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  • richardmitnick 4:38 pm on October 5, 2016 Permalink | Reply
    Tags: , , CFHT, Malin 1,   

    From CFHT: “A new look at the largest known disk galaxy” 

    CFHT icon
    Canada France Hawaii Telescope

    10.5.16
    Contact
    Dr. Samuel Boissier
    Laboratoire d’Astrophysique de Marseille (AMU, CNRS).
    Phone number: +33 4 91 05 59 37
    samuel.boissier@lam.fr

    1
    Combination of 4 NGVS images of Malin 1, obtained with MegaCam camera on CFHT. An indication of the size is given in the figure to show the amazing size of the disk of the galaxy (in comparison, the Milky Way has only a diameter around 30 kpc). Image Credit: Boissier/A&A/ESO/CFHT

    CFHT MegaCam
    CFHT MegaCam

    In a publication recently accepted in Astronomy and Astrophysics, an international team involving French researchers from the Laboratoire d’Astrophysique de Marseille and Canadian researchers from NRC Herzberg and Queens University have studied Malin 1, a nearby galaxy that has been known only since the eighty’s and that shows an extremely large disk of gas and stars. The new observations of Malin 1, a prototype of the class of “giant low surface brightness galaxies” allowed the team to obtain new results in contradiction with one of the hypotheses concerning the formation of this type of galaxies.

    Because they are very diffuse and of low surface brightness, giant low surface brightness galaxies, yet massive, are difficult to observe and are still poorly known. They could represent a significant percentage of the galaxies in the universe, especially because we could have missed such objects in our galaxy surveys. It is thus important do study them and understand their formation and evolution. This is now possible owing to the new generation of telescopes and modern detectors, with higher sensitivity to low surface brightness than in the past.

    This paper presents for the first time deep images obtained at 6 different wavelengths, from the UV of the GUViCS project to the optical and near-infrared obtained in the context of the Next Generation Virgo Survey with MegaCam on CFHT. Originally, these large observational campaigns were planned to study the Virgo cluster, but they also allow us to study background objects like Malin 1. The images offer us a new view of this spectacular galaxy, the largest galactic disk known, with a diameter above 250 kilo-parsec (in comparison, our Milky Way is only about 30 kpc wide).

    The team of researchers extracted from these data the variation of the luminosity with the distance to the center of the galaxy, as well as the variation of the colors (corresponding to the ratios between the luminosity at various wavelengths). These colors strongly depends on the star formation history. The comparison of the observations with predictions of various numerical models allowed the team to estimate for the first time what must have been the history of star formation in the giant disk of Malin 1. It suggests that the giant disk has been in place for several Gyr, and that star formation proceed at a regular long-term rhythm despite the very low density.

    This result is important as it clearly contradicts a scenario proposed a few years ago predicting that these giant galaxies are formed during violent interactions. Moreover, in the context of the cosmological formation of galaxies, numerous fusions and interaction should have perturbed the disk of Malin 1. The formation of such a structure and its survival for very long time offers then a challenge for cosmological simulations of the formation of galaxies.

    What is the future of Malin 1? The giant disk contains a large quantity of gas in which star formation will keep proceeding at a low rate for billions of years, increasing progressively the stellar mass of the galaxy. Unless another galaxy comes in the picture to interact with Malin 1 and totally change its destiny. Few galaxies, however, may play this role as Malin 1 is a relatively isolated galaxy.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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

     
  • richardmitnick 10:10 am on October 1, 2016 Permalink | Reply
    Tags: A galaxy in distress: the spectacular tails of ionized gas in NGC 4569 the most massive spiral galaxy in the Virgo cluster, , , CFHT,   

    From CFHT: “A galaxy in distress: the spectacular tails of ionized gas in NGC 4569, the most massive spiral galaxy in the Virgo cluster” 

    CFHT icon
    Canada France Hawaii Telescope

    Feb 8 2016 [Just appeared in social media.]
    Alessandro Boselli
    Laboratoire d’Astrophysique de Marseille
    38, rue Joliot-Curie
    F-13388 Marseille cedex 13
    France

    An international team led by researchers from the Laboratoire d’Astrophysique de Marseille (LAM) has used MegaCam on CFHT to observe NGC 4569, the most massive spiral galaxy in the Virgo cluster. They observed, for the first time, spectacular tails of ionized gas that extend for over 300,000 light years, five times larger than NGC 4569 itself! This observation confirms that ram pressure stripping due to the intracluster medium is depriving NGC 4569 of its gas reservoir. This important constraint must be taken into account in any cosmological model striving to incorporate the effect of environment on the evolution of galaxies. The result also shows that MegaCam at CFHT is now a second-to-none world-class facility to study gas stripping and opens up a promising new avenue for understanding the role of environment in the evolution of galaxies.

    CFHT MegaCam
    CFHT MegaCam

    1
    The colour image of the galaxy NGC 4569 in the Virgo cluster, obtained with MegaCam at the CFHT. The red filaments at the right of the galaxy show the ionised gas removed by ram pressure. This is about 95% of the gas reservoir of the galaxy needed to feed the formation of new stars (image ©2015 CFHT/Coelum).

