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  • richardmitnick 9:56 am on February 11, 2021 Permalink | Reply
    Tags: "Spectacular ‘honeycomb heart’ revealed in iconic stellar explosion", , , , CFHT - Canada France Hawaii Telescope, , , The Crab Supernova Remnant   

    From Royal Astronomical Society (UK): “Spectacular ‘honeycomb heart’ revealed in iconic stellar explosion” 

    From Royal Astronomical Society (UK)

    09/02/2021

    Media contacts

    Dr Morgan Hollis
    Royal Astronomical Society
    Mob: +44 (0)7802 877 700
    press@ras.ac.uk

    Dr Robert Massey
    Royal Astronomical Society
    Mob: +44 (0)7802 877 699
    press@ras.ac.uk

    Science contacts

    Dr Thomas Martin
    Université Laval
    Quebec City (CN)
    thomas.martin.1@ulaval.ca

    Dr Dan Milisavljevic
    Purdue University
    Indiana (US)
    dmilisav@purdue.edu

    Dr Laurent Drissen
    Université Laval
    Quebec City (CN)
    ldrissen@phy.ulaval.ca

    1
    3D reconstruction of the Crab nebula remnant as seen from Earth (right), and from another point of view showing its heart-shaped morphology (left). Credit: Thomas Martin, Danny Milisavljevic and Laurent Drissen. Licence type: Attribution (CC BY 4.0).

    A unique ‘heart-shape’, with wisps of gas filaments showing an intricate honeycomb-like arrangement, has been discovered at the centre of the iconic supernova remnant, the Crab Nebula. Astronomers have mapped the void in unprecedented detail, creating a realistic three-dimensional reconstruction. The new work is published in MNRAS .

    The Crab, formally known as Messier 1, exploded as a dramatic supernova in 1054 CE, and was observed over the subsequent months and years by ancient astronomers across the world. The resulting nebula – the remnant of this enormous explosion – has been studied by amateur and professional astronomers for centuries. However, despite this rich history of investigation, many questions remain about what type of star was originally there and how the original explosion took place.

    Thomas Martin, the researcher at Université Laval (CA) who led the study, hopes to answer these questions using a new 3D reconstruction of the nebula. “Astronomers will now be able to move around and inside the Crab Nebula and study its filaments one by one,” said Martin.

    The team used the powerful SITELLE imaging spectrometer on the Canada-Hawaii-France Telescope (CFHT) in Mauna Kea, Hawaii (US), to compare the 3D shape of the Crab to two other supernova remnants.

    CFHT Sitelle optical imaging Fourier transform spectrometer (IFTS).


    CFHT Telescope, Maunakea, Hawaii, USA, at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level.

    Mauna Kea Observatory, Hawaii USA, altitude 4,213 m (13,822 ft).

    Remarkably, they found that all three remnants had ejecta arranged in large-scale rings, suggesting a history of turbulent mixing and radioactive plumes expanding from a collapsed iron core.

    Co-author Dan Milisavljevic, an assistant professor at Purdue University and supernova expert, concludes that the fascinating morphology of the Crab seems to go against the most popular explanation of the original explosion.

    “The Crab is often understood as being the result of an electron-capture supernova triggered by the collapse of an oxygen-neon-magnesium core, but the observed honeycomb structure may not be consistent with this scenario,” Milisavljevic said.

    The new reconstruction was made possible by the ground-breaking technology used by SITELLE, which incorporates a Michelson interferometer design allowing scientists to obtain over 300,000 high-resolution spectra of every single point of the nebula.

    “SITELLE was designed with objects like the Crab Nebula in mind; but its wide field of view and adaptability make it ideal to study nearby galaxies and even clusters of galaxies at large distances,” said co-author Laurent Drissen.

    Supernova explosions are among the most energetic and influential phenomena in the universe. Consequently, Milisavljevic adds: “It is vital that we understand the fundamental processes in supernovae which make life possible. SITELLE will play a new and exciting role in this understanding.”


    Flythrough of the Crab Nebula
    This 3D reconstruction of the Crab Nebula is made of 406,472 individual points where nebular emission has been detected in SITELLE spectra. The velocity of each element has been translated into a spatial position by assuming an unaccelerated outward motion. The glowing blue sphere at the centre is artificial and simulates the continuum emitted by the pulsar wind nebula. The Milky Way background (Credit: NASA / Goddard Space Flight Center Scientific Visualization Studio) simulates the perspective as observed when moving around the nebula. The soundtrack is a sonification of the data set: using the interferograms directly as a sound wave, multiple samples have been mixed and played at different rates. The sound volume is proportional to the distance to the nebula, and the playing speed simulates the Doppler effect. Credits: Thomas Martin, Danny Milisavljevic and Laurent Drissen.

    SITELLE is the result of a joint collaboration between Université Laval (CN), ABB Inc.-Québec (CN), Université de Montréal (CN) and the CFHT (US), under the scientific leadership of co-author Laurent Drissen.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Royal Astronomical Society (UK), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. The RAS organises scientific meetings, publishes international research and review journals, recognises outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,400 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

    The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

    In 2020 the RAS is 200 years old. The Society is celebrating its bicentennial anniversary with a series of events around the UK, including public lectures, exhibitions, an organ recital, a pop-up planetarium, and the culmination of the RAS 200: Sky & Earth project.

     
  • richardmitnick 3:46 pm on October 14, 2020 Permalink | Reply
    Tags: "New Messier 92 Stellar Stream Discovered", , , , CFHT - Canada France Hawaii Telescope,   

    From Canada France Hawaii Telescope: “New Messier 92 Stellar Stream Discovered” 

    From Canada France Hawaii Telescope, Mauna Kea, Hawaii, USA

    1
    Residual map of the number of stars per pixel along the Messier 92 stream. The residual was obtained by applying the matched-filter technics to the CFIS/PS1 data. The cyan line represents the center of the Messier 92 stellar stream path. Credit: CFIS team.

