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  • richardmitnick 3:54 pm on February 28, 2017 Permalink | Reply
    Tags: , , , COSMOS field as imaged by the Hyper Suprime-Cam, HSC-SSP survey, NAOJ   

    From NAOJ: “First Public Data Release by the Hyper Suprime-Cam Subaru Strategic Program” 

    NAOJ

    NAOJ

    February 27, 2017

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    Figure 1: A color composite image in the g, r and i bands of a small piece of the COSMOS field, as imaged by the Hyper Suprime-Cam. This image contains thousands of galaxies as faint as 27th magnitude. The galaxies are seen at such large distances that the light from them has taken billions of years to reach us. The light from the faintest galaxies was emitted when the universe was less than 10 % of its present age. (Credit: Princeton University/HSC Project)

    Figuring out the fate of the Universe is one step closer. The first massive dataset of a “cosmic census” is released using the largest digital camera on the Subaru Telescope. Beautiful images are available for public at large.

    The first dataset from the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) was released to the public on February 27th, 2017. HSC-SSP is a large survey being done using HSC, which is an optical imaging camera mounted at the prime focus of the Subaru Telescope. HSC has 104 scientific CCDs (for a total of 870 million pixels) and a 1.77 square-degree field of view.

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    Figure 2: A HSC-SSP image of a massive cluster of galaxies in the Virgo constellation showing numerous strong gravitational lenses. The distance to the central galaxy is 5.3 billion light years, while the lensed galaxies, apparent as the arcs around the cluster, are much more distant. This is a composite image in the g, r, and i band, and has a spatial resolution of about 0.6 arcsecond. (Credit: NAOJ/HSC Project)

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    Figure 3: A color composite image in the g, r and i bands of UGC 10214 known as Tadpole Galaxy in the ELAIS-N1 region. The distance to this galaxy is about 400 million light years. The long tail of stars made by gravitational interaction due to the galactic encounter is characteristic. (Credit: NAOJ/HSC Project)

    The National Astronomical Observatory of Japan (NAOJ) has embarked on the HSC-SSP survey in collaboration with the Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU) in Japan, the Academia Sinica Institute of Astronomy and Astrophysics (ASIAA) in Taiwan, and Princeton University in the United States. The project will take 300 nights over 5-6 years. This survey consists of three layers; Wide, Deep, and UltraDeep, using optical and near infrared wavelengths in five broad bands (g, r, i, z, y) and four narrow-band filters.

    This release includes data from the first 1.7 years (61.5 nights of observations beginning in 2014). The observed areas covered by the Wide, Deep, and UltraDeep layers are 108, 26, and 4 square degrees, respectively. The limiting magnitudes, which refer to the depth (Note) of the observations, are 26.4, 26.6 and 27.3 mag in r-band (about 620 nm wavelength), respectively, allowing observations of some of the most distant galaxies in the universe. In the multi-band images, images are extremely sharp, with star images only 0.6 to 0.8 arcseconds across. 1 arcsecond equals 3600th part of a degree. These high-quality data will allow a unprecedented view into the nature and evolution of galaxies and dark matter. This first public dataset already contains 70 million galaxies and stars. It demonstrates that HSC-SSP is making the most of the performance of the Subaru Telescope and HSC. In 2015, using HSC observations over 2.3 square degrees of sky, nine clumps of dark matter, each weighing as much a galaxy cluster were discovered from their weak lensing signature (Miyazaki et al. 2015, ApJ 807, 22, “Properties of Weak Lensing Clusters Detected on Hyper Suprime-Cam 2.3 Square Degree Field”). The HSC-SSP data release covers about 50 times more sky than was used in this study, showing the potential of these data to reveal the statistical properties of dark matter.

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    4a
    4b

    Figure 4: Survey area of HSC-SSP. Blue color shows the area of the Wide layer data included in the data release, green Deep, and red UltraDeep, respectively. (Credit: NAOJ/HSC Project)

    The total amount of data taken so far comprises 80 terabytes, which is comparable to the size of about 10 million images by a general digital camera. Since it is difficult to search such a huge dataset with standard tools, NAOJ has developed a dedicated database and interface for ease of access and use of the data.

    “Since 2014, we have been observing the sky with HSC, which can capture a wide-field image with high resolution,” said Dr. Satoshi Miyazaki, the leader of the HSC-SSP. “We believe the data release will lead to many exciting astronomical results, from exploring the nature of dark matter and dark energy, as well as asteroids in our own solar system objects and galaxies in the early universe. SSP team members are now preparing a number of scientific papers based on these data. We plan to publish them in a special issue of the Publications of Astronomical Society of Japan. Moreover, we hope that interested members of the public will also access the data and enjoy the real universe imaged by the Subaru telescope, one of the largest the world.”