    Galaxies are not distributed uniformly throughout the universe. Some are found in dense clusters that can contain hundred to thousands of galaxies. Astrophysicists suspect that living in a cluster environment can have a strong influence in the way galaxies evolve. The tell-tail signs have long been recognized: for instance, compared to less dense regions, clusters contain proportionally more elliptical galaxies (spheroidal systems with little to no gas and dust) and fewer spirals (gas rich disky systems in which new stars are continuously formed from the gas in the interstellar medium). And even the few spiral galaxies found in clusters generally contain less gas and have an older population of stars than isolated spiral galaxies.

    Several mechanisms have been proposed to explain the difference observed between galaxies in different environments. First, when two galaxies interact, tidal forces tend to rip apart and disrupt the outermost, less gravitationally bound and most diffuse parts. A second mechanism is the “dynamical pressure” exerted on the interstellar medium of a galaxy as it travels through the hot, diffuse medium that permeates the space in between galaxies, a process known as `ram pressure stripping’ (a biker travelling at high speed would experience a similar kind of pressure from the ambient air!). These two processes are able to lift gas from the disks of spiral galaxies, and therefore inhibit the formation of new stars. There is also a third mechanism that is thought to affect mostly the most massive galaxies: these galaxies host very massive black holes at their centres, and the energy liberated by the accretion onto these black holes, injected into the surrounding medium, can unbind the gas.

    Identifying which of these processes is dominant is critical to constrain cosmological simulations that follow the evolution of galaxies. Observationally, however, observing the low density gas as it is being stripped is a tremendous challenge. The MegaCam Camera on the Canada France Hawaii Telescope (CFHT) has recently been equipped with a new, high efficient narrow-band filter that isolates the H-alpha emission line from the ionized gas, allowing it to be detected with high efficiency.

    An international team led by researchers from the Laboratoire d’Astrophysique de Marseille (LAM) has used this instrument to observe NGC 4569, the most massive spiral galaxy in the Virgo cluster (at 45 million light years, the massive cluster of galaxies closest to the Milky Way). The Virgo cluster is still evolving, and therefore offers the opportunity to observe the transformation of galaxies as it takes place. NGC 4569 is moving through the cluster at a staggering 1200 km/s. The H-alpha image obtained with MegaCam at CFHT shows for the first time spectacular tails of ionized gas that extend for over 300,000 light years, five times larger than NGC 4569 itself ! This observation confirms that ram pressure stripping due to the intracluster medium is depriving NGC 4569 of its gas reservoir. An estimate of the mass of gas in these tails shows that 95% of the interstellar medium has already been removed from the disk of the galaxy, greatly limiting its ability to form new stars.

    For a galaxy as massive as NGC 4569, it is perhaps surprising that internal gravitational forces are not strong enough to hold the gas together, counteracting the action of ram pressure stripping. Indeed, in cosmological models, it is hypothesised that in such massive galaxies, it is the activity related to the central supermassive black hole to cause the gas to be lost. The new observations show instead that the dominant effect is ram pressure: this important constraint must be taken into account in any cosmological model striving to incorporate the effect of environment on the evolution of galaxies.

    The result also shows that MegaCam at CFHT is now a second-to-none world-class facility to study gas stripping and opens up a promising new avenue for understanding the role of environment in the evolution of galaxies.

    Scientific article

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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

     
  • richardmitnick 9:50 am on October 1, 2016 Permalink | Reply
    Tags: , , , CFHT,   

    From CFHT: “An unexpected use of large optical telescope: Imaging the small scale structure of the diffuse interstellar medium” 

    CFHT icon
    Canada France Hawaii Telescope

    7.12.16 [Just appeared in social media.]
    Information:
    Media contact
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    (808) 885-3121
    mary@cfht.hawaii.edu

    Science contacts
    Marc-Antoine Miville-Deschênes
    IAS (CNRS/Université Paris Sud/Université Paris-Saclay)
    mamd@ias.u-psud.fr
    Tel: 01 69 85 85 79

    Pierre-Alain Duc
    AIM (CEA/CNRS/Université Paris Diderot/Université Paris-Saclay)
    paduc@cea.fr
    Tel:01 69 08 92 68

    By combining multi-wavelength data obtained from space with Planck and WISE, and from the ground with MegaCam on CFHT, a team of researchers has revealed the structure of the diffuse interstellar medium over several square degrees with unprecedented details. In particular, this study reveals the statistical properties of interstellar turbulence over a wide range of scales, from 0.01 to 10 pc.

    CFHT MegaCam
    CFHT MegaCam

    ESA/Planck
    ESA/Planck

    NASA/WISE Telescope
    NASA/WISE Telescope

    1
    Optical images in true colours of the cirrus field obtained with MegaCam on the CFHT. Image credits: MATLAS collaboration, Pierre-Alain Duc.

    The main innovation of this work is the use of a large optical telescope (the CFHT) to study the structure of the interstellar medium at high resolution and on a large area on the sky, something that is very challenging to obtain with more classical observations done in the infrared. This mapping of these interstellar cirrus clouds located within a few hundred parsec from the Sun can be done because interstellar dust grains scatter starlight. This scattered light has been detected for decades by optical telescopes. Here it is the first time that is exploited scientifically to study the structure of interstellar clouds which is composed of faint filamentary structures of various sizes. The result obtained benefit from specific image processing and data acquisition techniques developed in the context of the MATLAS Large Program at CFHT that aims at detecting faint diffuse emission around galaxies.