    A team of astronomers using the Canada-France-Hawaii Telescope discovered a new stellar stream emanating from the Messier 92 globular cluster. This new stream suggests that Messier 92 is actively being disrupted by tidal forces caused by our Milky Way Galaxy. This discovery utilized high quality data obtained as part of the Canada-France-Imaging-Survey (CFIS) using MegaCam at CFHT and from the Pan-STARRS 1 (PS1) survey on Haleakalā, Maui. The discovery of a stellar stream around M92 raises the question of the cluster’s origin and could be used in the future to probe the innermost region of our Galaxy. The team estimates that stellar stream has a mass equivalent to ~10% of the mass of the entire Messier 92 cluster.

    CFHT MegaCam.

    Pann-STARS 1

    Pann-STARS 1 Telescope, U Hawaii, situated at Haleakala Observatories near the summit of Haleakala in Hawaii, USA, altitude 3,052 m (10,013 ft).

    Stellar streams are long thin streams of stars formed as globular clusters or dwarf galaxies are ripped apart by the immense gravity of the Milky Way. The structures formed by these tidal forces are stable over many billions of years. Their longevity allows astronomers to use their presence to better understand the formation of galaxies like the Milky Way as a guide to determine the role of galactic cannibalism in galaxy formation. Additionally, stellar streams are excellent tools to probe the gravitational potential of our Galaxy and study the distribution of dark matter around it.

    “Our simulations of the Messier 92 stellar stream indicated that the stream was likely formed recently, in the last 500 million years,” said Guillaume Thomas, lead author of the paper published in The Astrophysical Journal. “The cluster’s age is around 11 billion years, which indicates that the cluster was not always in its current orbit and makes us wonder where Messier 92 originally orbited.”

    The team identified the 17° long stellar stream from the Messier 92 globular cluster stream using an improved matched-filter method. This method aims to highlight a specific known signal in a noisy dataset and proves to be an extremely efficient tool to detect stellar streams around the Milky Way Galaxy.

    Despite previous observations in this region, the newly discovered Messier 92 stellar stream was hidden by the high number of foreground stars from the Milky Way disk. It was discovered because of the combination of high quality images from both CFIS and Pan-STARRS. The team also used proper motions obtained by the European space mission Gaia to confirm the existence of the stream.

    ESA (EU)/GAIA satellite .

    The Canada-France Imaging Survey is an ongoing large program at CFHT using MegaCam. Allocated 271 nights, CFIS aims to address some of the most fundamental questions in astronomy including the assembly of the Milky Way, properties of dark matter and dark energy, and the growth of structure in the Universe from galaxies to clusters.

    “The discovery of the Messier 92 stellar stream is a testament to the power of the CFIS/PS1 collaboration and the unique capabilities of MegaCam,” says Todd Burdullis, queue observing specialist at the Canada-France-Hawaii Telesope. “The CFIS program is not complete and already the data are enhancing our understanding of the Milky Way. We expect more discoveries like this from the CFIS team in the coming years.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition
    The Canada France Hawaii Telescope Observatory USA hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii, USA. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope

    CFHT

     
  • richardmitnick 11:31 am on September 11, 2020 Permalink | Reply
    Tags: "Galactic Census Reveals Origin of Most "Extreme" Galaxies", , , , CFHT - Canada France Hawaii Telescope, ,   

    From Canada France Hawaii Telescope: “Galactic Census Reveals Origin of Most “Extreme” Galaxies” 

    From Canada France Hawaii Telescope

    9.10.20

    Dr. Eric Peng
    Department of Astronomy
    Kavli Institute for Astronomy and Astrophysics
    Peking University, Beijing, China
    peng@pku.edu.cn

    Dr. Patrick Côté
    Herzberg Astronomy and Astrophysics Research Center
    National Research Council of Canada
    Victoria, BC, Canada
    patrick.cote@nrc-cnrc.gc.ca

    Dr. Chengze Liu
    Department of Astronomy
    School of Physics and Astronomy
    Shanghai Jiao Tong University
    Shanghai, China
    czliu@sjtu.edu.cn

    Dr. Sungsoon Lim
    University of Tampa
    Tampa, FL, USA
    slim@ut.edu

    Media Contact
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    laychak@cfht.hawaii.edu

    1
    A wide field view of the central region of the Virgo Cluster, measuring 4.4 million light years on each side, from the Sloan Digital Sky Survey.

    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude2,788 meters (9,147 ft).

    Some of Virgo’s brightest member galaxies are labeled, including Messier 87, which is located close to the cluster center. Insets show deep images of two structurally extreme galaxies, taken with the MegaCam instrument on CFHT as part of the Next Generation Virgo Cluster Survey.

    CFHT MegaCam.

    An ultra-compact dwarf is within the crosshairs in the lower inset, while an ultra-diffuse galaxy is featured in the upper inset. These galaxies are nearly a thousand times fainter than the bright galaxies visible on this image. Although the compact and diffuse galaxies contain roughly the same number of stars, and their total brightness is similar, they differ in area by a factor of more than 20,000. The scale bars in each inset represent a distance of 10,000 light years.

    Image credits: Sloan Digital Sky Survey, Canada-France-Hawaii Telescope and the NGVS team.

    Virgo Supercluster NASA.

    Astronomers have found that the key to understanding galaxies with “extreme” sizes, either small or large, may lie in their surroundings. In two related studies, an international team found that galaxies that are either “ultra-compact” or “ultra-diffuse” relative to normal galaxies of comparable brightness appear to reside in dense environments, i.e., regions that contain large numbers of galaxies. This has led the team to speculate that these “extreme” objects could have started out resembling normal galaxies, but then evolved to have unusual sizes through interactions with other galaxies.

    The team identified both ultra-compact and ultra-diffuse galaxies as part of an unprecedented census of galaxies residing in the nearby Virgo cluster. The investigation used data from the Next Generation Virgo Cluster Survey (NGVS) obtained at the Canada-France-Hawaii Telescope (CFHT) using MegaCam, a wide-field, optical camera. At a distance of 50 million light years, Virgo is the galaxy cluster nearest to the Milky Way, and contains several thousand member galaxies, the majority of which are revealed, for the first time, in the NGVS data.

    Astronomers discovered ultra-compact dwarf galaxies (UCDs) a quarter century ago, and they are the densest known galaxies in the Universe. Competing theories describe UCDs as either large star clusters, or as the remnants of larger galaxies that have been stripped of their stellar envelopes.