    Funding for the HSC Project was provided in part by the following grants: Grant-in-Aid for Scientific Research (B) JP15340065; Grant-in-Aid for Scientific Research on Priority Areas JP18072003; and the Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST) entitled, “Uncovering the Origin and Future of the Universe: ultra-wide-field imaging and spectroscopy reveal the nature of dark matter and dark energy.”

    Note:

    “Depth” of an observation refers to how dim objects can be studied. The light collection power of large aperture mirror (8.2 m for the Subaru Telescope) is the crucial factor, as well as the exposure time. For astronomical objects of the same intrinsic brightness, depth is literally how far one can look.

    Links:

    HSC-SSP Public data release site
    HSC-SSP Website
    HSC Project Website
    Image of M31 Heralds the Dawn of HSC’s Productivity (July 30, 2013 Subaru Tele-scope Topics)
    Hyper Suprime-Cam Ushers in a New Era of Observational Astronomy (September 12, 2012 Subaru Telescope Topics)

    See the full article here .

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    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 4:07 pm on February 2, 2017 Permalink | Reply
    Tags: , , , , , NAOJ, Tail of Stray Black Hole hiding in the Milky Way   

    From NAOJ: “Tail of Stray Black Hole hiding in the Milky Way” 

    NAOJ

    NAOJ

    2017 Feb 02
    No writer credit found

    By analyzing the gas motion of an extraordinarily fast-moving cosmic cloud in a corner of the Milky Way, astronomers found hints of a wandering black hole hidden in the cloud. This result marks the beginning of the search for quiet black holes; millions of such objects are expected to be floating in the Milky Way although only dozens have been found to date.

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    Figure 1. Artist’s impression of a stray black hole storming through a dense gas cloud. The gas is dragged along by the strong gravity of the black hole to form a narrow gas stream. Credit: Keio University

    It is difficult to find black holes, because they are completely black. In some cases black holes cause effects which can be seen. For example if a black hole has a companion star, gas streaming into the black hole piles up around it and forms a disk. The disk heats up due to the enormous gravitational pull by the black hole and emits intense radiation. But if a black hole is floating alone in space, no emissions would be observable coming from it.

    A research team led by Masaya Yamada, a graduate student at Keio University, Japan, and Tomoharu Oka, a professor at Keio University, used the ASTE Telescope in Chile and the 45-m Radio Telescope at Nobeyama Radio Observatory, both operated by the National Astronomical Observatory of Japan, to observe molecular clouds around the supernova remnant W44, located 10,000 light-years away from us. Their primary goal was to examine how much energy was transferred from the supernova explosion to the surrounding molecular gas, but they happened to find signs of a hidden black hole at the edge of W44.

    NAOJ Atacama Submillimeter Telescope Experiment (ASTE)  deployed to its site on Pampa La Bola, near Cerro Chajnantor and the Llano de Chajnantor Observatory in northern Chile
    NAOJ Atacama Submillimeter Telescope Experiment (ASTE) deployed to its site on Pampa La Bola, near Cerro Chajnantor and the Llano de Chajnantor Observatory in northern Chile

    NAOJ Nobeyama Radio Observatory, located near Minamimaki, Nagano at an elevation of 1350m
    NAOJ Nobeyama Radio Observatory, located near Minamimaki, Nagano at an elevation of 1350m

    During the survey, the team found a compact molecular cloud with enigmatic motion. This cloud, named the “Bullet,” has a speed of more than 100 km/s, which exceeds the speed of sound in interstellar space by more than two orders of magnitude. In addition, this cloud, with the size of two light-years, moves backward against the rotation of the Milky Way Galaxy.

    To investigate the origin of the Bullet, the team performed intensive observations of the gas cloud with ASTE and the Nobeyama 45-m Radio Telescope. The data indicate that the Bullet seems to jump out from the edge of the W44 supernova remnant with immense kinetic energy. “Most of the Bullet has an expanding motion with a speed of 50 km/s, but the tip of the Bullet has a speed of 120 km/s,” said Yamada. “Its kinetic energy is a few tens of times larger than that injected by the W44 supernova. It seems impossible to generate such an energetic cloud under ordinary environments.”