    2
    Combined power spectrum : black is Planck radiance, red is WISE and blue is MegaCam. The units of the y axis are arbitrary; each power spectrum was scaled in order to match the others. For each power spectrum, we show data points corresponding to scales larger than the beam and where the power is above the noise component. The data points shown here are noise subtracted and divided by the beam function. The best fit gives P(k) ~ k^(2.9±0.1). Figure from Miville-Deschênes et al. 2016.

    One advantage of the high angular resolution provided by the CFHT data is to eventually reach the angular scale at which turbulent energy dissipates. Understanding the exact process by which kinetic energy is dissipated and heats gas is essential. It is key in the formation of dense structures that lead to the formation of stars. For instance, recent studies based on Herschel observations of molecular clouds have revealed the presence of filaments with widths of 0.1 pc that seem constant whatever their mass. This observational fact has been attributed to the energy dissipation process, namely ambipolar diffusion (friction between neutrals and ions). The present study shows that the dissipation scale in the interstellar medium is smaller than 0.01 pc which brings important constraints on the exact process resposible for this dissipation.

    These results emphasize the fact that scattered light from cirrus, an important source of pollution for deep imaging destined to mapping diffuse structures around massive galaxies, is carrying potentially precious information about the nature of the physical processes involved in the evolution of matter in our own galaxy.

    Additional information
    CNRS/INSU press release (In French only)
    Scientific paper

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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

     
  • richardmitnick 9:16 am on October 1, 2016 Permalink | Reply
    Tags: , , CFHT, Dwarf planet designated 2015 RR245,   

    From CFHT: “New Distant Dwarf Planet Beyond Neptune” 

    CFHT icon
    Canada France Hawaii Telescope

    July 11, 2016 [Just appeared in social media.]
    Media contacts:
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    (808) 885-3121
    mary@cfht.hawaii.edu

    Thandi Fletcher
    The University of British Columbia
    (604) 822-2234
    thandi.fletcher@ubc.ca

    Science contacts:
    Dr. Michele Bannister
    Postdoctoral Fellow with the Outer Solar System Origins Survey
    Department of Physics and Astronomy
    University of Victoria, Victoria BC
    micheleb@uvic.ca
    tel: +1 250 580 3085

    Dr. Jean-Marc Petit
    Institut UTINAM – UMR CNRS 6213
    Observatoire de Besancon
    41 bis Avenue de l’Observatoire BP 1615
    Jean-Marc.Petit@normalesup.org
    tel: (33) [0]695 207 174

    Dr Ying-Tung (Charles) Chen 陳英同, IAA
    Academia Sinica, Taipei
    ytchen@asiaa.sinica.edu.tw
    tel: +886-2-2366-5356

    An international team of astronomers have discovered a new dwarf planet orbiting in the disk of small icy worlds beyond Neptune. The new object is roughly 700 kilometers in size and has one of the largest orbits for a dwarf planet. Designated 2015 RR245 by the International Astronomical Union’s Minor Planet Center, it was found using the Canada-France-Hawaii Telescope on Maunakea, Hawaii, as part of the ongoing Outer Solar System Origins Survey (OSSOS).

    1
    Discovery images of RR245. The images show RR245’s slow motion across the sky over three hours. Credit OSSOS team.

    “The icy worlds beyond Neptune trace how the giant planets formed and then moved out from the Sun. They let us piece together the history of our Solar System. But almost all of these icy worlds are painfully small and faint: it’s really exciting to find one that’s large and bright enough that we can study it in detail.” said Dr Michele Bannister of the University of Victoria in British Columbia, who is a postdoctoral fellow with the Survey.

    National Research Council of Canada’s Dr JJ Kavelaars first sighted RR245 in February 2016 in the OSSOS images from September 2015.”There it was on the screen— this dot of light moving so slowly that it had to be at least twice as far as Neptune from the Sun.” said Bannister.

    The team became even more excited when they realized that the object’s orbit takes it more than 120 times further from the Sun than Earth. The size of RR245 is not yet exactly known, as its surface properties need further measurement. “It’s either small and shiny, or large and dull.” said Bannister.

    2
    Rendering of the orbit of RR245 (orange line). Objects as bright or brighter than RR245 are labeled. The blue circles show the projected orbits of the major planets. The Minor Planet Center describes the object as the 18th largest in the Kuiper Belt. Credit: Alex Parker OSSOS team.

    The vast majority of the dwarf planets like RR245 were destroyed or thrown from the Solar System in the chaos that ensued as the giant planets moved out to their present positions: RR245 is one of the few dwarf planets that has survived to the present day — along with Pluto and Eris, the largest known dwarf planets. RR245 now circles the Sun among the remnant population of tens of thousands of much smaller trans-Neptunian worlds, most of which orbit’s is unseen.

    Worlds that journey far from the Sun have exotic geology with landscapes made of many different frozen materials, as the recent flyby of Pluto by the New Horizons spacecraft showed.

    After hundreds of years further than 12 billion km (80 astronomical units, AU) from the Sun, RR245 is travelling towards its closest approach at 5 billion km (34 AU), which it will reach around 2096. RR245 has been on its highly elliptical orbit for at least the last 100 million years.

    As RR245 has only been observed for one of the seven hundred years it takes to orbit the Sun, where it came from and how its orbit will slowly evolve in the far future is still unknown; its precise orbit will be refined over the coming years, after which RR245 will be given a name. As discoverers, the OSSOS team can submit their preferred name for RR245 to the International Astronomical Union for consideration.