    “We found hundreds of UCDs in the nearby Virgo galaxy cluster, and at least some of them appear to have started their lives as larger galaxies,” said Dr. Chengze Liu of Shanghai Jiao Tong University, lead author of the first study.

    While UCDs are similar in appearance to a large star cluster, a number of UCDs in this study were found with faint stellar envelopes surrounding the central, compact core. These envelopes could be the last remnants of a galaxy that has gradually been stripped away by gravitational tidal forces from neighboring galaxies. Additionally, UCDs were found to inhabit preferentially the regions of the Virgo cluster with the highest galaxy densities. Together, these pieces of evidence point to an environmentally-induced transformation as being responsible for producing some UCDs.

    Ultra-diffuse galaxies (UDGs) are a mystery at the other end of the size spectrum. They are much larger, and more diffuse, than typical galaxies with similar brightness. Some theories suggest that UDGs are massive galaxies whose gas — the fuel for their star formation — was removed before many stars could form. Others suggest that they were once normal galaxies that have been made more diffuse through mergers and interactions.

    “We found that the ultra-diffuse galaxies in the Virgo cluster are more concentrated toward the dense cluster core, indicating that a dense environment may be important for their formation,” said Dr. Sungsoon Lim of the University of Tampa, and the lead author of the second study. “The diversity in their properties indicate that while no single process has given rise to all objects within the UDG class, at least some UDGs have appearances suggesting their diffuse nature is due to tidal interactions or to the merger of low-mass galaxies.”

    Another mystery is that some ultra-diffuse galaxies were found to contain significant populations of globular star clusters. “The intense star-forming events needed to make globular clusters generally make a galaxy less, rather than more diffuse, so understanding how we get globular clusters in ultra-diffuse galaxies is an interesting challenge,” said Prof. Eric Peng of Peking University’s Kavli Institute for Astronomy and Astrophysics, and co-author on both studies.

    “To find galaxies that are truly unusual, you first need to understand the properties of so-called normal galaxies,” said Dr. Patrick Côté of the National Research Council of Canada’s Herzberg Astronomy and Astrophysics Research Center, and an author on both studies. “NGVS provides the deepest, most complete look at the entirety of the Virgo cluster galaxy population, allowing us to find the most compact and most diffuse galaxies, advancing our understanding of how they fit into the general picture of galaxy formation.”

    These research results have been presented in two papers that were published recently in the Astrophysical Journal ( Lim et al. 2020 [The Astrophysical Journal]; Liu et al. 2020 [The Astrophysical Journal]).

    NGVS is based on observations obtained with MegaPrime/MegaCam, a joint project of the Canada-France-Hawaii Telescope and CEA/DAPNIA, and on data produced and hosted at the Canadian Astronomy Data Centre. CFHT is operated by the National Research Council of Canada, the Institute National des Sciences de l’Universe of the Centre National de la Recherche Scientifique of France, and the University of Hawai’i.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition
    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope

    CFHT

     
  • richardmitnick 10:24 am on September 5, 2020 Permalink | Reply
    Tags: "New Machine Learning Applications for SITELLE", , , , CFHT - Canada France Hawaii Telescope, CFHT Sitelle optical imaging Fourier transform spectrometer.,   

    From Canada France Hawaii Telescope: “New Machine Learning Applications for SITELLE” 


    From Canada France Hawaii Telescope

    8.26.20
    Carter Rhea
    L’Université de Montréal
    carter.rhea@umontreal.ca

    Media Contact
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    laychak@cfht.hawaii.edu

    Machine learning, a new technology revolutionizing the analysis of large data sets, has gained traction in the astronomical community for the past decade. A team of researchers led by Carter Rhea from the Université de Montréal and Laurie Rousseau-Nepton of the Canada-France-Hawaii Telescope are spearheading efforts to bring machine learning into the flow of SITELLE data analysis. In the first paper of the series [The Astrophysical Journal], the team shares their application of a convolutional neural network to SITELLE spectra to estimate kinematic parameters.

    CFHT Sitelle optical imaging Fourier transform spectrometer (IFTS).

    1
    Residual map of the recovered velocity parameter in the Southwest field of Messier 33. The residual was calculated by taking the difference between the network’s estimate and that of the ORCS fitting software.

    SITELLE, the CFHT’s unique imaging Fourier Transform Spectrograph, is capable of generating 3D data cubes containing more than 4 million spatial pixels and a spectral resolving power of 10,000 resulting in a total of over 40 billion spectral pixels or spaxels. Analysis on this volume of data requires a dedicated suite of tools designed specifically for SITELLE by Thomas Martin, astronomer at the Université Laval. The ORCS (Outils de Réduction de Cubes Spectraux) software package was designed precisely for this reason; using ORCS, an astronomer can fit each spectrum in the data cube. SITELLE measures the amount of light, or photons, that hits each pixel during the exposure. ORCS “fits” those photon counts into a scientifically usable spectrum, enabling astronomers to learn about the complex physics in planetary nebulae and HII regions.

    Before fitting a spectrum, ORCS requires the user to input an initial estimate for the velocity and broadening parameters. Astronomers rely on previous studies of their objects to determine these initial estimates. However, these estimates frequently come from older, potentially outdated, research which may not be appropriate or available for all nebulae. An inaccurate initial estimate triggers a series of unsound calculations ultimately leading to an incorrect solution. Prior to the team’s works, SITELLE users did not have a standard method for determining initial estimate values.

    “When we started this project, we were hoping to capitalize on recent successes employing a machine learning technique known as a convolutional neural network to calculate spectral parameters,” says Simon Prunet, CFHT resident astronomer. “Convolutional neural networks are becoming increasingly common in the field of image processing including recent success in astronomy.”