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    Figure 3. (a) CO (J=3-2) emissions (color) and 1.4 GHz radio continuum emissions (contours) around the supernova remnant W44. (b) Galactic longitude-velocity diagram of CO (J=3-2) emissions at the galactic latitude of -0.472 degrees. (c -f): Galactic longitude-velocity diagrams of the Bullet in CO (J=1-0), CO (J=3-2), CO (J=4-3), and HCO+ (J=1-0), from left to right. Galactic longitude-velocity diagrams show the speed of the gas at a specific position. Structures elongated in the vertical direction in the diagrams have a large velocity width. Credit: Yamada et al. (Keio University), NAOJ

    The team proposed two scenarios for the formation of the Bullet. In both cases, a dark and compact gravity source, possibly a black hole, has an important role. One scenario is the “explosion model” in which an expanding gas shell of the supernova remnant passes by a static black hole. The black hole pulls the gas very close to it, giving rise to an explosion, which accelerates the gas toward us after the gas shell has passed the black hole. In this case, the astronomers estimated that the mass of the black hole would 3.5 times the solar mass or larger. The other scenario is the “irruption model” in which a high speed black hole storms through a dense gas and the gas is dragged along by the strong gravity of the black hole to form a gas stream. In this case, researchers estimated the mass of the black hole would be 36 times the solar mass or larger. With the present dataset, it is difficult for the team to distinguish which scenario is more likely.

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    Figure 4. Schematic diagrams of two scenarios for the formation mechanism of the Bullet. (a) explosion model and (b) irruption model. Both diagrams show a part of the shock front produced by the expansion of the supernova remnant W44. The shock wave enters into quiescent gas and compresses it to form dense gas. The Bullet is located in the center of the diagram and has completely different motion compared to the surrounding gas. Yamada et al. (Keio University)

    Theoretical studies have predicted that 100 million to 1 billion black holes should exist in the Milky Way, although only 60 or so have been identified through observations to date. “We found a new way of discovering stray black holes,” said Oka. The team expects to disentangle the two possible scenarios and find more solid evidence for a black hole in the Bullet with higher resolution observations using a radio interferometer, such as the Atacama Large Millimeter/submillimeter Array (ALMA).

    These observation results were published as Yamada et al. Kinematics of Ultra-high-velocity Gas in the Expanding Molecular Shell adjacent to the W44 Supernova Remnant in the Astrophysical Journal Letters in January 2017.
    The research team members are: Masaya Yamada, Tomoharu Oka, Shunya Takekawa, Yuhei Iwata, Shiho Tsujimoto, Sekito Tokuyama, Maiko Furusawa, Keisuke Tanabe, and Mariko Nomura, from Keio University, Japan.

    This research was supported by a Grant-in-Aid from the Japan Society for the Promotion of Science (No. 15H03643).

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 10:53 am on November 28, 2016 Permalink | Reply
    Tags: , , Extrasolar planet known as K2-3d may be earthlike, NAOJ   

    From NAOJ: “Potentially Habitable Extrasolar Planet Paves the Way to Search for Alien Life” 

    NAOJ

    NAOJ

    November 28, 2016
    No writer credit found

    1
    This collage summarizes the research. Using the Okayama 188-cm Reflector Telescope and the observational instrument MuSCAT (See real photo on the bottom left.), researchers succeeded in observing the extrasolar planet K2-3d, which is about the same size and temperature as the Earth, pass in front of its host star blocking some of the light coming from the star (See artistic visualization at the top.), making it appear to dim (See real data on the bottom right).

    NAOJ Okayama Astrophysical Observatory Telescope a top of Mt. Chikurin-Ji (its elevation is 372 meters) in the southwestern region of Okayama prefecture
    NAOJ okayama Astrophysical Observatory Telescope a top of Mt. Chikurin-Ji (its elevation is 372 meters) in the southwestern region of Okayama prefecture interior
    NAOJ Okayama Astrophysical Observatory Telescope a top of Mt. Chikurin-Ji (its elevation is 372 meters) in the southwestern region of Okayama prefecture.

    A group of researchers from the National Astronomical Observatory of Japan (NAOJ), the University of Tokyo, and the Astrobiology Center among others has observed the transit of a potentially Earth-like extrasolar planet known as K2-3d using the MuSCAT instrument on the Okayama Astrophysical Observatory 188-cm telescope. A transit is a phenomenon in which a planet passes in front of its parent star, blocking a small amount of light from the star, like a shadow of the planet. While transits have previously been observed for thousands of other extrasolar planets, K2-3d is important because there is a possibility that it might harbor extraterrestrial life.