    “OSSOS was designed to map the orbital structure of the outer Solar System to decipher its history.” said Prof. Brett Gladman of the University of British Columbia in Vancouver. “While not designed to efficiently detect dwarf planets, we’re delighted to have found one on such an interesting orbit”.

    RR245 is the largest discovery and the only dwarf planet found by OSSOS, which has discovered more than five hundred new trans-Neptunian objects. “OSSOS is only possible due to the exceptional observing capabilities of the Canada-France-Hawaii Telescope. CFHT is located at one of the best optical observing locations on Earth, is equipped with an enormous wide-field imager, and can quickly adapt its observing each night to new discoveries we make. This facility is truly world leading.” said Gladman.

    Previous surveys have mapped almost all the brighter dwarf planets. 2015 RR245 may be one of the last large worlds beyond Neptune to be found until larger telescopes, such as LSST, come online in the mid 2020s.

    OSSOS involves a collaboration of fifty scientists at institutes and universities from around the world.

    OSSOS is based on observations obtained with MegaPrime/MegaCam, a joint project of the Canada-France-Hawaii Telescope (CFHT) 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 Hawaii, with OSSOS receiving additional access due to contributions from the Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan.

    Additional information
    International Astronomical Union electronic discovery announcement
    International Astronomical Union orbital information
    Chinese release, ASIAA-Taiwan site
    OSSOS Project website

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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

     
  • richardmitnick 10:45 am on July 26, 2016 Permalink | Reply
    Tags: An Extremely Weak Magnetic Field in a White Dwarf, , , CFHT,   

    From ING: “An Extremely Weak Magnetic Field in a White Dwarf” 

    Isaac Newton Group of Telescopes Logo
    Isaac Newton Group of Telescopes

    A team of astronomers reports the discovery of one of the very weakest magnetic fields ever securely detected in a white dwarf. The observation was made using the ISIS spectropolarimeter on the William Herschel Telescope (WHT), in just one hour of exposure time and using the red and the blue arms of the spectrograph. This is part of a large survey of bright white dwarfs to search for such weak magnetic fields.

    1
    First observation of Zeeman splitting in the core of Hydrogen alpha due to a field of about 60 kilogauss in WD2047+372. The ISIS observation is in blue, the ESPaDOnS observation (at higher resolving power) is shown in red. The circular polarisation spectrum is shown below the intensity profile, shifted up by +0.4 to facilitate comparison with the spectral line profile. The green lines bracketing the circular polarisation are ± one sigma. Figure extracted from Landstreet et al. (2016).

    The strength of the magnetic field found in LTT 16093 = WD2047+372 is only about 60 kilogauss (6 teslas), 2 or 3 orders of magnitude smaller than the typical fields of tens of megagauss found in a few percent of white dwarfs. The field was marginally detected in polarimetery, but clear Zeeman splitting into a triplet was present in the sharp core of Hydrogen alpha. This first detection using ISIS was confirmed by a spectropolarimetric observation a month later with the higher resolving power spectropolarimeter ESPaDOnS on the Canada-France-Hawaii Telescope [CFHT].

    CFHT ESPaDOns preferred
    CFHT ESPaDOns

    CFHT Telescope, Mauna Kea, Hawaii, USA
    CFHT Interior
    CFHT

    It is not yet understood how the magnetic fields of white dwarfs are formed, or how they evolve during white dwarf cooling. In spite of many detections of megagauss fields in white dwarfs, mostly very faint, little is known about the low-field regime, and very little modelling of the fields of individual white dwarfs is available. This current ISIS survey is intended to increase the very small sample and to provide data for detailed modelling, and ultimately to provide data to constrain field formation scenarios.

    It is found that ISIS is a very powerful tool for searches for such weak fields; it is able to detect fields of tens of kilogauss using either Hydrogen-alpha spectroscopy or spectropolarimetry of Hydrogen or Helium line wings, or both, in white dwarfs fainter than V = 15.

    More information:

    J. D. Landstreet, S. Bagnulo, A. Martin, and G. Valyavin, 2016, Discovery of an extremely weak magnetic field in the white dwarf LTT 16093 WD2047+372, A&A, 591, A80 [ADS ].

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    Isaac Newton Group telescopes
    Isaac Newton Group telescopes

    ING William Herschel Telescope
    ING William Herschel Interior
    ING William Herschel Telescope

     
  • richardmitnick 3:47 pm on July 12, 2016 Permalink | Reply
    Tags: , , , CFHT   

    From CFHT: “An unexpected use of large optical telescope… 

    CFHT icon
    Canada France Hawaii Telescope

    … Imaging the small scale structure of the diffuse interstellar medium”

    7.12.16

    Media contact
    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    (808) 885-3121
    mary@cfht.hawaii.edu

    Science contacts
    Marc-Antoine Miville-Deschênes
    IAS (CNRS/Université Paris Sud/Université Paris-Saclay)
    mamd@ias.u-psud.fr
    Tel: 01 69 85 85 79

    Pierre-Alain Duc
    AIM (CEA/CNRS/Université Paris Diderot/Université Paris-Saclay)
    paduc@cea.fr
    Tel:01 69 08 92 68

    1
    Optical images in true colours of the cirrus field obtained with MegaCam on the CFHT. Image credits: MATLAS collaboration, Pierre-Alain Duc.