    These networks take spectrum and break them down into their most important components, learning to extract key parameters from the input. Convolutional neural networks are trained with labeled data through a process known as supervised learning where the networks learn to associate patterns in the input images with corresponding output parameters. The networks are trained on pre-labeled data until they properly categorize inputs based on their labels. In the case of SITELLE , the team trained their algorithm on a suite of synthetic spectra specifically tailored to mimic actual data from the instrument. The synthetic data were generated using preexisting tools in another custom designed SITELLE software package, ORBS (Outils de Réduction Binoculaire pour SITELLE). After training the algorithm, it was extensively tested on freshly generated synthetic spectrum. Once the algorithm demonstrated its capability of accurately estimating the velocity and broadening parameters of emission-lines in SITELLE spectra, the team progressed their testing to include real observations taken by SITELLE. The network was applied to a SITELLE field from the galaxy Messier 33. The team selected Messier 33, a spiral galaxy hosting an assortment of emission-line nebulae, supernovae remnants, and planetary nebulae, due to Messier 33’s well established velocity and line broadening input estimates. The results indicate that the network recovers the broadening and velocity values with errors similar to those found by ORCS.

    “This type of analysis is a game-changer for astronomers using SITELLE,” says Laurie Rousseau-Nepton, CFHT resident astronomer and SITELLE instrument scientist. “The network analyzes the data in a fraction of the time previously required, greatly speeding up the time it takes to reduce the enormous amounts of data generated by projects like our large program SIGNALS.”

    Carter Rhea, the machine learning project’s lead and graduate student at Université de Montréal , notes that “This is the beginning of what we can do with machine learning to revolutionize data analysis from instruments such as SITELLE. It is incredibly exciting for me to work on the intersection of machine learning and astronomical data sets.”

    The team’s paper is the first in a series of papers on machine learning applications towards SITELLE data .

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition
    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope

    CFHT

     
  • richardmitnick 3:37 pm on January 2, 2020 Permalink | Reply
    Tags: "GMRT discovers a gigantic ring of hydrogen gas around a distant galaxy", A mysterious ring of hydrogen gas around a distant galaxy, , , , CFHT - Canada France Hawaii Telescope, , , National Centre for Radio Astrophysics (NCRA) in Pune India, , The galaxy AGC 203001 about 260 million light-years away from us.   

    From phys.org: “GMRT discovers a gigantic ring of hydrogen gas around a distant galaxy” 


    From phys.org

    January 2, 2020
    Tata Institute of Fundamental Research

    1
    The optical image from the CFHT telescope with the distribution of neutral hydrogen in the form of a large ring shown in red as observed by the GMRT. The other two red blobs show the distribution of neutral hydrogen around two other galaxies which are in the vicinity of the ring. Credit: O. Bait (NCRA-TIFR/GMRT), Duc (ObAS/CFHT)


    CFHT Telescope, Maunakea, Hawaii, USA, at Maunakea, Hawaii, USA,4,207 m (13,802 ft) above sea level

    A team of astronomers at the National Centre for Radio Astrophysics (NCRA) in Pune, India have discovered a mysterious ring of hydrogen gas around a distant galaxy, using the Giant Metrewave Radio Telescope (GMRT).

    Giant Metrewave Radio Telescope, an array of thirty telecopes, located near Pune in India

    The ring is much bigger than the galaxy it surrounds and has a diameter of about 380,000 light-years (about 4 times that of our Milky Way).

    The galaxy (named AGC 203001), is located about 260 million light-years away from us. There is only one other such known system with such a large neutral hydrogen ring. The origin and formation of such rings is still a matter of debate among astrophysicists.

    Neutral hydrogen emits radio waves at a wavelength of about 21cm. This radiation from neutral hydrogen atoms has allowed radio astronomers to map the amount and distribution of neutral hydrogen gas in our Milky Way galaxy and in other galaxies in the Universe. Typically, large reservoirs of neutral hydrogen gas are found in galaxies which are actively forming new stars. However, despite showing no signs of active star formation the galaxy AGC 203001 was known to have large amounts of hydrogen, although its exact distribution was not known. The unusual nature of this galaxy motivated astronomers in NCRA to use the GMRT to conduct high-resolution radio observation of this galaxy to find out where in the galaxy this gas lies.

    The GMRT observations revealed that the neutral hydrogen is distributed in the form of a large off-centered ring extending much beyond the optical extent of this galaxy. More puzzlingly, the astronomers found that the existing optical images of the ring showed no sign of it containing stars. In collaboration with two French astronomers, Pierre-Alain Duc and Jean-Charles Cuillandre, the NCRA team obtained a very sensitive optical image of this system using the Canada-France-Hawaii-Telescope (CFHT) in Hawaii, USA. However, even these images do not show any sign of starlight associated with the hydrogen ring.

    There is no clear answer today as to what could lead to the formation of such large, starless rings of hydrogen. Conventionally, galaxy-galaxy collisions were thought to lead to the formation of such off-centered rings around galaxies. However, such rings also generally contain stars. This is contrary to what is found in this ring. Figuring out how this ring was formed remains a challenge to astronomers.

    Encouraged by this discovery, the team is now conducting a large survey to map the neutral hydrogen around several more similar galaxies. If some of them also show rings like this, it should help us to better understand the formation mechanism behind such rare rings.

    This work was led by Omkar Bait, a doctoral student at NCRA working under the supervision of Yogesh Wadadekar. This work forms a part of Omkar’s doctoral thesis. Sushma Kurapati, who is another doctoral student at NCRA also played a role in the radio observations. Other expert scientists who contributed include, Pierre-Alain Duc (Universite de Strasbourg, Strasbourg, France), Jean-Charles Cuillandre (PSL University, Paris, France), Peter Kamphuis (Ruhr University, Bochum, Germany) and Sudhanshu Barway (Indian Institute of Astrophysics, Bengaluru, India).

    Science paper:
    Discovery of a large Hi ring around the quiescent galaxy AGC 203001
    [MNRAS]

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    About Phys.org in 100 Words

    Phys.org™ is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 1:48 pm on August 27, 2019 Permalink | Reply
    Tags: , , , CFHT - Canada France Hawaii Telescope, , Haumea was named after the Hawaiian goddess of childbirth- an homage to Maunakea where Haumea's moons were discovered., , the Haumea family named after the dwarf planet of the same name.   