    By observing its transit precisely using the next generation of telescopes, such as TMT, scientists expect to be able to search the atmosphere of the planet for molecules related to life, such as oxygen.

    TMT-Thirty Meter Telescope, proposed for Mauna Kea, Hawaii, USA
    TMT-Thirty Meter Telescope, proposed for Mauna Kea, Hawaii, USA

    With only the previous space telescope observations, however, researchers can’t calculate the orbital period of the planet precisely, which makes predicting the exact times of future transits more difficult. This research group has succeeded in measuring the orbital period of the planet with a high precision of about 18 seconds. This greatly improved the forecast accuracy for future transit times. So now researchers will know exactly when to watch for the transits using the next generation of telescopes. This research result is an important step towards the search for extraterrestrial life in the future.

    The title of the paper is Ground-based Transit Observation of the Habitable-zone Super-Earth K2-3d

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 10:47 am on September 8, 2016 Permalink | Reply
    Tags: A supercomputer recreated a blinking impossibly bright “monster pulsar.”, ATERUI Cray XC 30 supercomputer, Center for Computational Astrophysics, NAOJ   

    From NAOJ via Center for Computational Astrophysics, NAOJ: “Avoiding ‘Traffic Jam’ Creates Impossibly Bright ‘Lighthouse’ “ 

    NAOJ

    NAOJ

    1

    9.8.16
    No writer credit found

    A supercomputer recreated a blinking impossibly bright “monster pulsar.”
    The central energy source of enigmatic pulsating Ultra Luminous X-ray sources (ULX) could be a neutron star according to numerical simulations performed by a research group led by Tomohisa Kawashima at the National Astronomical Observatory of Japan (NAOJ).

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    Figure1: Artist’s impression of the “New Lighthouse Model.”(Credit: NAOJ)

    ULXs, which are remarkably bright X-ray sources, were thought to be powered by black holes. But in 2014, the X-ray space telescope “NuSTAR” detected unexpected periodic pulsed emissions in a ULX named M82 X-2.

    NASA/NuSTAR
    NASA/NuSTAR

    The discovery of this object named “ULX-pulsar” has puzzled astrophysicists. Black holes can be massive enough to provide the energy needed to create ULXs, but black holes shouldn’t be able to produce pulsed emissions. In contrast, “pulsars,” a kind of neutron star, are named for the pulsed emissions they produce, but they are much fainter than ULXs. A new theory is needed to explain “ULX-pulsar.”

    ULXs are thought to be caused by an object with strong gravity accreting gas from a companion star. As the gas falls towards the object, it collides with other gas. These collisions heat the gas until it gets hot enough to start glowing. The photons (in this case X-rays) emitted by this luminous gas are what astronomers actually observe. But as the photons travel away from the center, they push against the incoming gas, slowing the flow of gas towards the center. This force is called the radiation pressure force. As more gas falls onto the object, it becomes hotter and brighter, but if it becomes too bright the radiation pressure slows the infalling gas so much that it creates a “traffic jam.” This traffic jam limits the rate at which new gas can add additional energy to the system and prevents it from getting any brighter. This luminosity upper limit, at which the radiation pressure balances the gravitational force, is called the Eddington luminosity.

    The Eddington luminosity is determined by the mass of the object. Because pulsars have masses hundreds of thousands of times less than the black holes thought to be powering ULXs, their Eddington luminosities are much lower than what would be needed to account for bright ULXs. But Kawashima and his team started to wonder if there might be a way for pulsars to avoid the traffic jam caused by the Eddington luminosity. “The astrophysicists have been so puzzled,” he explains, “It may be difficult to sustain super-critical accretion onto neutron stars because neutron stars have solid surfaces, unlike black holes. It was a grand challenge to elucidate how to realize super-critical accretion onto neutron stars exhibiting pulsed emissions.”

    For normal pulsars, researchers use an “accretion columns” model where the infalling gas is guided by the pulsar’s strong magnetic field so that it lands on the magnetic poles. If the magnetic pole is misaligned with the neutron star’s rotation axis (much like how ‘magnetic north’ is different from ‘true north’ on Earth), then the location of the magnetic pole will revolve around the rotation axis as the neutron star spins. If the magnetic pole points towards Earth, it appears bright to us, but when it rotates away, the emissions seem to disappear. This is similar to how a lighthouse seems to blink as the direction of its beam rotates.