    CFHT Megacam
    CFHT Megacam

    By combining multi-wavelength data obtained from space with Planck and WISE, and from the ground with MegaCam on the CFHT, a team of researchers has revealed the structure of the diffuse interstellar medium over several square degrees with unprecedented details. In particular, this study reveals the statistical properties of interstellar turbulence over a wide range of scales, from 0.01 to 10 pc.

    ESA/Planck
    ESA/Planck

    NASA/Wise Telescope
    NASA/WISE

    The main innovation of this work is the use of a large optical telescope (the CHFT) to study the structure of the interstellar medium at high resolution and on a large area on the sky, something that is very challenging to obtain with more classical observations done in the infrared. This mapping of these interstellar cirrus clouds located within a few hundred parsec from the Sun can be done because interstellar dust grains scatter starlight. This scattered light has been detected for decades by optical telescopes. Here it is the first time that is exploited scientifically to study the structure of interstellar clouds which is composed of faint filametary structures of various sizes. The result obtained benefit from specific image processing and data acquisition techniques developped in the context of the MATLAS Large Program of the CHFT that aims at detecting faint diffuse emission around galaxies.

    3
    Combined power spectrum : black is Planck radiance, red is WISE and blue is MegaCam. The units of the y axis are arbitrary; each power spectrum was scaled in order to match the others. For each power spectrum, we show data points corresponding to scales larger than the beam and where the power is above the noise component. The data points shown here are noise subtracted and divided by the beam function. The best fit gives P(k) ~ k^(2.9±0.1). Figure from Miville-Deschênes et al. 2016.

    One advantage of the high angular resolution provided by the CFHT data is to eventually reach the angular scale at whcih turbulent energy dissipates. Understanding the exact process by which kinetic energy is dissipated and heat the gas is essential as it is key in the formation of dense structures that lead to the formation of stars. For instance, recent studies based on Herschel observations of molecular clouds have revealed the presence of filaments with width of 0.1 pc that seem constant whatever their mass. This observational fact has been attributed to the energy dissipation process, namely the ambipolar diffusion (friction between neutrals and ions). The present study is showing that the dissipation scale in the interstellar medium is smaller than 0.01 pc which brings important constraints on the exact process resposible for this dissipation.

    These results are emphasizing the fact that scattered light from cirrus, an important source of pollution for deep imaging destined to mapping diffuse structures around massive galaxies, is carrying potentially precious information about the nature of the physical processes involved in the evolution of matter in our own galaxy.

    Science paper:
    Probing interstellar turbulence in cirrus with deep optical imaging: no sign of energy dissipation at 0.01 pc scale

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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

     
  • richardmitnick 2:18 pm on July 11, 2016 Permalink | Reply
    Tags: , , CFHT,   

    From CFHT: “New Distant Dwarf Planet Beyond Neptune” 

    CFHT icon
    Canada France Hawaii Telescope

    7.11.16

    Mary Beth Laychak
    Canada-France-Hawaii Telescope
    (808) 885-3121
    mary@cfht.hawaii.edu

    Thandi Fletcher
    The University of British Columbia
    (604) 822-2234
    thandi.fletcher@ubc.ca

    Science contacts:
    Dr. Michele Bannister
    Postdoctoral Fellow with the Outer Solar System Origins Survey
    Department of Physics and Astronomy
    University of Victoria, Victoria BC
    micheleb@uvic.ca
    tel: +1 250 580 3085

    Dr. Jean-Marc Petit
    Institut UTINAM – UMR CNRS 6213
    Observatoire de Besancon
    41 bis Avenue de l’Observatoire BP 1615
    Jean-Marc.Petit@normalesup.org
    tel: (33) [0]695 207 174

    Dr Ying-Tung (Charles) Chen 陳英同, IAA
    Academia Sinica, Taipei
    ytchen@asiaa.sinica.edu.tw
    tel: +886-2-2366-5356

    1
    Discovery images of RR245. The images show RR245’s slow motion across the sky over three hours (.gif file). Credit OSSOS team.

    An international team of astronomers have discovered a new dwarf planet orbiting in the disk of small icy worlds beyond Neptune. The new object is roughly 700 kilometers in size and has one of the largest orbits for a dwarf planet. Designated 2015 RR245 by the International Astronomical Union’s Minor Planet Center, it was found using the Canada-France-Hawaii Telescope on Maunakea, Hawaii, as part of the ongoing Outer Solar System Origins Survey (OSSOS).

    “The icy worlds beyond Neptune trace how the giant planets formed and then moved out from the Sun. They let us piece together the history of our Solar System. But almost all of these icy worlds are painfully small and faint: it’s really exciting to find one that’s large and bright enough that we can study it in detail.” said Dr Michele Bannister of the University of Victoria in British Columbia, who is a postdoctoral fellow with the Survey.

    National Research Council of Canada’s Dr JJ Kavelaars first sighted RR245 in February 2016 in the OSSOS images from September 2015.”There it was on the screen— this dot of light moving so slowly that it had to be at least twice as far as Neptune from the Sun.” said Bannister.

    The team became even more excited when they realized that the object’s orbit takes it more than 120 times further from the Sun than Earth. The size of RR245 is not yet exactly known, as its surface properties need further measurement. “It’s either small and shiny, or large and dull.” said Bannister.

    2
    Rendering of the orbit of RR245 (orange line). Objects as bright or brighter than RR245 are labeled. The Minor Planet Center describes the object as the 18th largest in the Kuiper Belt. Credit: Alex Parker OSSOS team.