    From Canada France Hawaii Telescope: “A Search for Distant Collisional Remnants” 

    CFHT icon
    From Canada France Hawaii Telescope

    8.26.19

    Media Contact:
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    808-885-3121
    laychak@cfht.hawaii.edu

    Science Contact
    Rosemary Pike
    ASIAA
    repike@asiaa.sinica.edu.tw

    1
    The summit of Maunakea includes many telescopes, including the Canada-France-Hawaii Telescope (CFHT, center, white) and Gemini Observatory (closest, silver). These distant icy objects were discovered in the Outer Solar System Origins Survey (OSSOS) on CFHT. Half of the OSSOS survey fields are visible in the photo, and they are marked with white rectangles.

    The distant Solar System contains a large reservoir of objects beyond the orbit of Neptune, which are the icy remnants of planetary formation. These small icy bodies are challenging to discover, but their orbital properties and surface composition provide critical information about the formation and evolution of the Solar System. The Outer Solar System Origins Survey (OSSOS) and its companion surveys
    (CFEPS, HiLat, Alexandersen) covered 1,209 square degrees and discovered more than 1,000 trans-Neptunian objects (TNOs). The main surveys were conducted using the Canada-France-Hawaii Telescope on Maunakea.

    Hidden among this large number of discoveries are three objects which may belong to the Haumea family. Named after the dwarf planet of the same name, the Haumea family of objects are thought to have formed as the result of a collision several billion years ago. Called a collision family by astronomers, the family members are identified by their similar orbital elements and surfaces which display water-ice. The namesake object, Haumea, was named after the Hawaiian goddess of childbirth, an homage to Maunakea where Haumea’s moons were discovered.

    While the asteroid belt contains more than 100 collisional families, only one family has been identified in the Kuiper belt. The Kupier Belt is a region of our Solar System located 30-50 times more distant than the Earth from the sun. Understanding the collision which created the Haumea family provides critical information about the types of collisions which have occurred in the Kuiper belt, and potential insight into how to best search for additional families of objects past Neptune.

    A recent paper in Nature Astronomy written by Rosemary Pike from ASIAA and the OSSOS team shows surprising results for the Haumea family. The OSSOS team discovered three potential Haumea family members significantly brighter than the survey limits.

    “Based on our discovery of these three large objects, we expected to find 10-30 smaller Haumea family TNOs” said Rosemary Pike, lead author of the Nature Astronomy paper. “We didn’t find the smaller objects which gives us important clues about the formation of the Haumea family”

    2
    Haumea and its family members (red/pink) have orbits that are different from the majority of classical TNOs (gray). The Haumea family members have higher inclinations, so their orbits extend further from the ecliptic plane where the classical TNOs cluster.

    Pike and the team carefully tested the survey sensitivity and models of the orbital distribution of the Haumea family, and determined conclusively that the Haumea family has significantly less small objects than the other TNO populations. They describe this result as a shallow size distribution in their model. The OSSOS survey has well understood discovery bias, so the team conducted the first statistically rigorous testing of the Haumea family size distribution, which provides the first robust constraints on how many small and large Haumea family members exist in the Kuiper belt.

    Pike and the OSSOS team determined that the shallow size distribution of the Haumea family members is different from the size distribution of all other TNOs, important implications for the formation of this family. A shallow size distribution like the one seen with the Haumea family is produced by graze and merge simulations, where the impacting object grazed the proto-Haumea, slowed, and returned to collide again and merge with Haumea. The newly merged objects rotate quickly and shed material forming the other family members. However, the orbital distribution expected by a graze and merge collision does not match the known orbital distribution of Haumea family members. Rather the Haumea family has an isotropic orbital distribution. An isotropic orbital distribution results from a catastrophic collision, where the impactor is immediately destroyed. Catastrophic collisions produce a steep size distribution conflicting with the team’s results. This conflict inspires future work on the Haumea family, which will focus on understanding possible formation scenarios which reproduce both the observed orbital and size distributions.

    “The OSSOS team’s long history of observations with Megcam here at CFHT and coordinated observations with Gemini Observatory means they really understand how their discovery of these three reflects the number of Haumea members in Kuiper Belt,” says Todd Burdullis, QSO operations specialsts at CFHT. “Their discovery about the formation of the Haumea family add to the long string of great discoveries about the outer Solar System from CFHT”.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition
    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope

    CFHT

     
  • richardmitnick 8:37 am on April 24, 2019 Permalink | Reply
    Tags: "Omega Centauri’s lost stars", , , “Fimbulthul” contains 309 stars stretching over 18° in the sky, , CFHT - Canada France Hawaii Telescope, , We now know that Omega Centauri is the most massive globular cluster in the Milky Way   

    From Canada France Hawaii Telescope: “Omega Centauri’s lost stars” 

    CFHT icon
    From Canada France Hawaii Telescope

    4.22.19

    Mary Beth Laychak, Outreach manager
    Canada-France-Hawaii Telescope
    laychak@cfht.hawaii.edu

    1
    The Milky Way, as seen by the Gaia satellite. Streams of co-moving stars are shown colored according to their motions as measured by Gaia. The “Fimbulthul” stream which is due to stars lost from the omega Centauri globular cluster (white box) has been highlighted. Credit R. Ibata.

    A team of researchers from the Strasbourg Astronomical Observatory, Bologna Observatory and the University of Stockholm has identified a stream of stars that was torn off the globular cluster Omega Centauri. Searching through the 1.7 billion stars observed by the ESA Gaia mission, they have identified 309 stars that suggest that this globular cluster may actually be the remnant of a dwarf galaxy that is being torn apart by the gravitational forces of our Galaxy.

    ESA/GAIA satellite

    In 1677, Edmond Halley gave the name “Omega Centauri” (ω Cen) to what he thought was a star in the Centaurus constellation. Later in 1830 John Herschel realized that it was in fact a globular cluster that could be resolved into individual stars. We now know that Omega Centauri is the most massive globular cluster in the Milky Way: it is about 18,000 light years from us and contains several million stars that are about 12 billion years old. The nature of this object has been the subject of much debate: is it really a globular cluster, or could it be the heart of a dwarf galaxy whose periphery has been dispersed by the Milky Way?

