edge of the cluster, just outside the area covered by this image. Also known as Fornax A, it is one of the most powerful sources of radio waves in the sky. The radio waves, which can be seen by specialised telescopes sensitive to this kind of radiation, emanate from two enormous lobes extending far into space either side of the visible galaxy. The energy that powers the radio emission comes from a supermassive black hole lurking at the centre of the galaxy which is emitting two opposing jets of high-energy particles. These jets produce the radio waves when they plough into the rarefied gas which occupies the space between galaxies in the cluster.

[3] “The Fornax Deep Survey with VST. I. The extended and diffuse stellar halo of NGC1399 out to 192 kpc” by E. Iodice, M. Capaccioli , A. Grado , L. Limatola, M. Spavone, N.R. Napolitano, M. Paolillo, R. F. Peletier, M. Cantiello, T. Lisker, C. Wittmann, A. Venhola , M. Hilker , R. D’Abrusco, V. Pota, and P. Schipani has been published in the Astrophysical Journal.





More information

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





Links



Contacts

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


 Source: ESO

Tuesday, March 15, 2016

The Distribution of Globular Clusters

An optical image of the Fornax Cluster of galaxies. Astronomers have analyzed the distribution of over eighty thousand globular clusters in the region to infer an active history of galaxy-galaxy interactions. Credit: ESO and the Digitized Sky Survey 2


Globular clusters are gravitationally bound, roughly spherical ensembles of stars. Some contain as many as a million stars, and their sizes are as small as only tens of light-years in diameter. Globular clusters are typically located in the outer regions (the halos) of galaxies, and our Milky Way galaxy has about two hundred of them. Astronomers are interested in globular clusters in part because they are home to many of the oldest known stars, but also because of their locations in the halos.

Collisions between galaxies are commonplace, and the locations of globular clusters can offer evidence of these encounters because they are strongly affected by such interactions. During a collision, a galaxy can grow by absorbing or merging with its neighbor, and some models even predict that clusters form during these interactions. Moreover, it is possible that in a merger large numbers of globular clusters originally belonging to a smaller galaxy may be captured by a larger one. The distribution of globular clusters around a galaxy holds therefore clues to their origins and to the history of the host galaxy. There is an additional benefit: Standard models of cosmology make predictions for how galaxies form and evolve that depend on fundamental properties of the universe like the amounts of dark matter and dark energy. The properties of globular cluster, mostly determined by the accretion histories and mergers of their host galaxies, also reflect the values of these fundamental cosmic quantities.

CfA astronomers Pepi Fabbiano and Raffaele D'Abrusco (now at the University of Naples), together with their colleagues, studied the globular clusters in the core of the Fornax Cluster of galaxies, a complex of over fifty galaxies located about sixty million light-years away. Using optical and near-infrared images taken with the European Southern Observatory's Very Large Survey Telescope, the scientists cataloged over three thousand globular clusters throughout Fornax (about two-thirds of them previously unidentified), providing a rich resource for structural analyses. They find clear evidence for an active history of galaxy-galaxy interactions, for example in bridges between galaxies, elongated groupings, and other unusual arrangements.

While these results by themselves do not refine the values of any cosmological parameters, they are consistent with the standard models, and help complete the evolutionary description of this massive nearby cluster of galaxies.

Reference(s):

"The Extended Spatial Distribution of Globular Clusters in the Core of the Fornax Cluster," R. D'Abrusco, M. Cantiello, M. Paolillo, V. Pota, N.R. Napolitano, L. Limatola, M. Spavone, A. Grado, E. Iodice, M. Capaccioli1, R. Peletier, G. Longo, M. Hilker, S. Mieske, E.K. Grebel, T. Lisker, C. Wittmann, G. van de Ven & G. Fabbiano, ApJ 819, L31, 2016.