    The vast majority of the dwarf planets like RR245 were destroyed or thrown from the Solar System in the chaos that ensued as the giant planets moved out to their present positions: RR245 is one of the few dwarf planets that has survived to the present day — along with Pluto and Eris, the largest known dwarf planets. RR245 now circles the Sun among the remnant population of tens of thousands of much smaller trans-Neptunian worlds, most of which orbit’s is unseen.

    Worlds that journey far from the Sun have exotic geology with landscapes made of many different frozen materials, as the recent flyby of Pluto by the New Horizons spacecraft showed.

    After hundreds of years further than 12 billion km (80 astronomical units, AU) from the Sun, RR245 is travelling towards its closest approach at 5 billion km (34 AU), which it will reach around 2096. RR245 has been on its highly elliptical orbit for at least the last 100 million years.

    As RR245 has only been observed for one of the seven hundred years it takes to orbit the Sun, where it came from and how its orbit will slowly evolve in the far future is still unknown; its precise orbit will be refined over the coming years, after which RR245 will be given a name. As discoverers, the OSSOS team can submit their preferred name for RR245 to the International Astronomical Union for consideration.

    “OSSOS was designed to map the orbital structure of the outer Solar System to decipher its history.” said Prof. Brett Gladman of the University of British Columbia in Vancouver. “While not designed to efficiently detect dwarf planets, we’re delighted to have found one on such an interesting orbit”.

    RR245 is the largest discovery and the only dwarf planet found by OSSOS, which has discovered more than five hundred new trans-Neptunian objects. “OSSOS is only possible due to the exceptional observing capabilities of the Canada-France-Hawaii Telescope. CFHT is located at one of the best optical observing locations on Earth, is equipped with an enormous wide-field imager, and can quickly adapt its observing each night to new discoveries we make. This facility is truly world leading.” said Gladman.

    Previous surveys have mapped almost all the brighter dwarf planets. 2015 RR245 may be one of the last large worlds beyond Neptune to be found until larger telescopes, such as LSST, come online in the mid 2020s.

    OSSOS involves a collaboration of fifty scientists at institutes and universities from around the world.

    OSSOS is based on observations obtained with MegaPrime/MegaCam, a joint project of the Canada-France-Hawaii Telescope (CFHT) 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 Hawaii, with OSSOS receiving additional access due to contributions from the Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan.

    See the full article here .

    Please help promote STEM in your local schools.

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    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

     
  • richardmitnick 11:49 am on July 2, 2016 Permalink | Reply
    Tags: , , CFHT, ,   

    From New Horizons: “From Canada to Pluto and Beyond” 

    NASA image

    NASA

    NASA/New Horizons spacecraft

    New Horizons

    July 1, 2016
    Alex Parker, Southwest Research Institute

    Nature is a common theme in Canadian literature, with desolate, remote landscapes often playing a role. It should come as no surprise, then, that Canada had a hand in writing the latest chapter in the story of Pluto, the most desolate and remote landscape ever explored.

    To mark the first Canada Day (July 1) since the Pluto flyby, I wanted to share some of the ways that Canadian efforts have supported the New Horizons mission to Pluto and beyond.

    A number of New Horizons team members are from Canada or were trained there in one way or another. I studied for my PhD at the University of Victoria in British Columbia; my PhD was in astrophysics, a field in which Canada is renowned as a global leader. Canada’s national partnership in the twin 8-meter Gemini observatories allowed me to pursue research in planetary astronomy, pushing the limits of what can be done with ground-based astronomical imaging without adaptive optics to explore the properties of binary systems in the Kuiper Belt. It was this work that prepared me for and eventually steered me toward the New Horizons mission, where I joined the team that discovered 2014 MU69, the post-Pluto target for a potential New Horizons extended mission.

    1
    The Canada-France-Hawaii Telescope (left) and the Gemini North observatory (right), at Mauna Kea, Hawaii, USA. These two facilities both collected critical images in support of the New Horizons mission under Canadian-led programs. Credit: Alex Parker

    Perhaps the most crucial Canadian contributions are in an area with a very long history: navigating a ship by the stars. During New Horizons’ approach to Pluto last year, it was a made-in-Canada star map that helped guide the way. National Research Council (NRC) of Canada scientists at the Canadian Astronomy Data Centre (CADC) in British Columbia used data collected from the Canada-France-Hawaii Telescope (CFHT) to assemble a detailed navigational star map for the mission, which was used by the Navigation and Hazards teams to keep the spacecraft on-course and safe from harm.

    Dr. Stephen Gwyn and Dr. JJ Kavelaars, both at the NRC-CADC, have worked to support the New Horizons mission for years. JJ Kavelaars was my PhD supervisor, and both he and Stephen Gwyn taught me much of what I know about the astrometric and image processing techniques needed to find and track New Horizons’ potential post-Pluto target, 2014 MU69.

    Gwyn developed and maintains MegaPipe, the data processing service that helps turn raw CFHT images into precisely-calibrated star maps, among other things. Using data collected from CFHT’s extremely well-calibrated MegaCam imager especially for the Pluto mission, Gwyn created a catalog the stars that would stand as a backdrop for Pluto during the flyby. The purpose of the catalog was to provide extremely precise locations and properties of the stars that would appear in New Horizons images on approach, so they could be used as navigational aids.