    This last hypothesis is based on the fact that ω Cen contains several stellar populations, with a large range of metallicities (i.e. heavy element content) that betray a formation over an extended period of time. An additional argument in favor of this hypothesis would be to find debris from the cluster scattered along its orbit in the Milky Way. Indeed, when a dwarf galaxy interacts with a massive galaxy like our own, stars are torn off by gravitational tidal forces, and these stars remain visible for a time as stellar streams, before becoming dispersed in the vast volumes of interstellar space surrounding the massive galaxy.

    By analyzing the motions of stars measured by the Gaia satellite with an algorithm called STREAMFINDER developed by the team, the researchers identified several star streams. One of them, named “Fimbulthul” (after one of the rivers in Norse mythology that existed at the beginning of the world), contains 309 stars stretching over 18° in the sky.

    By modeling the trajectories of the stars, the team showed that the Fimbulthul structure is a stellar tidal stream torn off ω Cen, extending up to 28° from the cluster. Spectroscopic observations of 5 stars of this stream with the Canada-France Hawaii Telescope show that their velocities are very similar, and that they have metallicities comparable to the stars of ω Cen itself, which reinforces the idea that the tidal stream is linked to ω Cen.

    “The stars that the team observed were quite faint for the instrument we were using,” says Dr. Nadine Manset, instrument scientist for Espadons and CFHT’s astronomy group manager. “It is great to see such challenging observations reinforce the Fimbulthul structure’s link to ω Cen.”

    The researchers were then able to show that the stream is also present in the very crowded area of sky in the immediate vicinity of the cluster. Further modeling of the tidal stream will constrain the dynamical history of the dwarf galaxy that was the progenitor of ω Cen, and allow us to find even more stars lost by this system into the halo of the Milky Way.

    The team’s paper appeared in the April 22nd edition of Nature.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition
    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope

    CFHT

     
  • richardmitnick 10:27 am on April 6, 2019 Permalink | Reply
    Tags: "VESTIGE Traces Ionized Gases of Messier 87", , , , CFHT - Canada France Hawaii Telescope, , Messier 87 - NGC 4486, Messier 87 hosts the powerful radio source Virgo A, Virgo Cluster   

    From Canada France Hawaii Telescope: “VESTIGE Traces Ionized Gases of Messier 87” 

    CFHT icon
    From Canada France Hawaii Telescope

    April 04 2019

    Media contact:
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    laychak@cfht.hawaii.edu

    Science Contact:
    Alessandro Boselli
    Laboratorie d’Astrophsique de Marseille
    alessandro.boselli@lam.fr

    The VESTIGE team, lead by Alessandro Boselli, from the Laboratoire d’Astrophysique de Marseille, using MegaCam at the Canada-France-Hawaii Telescope has recently released an extremely deep image in the narrow-band Halpha filter of the elliptical galaxy Messier 87. Located at the heart of the Virgo Cluster, Messier 87 is one of the most studied galaxies in the Universe. The image, used on the cover of this month’s Astronomy & Astrophysics journal, reveals the presence of spectacular filaments of ionised gas extending several kilo parsecs from the galaxy. These filaments illustrate an ongoing interaction between Messier 87 and the surrounding environment.

    CFHT MegaCam

    1
    The pseudo-colour image of M87 obtained by combining Chandra 1.0-3.5 keV (blue), VESTIGE Halpha+[NII] (green), and the VLA radio continuum at 90 cm (red) frames of the galaxy. Image credit: VESTIGE team

    NASA/Chandra X-ray Telescope

    NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

    Messier 87 is the dominant elliptical galaxy in the Virgo cluster, the closest and richest cluster of galaxies located at 50 million light-years from Earth.

    Virgo Supercluster NASA

    The galaxy is located in the deep of the cluster potential well, and it is surrounded by hot and dense gas visible in the X-ray. Messier 87 hosts the powerful radio source Virgo A, whose presence can be detected by an extended radio jet visible at multiple wavelengths across the electromagnetic spectrum.

    2
    Messier 87 (M87), also known as Virgo A or the Smoking Gun, is a supergiant elliptical galaxy located in the core of the Virgo Cluster, in the southern constellation Virgo.

    The galaxy has an apparent magnitude of 9.59 and lies at a distance of 53.5 million light years from Earth. It has the designation NGC 4486 in the New General Catalogue.

    Virgo A occupies an area of 7.2 by 6.8 arc minutes of apparent sky, which corresponds to a linear diameter of 120,000 light years, roughly the same size as the Milky Way. It is the second brightest galaxy in the northern part of the Virgo Cluster, second only to Messier 49.

    The radio jet interacts with the surrounding diffuse hot gas, producing giant bubbles that disturb the superheated plasma or intracluster medium lying between the galaxies of the Virgo Cluster.

    [top left] – This radio image of the galaxy Messier 87, taken with the Very Large Array (VLA) radio telescope [above] in February 1989, shows giant bubble-like structures where radio emission is thought to be powered by the jets of subatomic particles coming from the galaxy’s central black hole. The false color corresponds to the intensity of the radio energy being emitted by the jet. Messier 87 is located 50 million light-years away in the constellation Virgo.
    [top right] – A visible light image of the giant elliptical galaxy Messier 87, taken with NASA Hubble Space Telescope’s Wide Field Planetary Camera 2 in February 1998, reveals a brilliant jet of high-speed electrons emitted from the nucleus (diagonal line across image). The jet is produced by a 3-billion-solar-mass black hole.

    NASA/ESA Hubble Telescope


    NASA/Hubble WFPC2. No longer in service.


    [bottom] – A Very Long Baseline Array (VLBA) radio image of the region close to the black hole, where an extragalactic jet is formed into a narrow beam by magnetic fields.

    NRAO/VLBA


    The false color corresponds to the intensity of the radio energy being emitted by the jet. The red region is about 1/10 light-year across. The image was taken in March 1999.
    Credit: NASA, National Radio Astronomy Observatory/National Science Foundation, John Biretta (STScI/JHU), and Associated Universities, Inc.

    “The very nature of these radio monsters, typical in the core of massive clusters, is still quite unclear”, says Alessandro Boselli, the VESTIGE primary investigator and lead author on the A&A paper. “They play a crucial role in galaxy evolution within high-density regions.”

    VESTIGE or A Virgo Environmental Survey Tracing Ionized Gas Emission, one of the large surveys currently being observed using CFHT, observes the Virgo Cluster in part to learn more about the role of radio monsters. With fifty nights of telescope time at CFHT over the course of two years, VESTIGE aims to understand the role of environment on galaxy evolution. As a follow-up of the Next Generation Virgo Survey (NGVS) which covered the area through broad filters (ugiz) with MegaCam, the VESTIGE team uses a narrow band Halpha filter on that same instrument to conduct a deep imaging survey of the area observed by the NGVS. These extremely deep images revealed the presence of spectacular filaments and plumes of ionised gas crossing the galaxy from the south-east to the north-west. Follow up spectroscopy taken with MUSE at the VLT (ESO) suggests that the gas is shock ionised.

    ESO MUSE on the VLT on Yepun (UT4)


    ESO VLT at Cerro Paranal in the Atacama Desert, •ANTU (UT1; The Sun ),
    •KUEYEN (UT2; The Moon ),
    •MELIPAL (UT3; The Southern Cross ), and
    •YEPUN (UT4; Venus – as evening star).
    elevation 2,635 m (8,645 ft) from above Credit J.L. Dauvergne & G. Hüdepohl atacama photo,

    The geometry of the gas filament and its position in relation to the radio jet and the hot gas previously observed in X-rays suggest that the gas is ionised by the expanding bubbles. Local instabilities in the intracluser medium cause the gas to cool along magnetically supported filaments into the central elliptical. These filmants may also be the remnant of the cold gas disc of a star-forming galaxy recently accreted by M87 through galactic cannibalism. As the gas falls into galaxy, it may feed the AGN in the centre of Messier 87 and thus be at the origin of the strong radio activity of this intriguing object.

    The exceptional sensitivity and angular resolution of MegaCam coupled with narrow-band filters allows the VESTIGE team to detection of extended ionised gas low-surface brightness features associated to galaxies in high-density region and are thus a key instrument to witness an ongoing perturbation. “The observing technique used by the VESTIGE team is crucial for the study of the role of the environment on galaxy evolution,” says Todd Burdullis, queue observation specialist at CFHT. “The VESTIGE team’s research using Megacam is really probing one of the main questions in extragalactic astronomy.”

    The results of this research, as those of other works conducted by the VESTIGE team on this topic have been presented in a paper recently published in A&A.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope

    CFHT

     
  • richardmitnick 9:17 am on February 15, 2019 Permalink | Reply
    Tags: , , , CFHT - Canada France Hawaii Telescope, , Quest for new worlds beyond our Solar System in the form of planetary systems of nearby red dwarfs like the one discovered around Trappist-1 or infant stars and their planet-forming accretion discs th, SPIRou (SpectroPolarimètre InfraRouge) spectropolarimeter   

    From Canada France Hawaii Telescope: “2019 January: Green light for SPIRou science at CFHT” 

    CFHT icon
    From Canada France Hawaii Telescope

    CFHT SPIRou Project at CFHT

    CFHT The Cryo-Cooled Adventures of SPIRou

    SPIRou passed the final acceptance review

    Almost exactly one year after reaching its new home atop Maunakea on the big island of Hawaii, and following one complete year of intense in-lab and on-sky testing at CFHT, SPIRou passed the final acceptance review on 2019 January 24, and is now ready to initiate its exciting scientific exploration.

    During this testing period, the performance of SPIRou was scrutinized by the project team on all aspects that matter for science observations (mainly wavelength domain, resolving power, spectral response, radial velocity precision and polarimetric capabilities) then compared to expectations to demonstrate that the instrument is mostly compliant with original specifications and ready to tackle the ambitious science programmes for which it was designed.

    Acceptance tests demonstrated that SPIRou behaves nominally, apart from a lower throughput in the bluest spectral region (YJ photometric band, spanning 1-1.4 µm) and a brighter thermal background in the reddest spectral region (coming from the warm components of the instrument whose thermal emission becomes strong at 2.3 µm and beyond, compared to the flux of the dim stars that SPIRou will observe).

    As a spectropolarimeter, SPIRou is also found to perform as expected; its velocimetric precision is estimated to be at least 2 m/s rms, with data reduction and the correction of telluric lines from the Earth atmosphere currently being the main limiting factor (more about this in a forthcoming news).

    SPIRou performances were outlined on 2019 January 23 by the project team for the final acceptance review panel, gathering Magali Deleuil (AMU/LAM), Pierre Kern (CNRS/INSU, panel chair), Gaspare LoCurto (ESO), Guy Perrin (CNRS/INSU), John Rayner (UH), Andy Sheinis (CFHT), Doug Simons (CFHT CEO, panel co-chair) and Michael Toplis (OMP). Following a discussion session on the following day, the panel members gave SPIRou a green light to begin its quest for new worlds beyond our Solar System, in the form of planetary systems of nearby red dwarfs like the one discovered around Trappist-1, or infant stars and their planet-forming accretion discs that are still evolving towards maturity.

    With 50 nights already scheduled in semester 2019a and 300 nights allocated over the next 4 years for a large programme (called the SPIRou Legacy Survey) on SPIRou main science goals, SPIRou is already the main bright-time instrument at CFHT and is expected to rapidly ramp up in the forthcoming semesters.

    The SPIRou project and science teams warmly thank the CFHT staff for its key participation in the successful implementation of SPIRou on the telescope, and the final acceptance review panel members for their time and insightful opinion on how to further improve the performance of SPIRou.

    1
    Illustrated summary of SPIRou activities in 2018 at CFHT (©SPIRou team)

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.
    stem
    Stem Education Coalition

    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope
    CFHT Interior

     
  • richardmitnick 12:15 pm on October 9, 2018 Permalink | Reply
    Tags: 2MASS 0249 c and beta Pictoris b, 2MASS 0249 system, Astronomers Find a Famous Exoplanet's Doppelgänger, , , , CFHT - Canada France Hawaii Telescope, , Finding two exoplanets with almost identical appearances and yet having formed so differently opens a new window for understanding these objects   

    From Canada France Hawaii Telescope: “Astronomers Find a Famous Exoplanet’s Doppelgänger” 

    CFHT icon
    From Canada France Hawaii Telescope

    1
    Direct Wircam image of 2MASS 0249 system taken wiht CFHT’s infrared camera WIRCam. 2MASS 0249c is located 2000 astronomical units from the host brown dwarfs that are unresolved in this image. Credits: T. Dupuy, M. Liu

    When it comes to extrasolar planets, appearances can be deceiving. Astronomers have imaged a new planet, and it appears nearly identical to one of the best studied gas-giant planets. But this doppelgänger differs in one very important way: its origin.