    Frédéric Pelletier, a former Canadian Space Agency engineer from Quebec, was the KinetX Deputy Navigation Team Chief for the Pluto flyby. He and his team compared imagery from New Horizons to the CFHT star map to determine exactly the path that New Horizons was on with respect to Pluto, and adjust its course to achieve the planned flyby. The targeting was precise enough to fly New Horizons through the shadows of both Pluto and Charon. This allowed New Horizons to examine Pluto’s atmosphere backlit by the sun, and perform detailed analysis of its chemical makeup. The Atmospheres science team is led by Dr. Randy Gladstone at SwRI, who grew up in Canada and attended the University of British Columba.

    Both Gwyn and Kavelaars are involved in our continued tracking of 2014 MU69, providing their expertise on matters of extremely high-precision astrometry of both stars and Kuiper Belt Objects. The CFHT star map is still in use for determining the precise orbit of 2014 MU69, and Kavelaars has led a Gemini Observatory program to track and refine the orbits of many other Kuiper Belt objects that New Horizons would study at long range during an extended mission.

    If an extended mission is approved, these efforts will continue to help New Horizons find its way into the unknown as it flies to worlds in the outer solar system more distant than have ever been explored.

    See the full article here .

    Please help promote STEM in your local schools.

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    The New Horizons mission is helping us understand worlds at the edge of our solar system by making the first reconnaissance of the dwarf planet Pluto and by venturing deeper into the distant, mysterious Kuiper Belt – a relic of solar system formation.

    The Journey

    New Horizons launched on Jan. 19, 2006; it swung past Jupiter for a gravity boost and scientific studies in February 2007, and conducted a six-month-long reconnaissance flyby study of Pluto and its moons in summer 2015, culminating with Pluto closest approach on July 14, 2015. As part of an extended mission, pending NASA approval, the spacecraft is expected to head farther into the Kuiper Belt to examine another of the ancient, icy mini-worlds in that vast region, at least a billion miles beyond Neptune’s orbit.

    Sending a spacecraft on this long journey is helping us to answer basic questions about the surface properties, geology, interior makeup and atmospheres on these bodies.

    New Science

    The National Academy of Sciences has ranked the exploration of the Kuiper Belt – including Pluto – of the highest priority for solar system exploration. Generally, New Horizons seeks to understand where Pluto and its moons “fit in” with the other objects in the solar system, such as the inner rocky planets (Earth, Mars, Venus and Mercury) and the outer gas giants (Jupiter, Saturn, Uranus and Neptune).

    Pluto and its largest moon, Charon, belong to a third category known as “ice dwarfs.” They have solid surfaces but, unlike the terrestrial planets, a significant portion of their mass is icy material.

    Using Hubble Space Telescope images, New Horizons team members have discovered four previously unknown moons of Pluto: Nix, Hydra, Styx and Kerberos.

    A close-up look at these worlds from a spacecraft promises to tell an incredible story about the origins and outskirts of our solar system. New Horizons is exploring – for the first time – how ice dwarf planets like Pluto and Kuiper Belt bodies have evolved over time.

    The Need to Explore

    The United States has been the first nation to reach every planet from Mercury to Neptune with a space probe. New Horizons is allowing the U.S. to complete the initial reconnaissance of the solar system.

    A Team Approach

    The Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate.

    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

     
  • richardmitnick 10:34 am on June 21, 2016 Permalink | Reply
    Tags: , , CFHT, , Innovative Gemini/CHFT Partnership Explores a Hot Jupiter, Newborn Giant Planet Grazes its Sun   

    From Gemini and CFHT: “Innovative Gemini/CHFT Partnership Explores a Hot Jupiter” 

    NOAO

    Gemini Observatory
    Gemini Observatory

    CFHT icon
    Canada France Hawaii Telescope

    June 20, 2016
    Dr. Claire Moutou
    (CFHT, Hawaii)
    1-808-885-7944
    Dr. Lison Malo
    (CFHT, Hawaii)
    1-808-885-7944

    Dr. Jean-Francois Donati
    (IRAP, Toulouse, France)
    Phone: +33-561332917
    jean-francois.donati”@”irap.omp.eu

    The novel collaboration between the Gemini Observatory and Canada-France-Hawai‘i Telescope (CFHT) called GRACES (Gemini Remote Access to CFHT ESPaDOnS Spectrograph), helped to characterize a “hot Jupiter” around the T-Tauri star V830 Tau. The work appears in the current advanced online issue of the journal Nature.

    GRACES uses an innovative 270-meter fiber cable to transport light from the Gemini 8-meter telescope to the ESPaDOnS Spectrograph at CFHT. The system began operating in late 2015 and now is a popular option allowing Gemini and CFHT users to perform high-resolution optical spectroscopy with Gemini North’s larger mirror.

    The Nature paper is available online (subscription required) and is summarized in the press release from Observatoire Midi Pyrenees in Toulouse, France and CFHT that follows (release is reproduced verbatim from original):

    Newborn Giant Planet Grazes its Sun

    1
    Artistʻs view of a newborn giant planet like the one newly discovered at the immediate vicinity of the very active infant star V830 Tau, as might be seen by an observer located close to the giant planet. Credit: Mark A. Garlick markgarlick.com

    For the last 20 years the giant planets known as hot Jupiters have presented astronomers with a puzzle. How did they settle into orbits 100 times closer to their host stars than our own Jupiter is to the Sun? An international team of astronomers has announced this week [1] the discovery of a newborn hot Jupiter, orbiting an infant sun — only 2 million years old, the stellar equivalent of a week-old human baby. The discovery that hot Jupiters can already be present at such an early stage of star-planet formation represents a major step forward in our understanding of how planetary systems form and evolve.