    “We have found a gas-giant planet that is a virtual twin of a previously known planet, but it looks like the two objects formed in different ways,” said Trent Dupuy, astronomer at the Gemini Observatory and leader of the study.

    Emerging from stellar nurseries of gas and dust, stars are born like kittens in a litter, in bunches and inevitably wandering away from their birthplace. These litters comprise stars that vary greatly, ranging from tiny runts incapable of generating their own energy (called brown dwarfs) to massive stars that end their lives with supernova explosions. In the midst of this turmoil, planets form around these new stars. And once the stellar nursery exhausts its gas, the stars (with their planets) leave their birthplace and freely wander the Galaxy. Because of this exodus, astronomers believe there should be planets born at the same time from the same stellar nursery, but orbiting stars that have moved far away from each other over the eons, like long-lost siblings.

    “To date, exoplanets found by direct imaging have basically been individuals, each distinct from the other in their appearance and age. Finding two exoplanets with almost identical appearances and yet having formed so differently opens a new window for understanding these objects,” said Michael Liu, astronomer at the University of Hawai`i Institute for Astronomy, and a collaborator on this work.

    Dupuy, Liu, and their collaborators have identified the first case of such a planetary doppelgänger. One object has long been known: the 13-Jupiter-mass planet beta Pictoris b, one of the first planets discovered by direct imaging, back in 2009. The new object, dubbed 2MASS 0249 c, has the same mass, brightness, and spectrum as beta Pictoris b.

    After discovering this object with the Canada-France-Hawaii Telescope (CFHT), Dupuy and collaborators then determined that 2MASS 0249 c and beta Pictoris b were born in the same stellar nursery. On the surface, this makes the two objects not just look-alikes but genuine siblings.

    However, the planets have vastly different living situations, namely the types of stars they orbit. The host for beta Pictoris b is a star 10 times brighter than the Sun, while 2MASS 0249 c orbits a pair of brown dwarfs that are 2000 times fainter than the Sun. Furthermore, beta Pictoris b is relatively close to its host, about 9 astronomical units (AU, the distance from the Earth to the Sun), while 2MASS 0249 c is 2000 AU from its binary host.

    These drastically different arrangements suggest that the planets’ upbringings were not at all alike. The traditional picture of gas-giant formation, where planets start as small rocky cores around their host star and grow by accumulating gas from the star’s disk, likely created beta Pictoris b. In contrast, the host of 2MASS 0249 c did not have enough of a disk to make a gas giant, so the planet likely formed by directly accumulating gas from the original stellar nursery.

    “2MASS 0249 c and beta Pictoris b show us that nature has more than one way to make very similar looking exoplanets,” says Kaitlin Kratter, astronomer at the University of Arizona and a collaborator on this work. “beta Pictoris b probably formed like we think most gas giants do, starting from tiny dust grains. In contrast, 2MASS 0249 c looks like an underweight brown dwarf that formed from the collapse of a gas cloud. They’re both considered exoplanets, but 2MASS 0249 c illustrates that such a simple classification can obscure a complicated reality.”

    2
    The infrared spectra of 2MASS 0249c and beta Pictoris b are similar, as expected for two objects of comparable mass that formed in the same stellar nursery. Unlike 2MASS 0249c, beta Pictoris b orbits much closer to its massive host star and is imbedded in a bright circumstellar disk. Credits: T. Dupuy, ESO/A.-M. Lagrange et al.

    The team first identified 2MASS 0249 c using images from CFHT, and their repeated observations revealed this object is orbiting at a large distance from its host. The system belongs to the beta Pictoris moving group, a widely dispersed set of stars named for its famous planet-hosting star. The team’s observations with the W. M. Keck Telescope determined that the host is actually a closely separated pair of brown dwarfs.

    So altogether, the 2MASS 0249 system comprises two brown dwarfs and one gas-giant planet. Follow-up spectroscopy of 2MASS 0249 c with the NASA Infrared Telescope Facility and the Astrophysical Research Consortium 3.5-meter Telescope at Apache Point Telescope demonstrated that it shares a remarkable resemblance to beta Pictoris b.

    NASA Infrared Telescope facility Mauna Kea, Hawaii, USA, 4,207 m (13,802 ft) above sea level


    Keck Observatory, Maunakea, Hawaii, USA.4,207 m (13,802 ft), above sea level, showing also NASA’s IRTF and NAOJ Subaru

    Astrophysical Research Consortium 3.5 meter telescope at Apache Point, NM, USA

    ARC Astrophysics Research Consortium (ARC) Telescope The ARC 3.5m telescope is located at Apache Point ,Sunspot NM, USA, Altitude 2,788 meters (9,147 ft) II

    The 2MASS 0249 system is an appealing target for future studies. Most directly imaged planets are very close to their host stars, inhibiting detailed studies of the planets due to the bright light from the stars. In contrast, the very wide separation of 2MASS 0249 c from its host binary will make measurements of properties like its surface weather and composition much easier, leading to a better understanding of the characteristics and origins of gas-giant planets.

    This work is accepted for publication in The Astronomical Journal.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.
    stem
    Stem Education Coalition

    The CFH observatory hosts a world-class, 3.6 meter optical/infrared telescope. The observatory is located atop the summit of Mauna Kea, a 4200 meter, dormant volcano located on the island of Hawaii. The CFH Telescope became operational in 1979. The mission of CFHT is to provide for its user community a versatile and state-of-the-art astronomical observing facility which is well matched to the scientific goals of that community and which fully exploits the potential of the Mauna Kea site.

    CFHT Telescope
    CFHT Interior
    CFHT

     
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