    For this discovery, the team monitored a 2 million-year-old infant star called V830 Tau, located in the Taurus stellar nursery, some 430 light-years away. Over the 1.5 months of the campaign, a regular 4.9-day “wobble” in the velocity of the host star revealed a giant planet almost as massive as Jupiter, orbiting its host star at a distance of only one-twentieth that of the Sun to the Earth distance. “Our discovery demonstrates for the first time that such bodies can be generated at very early stages of planetary formation, and likely play a central role in shaping the overall architecture of planetary systems” explains Jean-François Donati, CNRS astronomer at IRAP / OMP [2] and lead author of a new paper in the current issue of the journal Nature.

    The team used the twin spectropolarimeters ESPaDOnS and Narval to monitor V830 Tau for a total of 47 hours.

    CFHT ESPaDOns preferred
    CFHT ESPaDOns

    4
    Narval, mounted at the 2-meter Télescope Bernard Lyot [4] (TBL) atop Pic du Midi in the French Pyrénées

    ESPaDOnS is mounted at the 3.6-m Canada-France-Hawaii Telescope [3] (CFHT) on Maunakea and can be fiber-fed from either CFHT itself, or via GRACES, a 300-m optical-fiber link from the nearby 8 meter Gemini North telescope. The team used ESPaDOnS in both modes, providing the opportunity to monitor the star using light from the Gemini North telescope when the instrument was unavailable at CFHT. The team also used Narval, mounted at the 2-meter Télescope Bernard Lyot [4] (TBL) atop Pic du Midi in the French Pyrénées. “Using all three telescopes was essential for monitoring regularly V830 Tau throughout our campaign and for detecting its giant planet” stresses Lison Malo, CFHT astronomer, a coauthor of the study and leader in coordinating the observations.

    In our Solar System, small rocky planets like the Earth are found near the Sun, whereas gas giants like Jupiter and Saturn orbit much further out. “The discovery in 1995 of a giant planet flying very close to its host star took us by surprise and revolutionized the field” recalls Claire Moutou, CNRS astronomer at CFHT and a coauthor of this new study. Theoretical work indicates that such planets can only form in the cold and icy outer regions of the protoplanetary disc in which both the central star and surrounding planets are born. Some, however, migrate inwards without falling into their host star, thus becoming hot Jupiters.

    “Planet formation models offer two competing explanations of how and when this migration of hot Jupiters occurred. Either it happened early while these planets were still forming, or much later, with some planets being kicked closer to their stars due to the interaction of multiple planets, or both” explains Clément Baruteau, CNRS astronomer at IRAP / OMP and a coauthor of this study. “Our discovery demonstrates that the first, earlier option is taking place; it revives the long-running debate about how and when this migration occurs, and brings us one step forward in our understanding of how planetary systems form”.

    Among the known hot Jupiters, some feature strongly-tilted or even upside-down orbits, suggesting they were knocked into close orbits by interactions with other planets or neighboring stars. Others orbit above the host star’s equator, hinting at a more gentle formation process in the form of an inward drift through the disc. “The young hot Jupiter we just detected comes as the first evidence that early disc migration is also happening” says Andrew Collier Cameron of the University of St Andrews, a coauthor of the study.

    References:
    1 The paper describing the discovery, published in Nature, is available here.

    2 IRAP (Institut de Recherche en Astrophysique et Planétologie) is a research lab part of OMP (Observatoire Midi-Pyrénées) located in Toulouse (France), and under dual supervision from CNRS / INSU (Centre National de la Recherche Scientifique / Institut National des Sciences de l’Univers) and UFTMiP / UPS (Université Fédérale Toulouse Midi-Pyrénées / Université Paul Sabatier)

    3 CFHT is operated by the National Research Council of Canada, CNRS/INSU in France and the University of Hawaii

    4 TBL is operated by IRAP / OMP, CNRS / INSU and UFTMiP / UPS

    View CFHT release.

    See the full article here .

    Please help promote STEM in your local schools.

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    Gemini North
    Gemini North, Hawai’i

    Gemini South
    Gemini South, Chile
    AURA Icon

    CFHT Telescope, Mauna Kea, Hawaii, USA
    CFHT Interior
    CFHT Telescope, Mauna Kea, Hawaii, USA

    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

    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.

     
  • richardmitnick 4:23 pm on January 1, 2016 Permalink | Reply
    Tags: , , CFHT, Supernova remnant   

    From CFHT: “Megacam image of the supernova remnant NGC 6979” 

    CFHT icon
    Canada France Hawaii Telescope

    1.1.16
    No writer credit found

    Temp 1

    Happy New Year!

    This Megacam image of the supernova remnant NGC 6979 looks a lot like fireworks. And it should, supernovae are formed when a star much more massive than the sun suddenly ends its life is an explosion.

    CFHT Megacam
    Megacam

    The star’s gas rapidly moves outward, colliding with neighboring gas and dust. These collisions cause the fireworks-esque colors and patterns seen in the image.

    The NGC 6979 image and all of our stunning Megacam images are created by Megacam along with one of our former CFHT resident astronomers, Jean-Charles Culliandre and Coelum Astronomia.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    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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