    In order to address the mystery of ULX-pulsar, Kawashima and his team performed simulations to see if there is some way the accretion columns of gas could flow smoothly without a traffic jam and become hundreds of times brighter than the Eddington luminosity. “No one knew if super-critical column accretion could actually be realized on a neutron star,” explains Shin Mineshige at Kyoto University, “It was a tough problem because we needed to simultaneously solve the equations of hydrodynamics and radiative transfer, which required advanced numerical techniques and computational power.” In the 1970’s, a few astrophysicists briefly addressed the calculation of moderately (not extremely) super-critical accretion columns, however they had to make many assumptions to make the calculations workable. “But thanks to recent developments in techniques and computer resources,” says Ken Ohsuga at NAOJ, “we are now at the dawn of the radiation-hydrodynamic simulations era.” The codes are already used for studies focused on black hole simulations. Thus, prompted by the discovery of ULX-pulsar, this team applied their radiation-hydrodynamic code to simulate super-critical accretion columns onto neutron stars, and carried out the simulations on the NAOJ supercomputer “ATERUI.”

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    NAOJ Cray XC30 ATERUI supercomputer

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    The new lighthouse model (a snapshot from Movie 1) and simulation results from the present research (inset on the right.) In the simulation results, the red indicates stronger radiation, and the arrows show the directions of photon flow. In this figure, many photons are produced near the surface of the neutron star and escape from the side of the accretion column. (Credit: NAOJ)

    The team found that it actually is possible for the infalling gas to avoid an Eddington luminosity induced traffic jam in super-critical column accretion. In their simulations, the accreting gas forms a shock front near the neutron star. Here, a huge amount of the kinetic energy of the infalling gas is converted to thermal energy. The gas just below the shock surface is rapidly heated by this energy and emits a huge number of photons. But rather than pushing back against the infalling gas as the previous models suggested, the photons are directed out the sides of the column. This means without a traffic jam, more gas can fall in rapidly, be heated by the shock front and produce more photons, so that the process isn’t forced to slow down.

    The NAOJ team’s model can account for the observed characteristics of ULX-pulsar: a high luminosity and directed beams of photons which will appear to blink as the neutron star rotates. Surprisingly, the direction of the photon beams is at a right angle to the polar beams expected in a standard pulsar model. This is the first simulation to support the idea that the central engine of the ULX-pulsar is a neutron star.


    Artist’s impression of the standard model of a pulsar. Photon beams are emitted from the magnetic poles of a neutron star. These photon beams twirl because of the misalignment between the magnetic poles and the rotation axis. As a result, the beams face towards an observer at regular intervals and pulsed emissions are observed coming from the neutron star. (Credit: NAOJ)


    Artist’s impression of the new cosmic lighthouse model. When gases (red) fall onto a neutron star, the accretion columns are heated by shock waves and shine brightly. Photons can escape from the columns through the sidewall and do not prevent additional gas from accreting. Therefore these columns continue to emit an enormous amount of photos. In this model, due to the misalignment between the accretion columns and the rotation axis, the appearance of the accretion columns changes periodically with the rotation of the neutron star. Dazzling pulsed emissions can be observed when the apparent area of the columns reaches maximum. (Credit: NAOJ)

    This team is planning to further develop their work by using this new lighthouse model to study the detailed observational features of the ULX-pulsar M82 X-2, and to explore other ULX-pulsar candidates.

    This research was supported in part by the Japan Society for the Promotion of Science through Grants-in-Aid for Scientific Research (No. 26400229, 15K05036)and MEXT SPIRE and JICFuS as a priority issue (Elucidation of the fundamental laws and evolution of the universe) to be tackled by using the Post K Computer.

    Their paper entitled A radiation-hydrodynamic model of accretion columns for Ultra-luminous X-ray pulsar will appear in Publications of the Astronomical Society of Japan on September 8, 2016.

    (Press Release: September 8, 2016)

    About this research

    Research Team: Tomohisa Kawashima (NAOJ), Shin Mineshige (Kyoto University), Ken Ohsuga (NAOJ), Takumi Ogawa (Kyoto University)

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 7:06 am on July 13, 2016 Permalink | Reply
    Tags: , , MIlky Way collision with Andromeda, NAOJ   

    From NAOJ: ” Galactic Merger (II. The Case of Oblique Impact)” 

    NAOJ

    NAOJ

    7.13.16
    No writer credit
    Text from Facebook entry, no link

    The Milky Way Galaxy in which we live and the neighboring Andromeda Galaxy are currently being drawn together through their mutual gravity. It is thought that they will collide in approximately another 4 billion years.

    NAOJ Milky Way merger with Andromeda
    NAOJ Milky Way merger with Andromeda

    This kind of collision between galaxies has actually been observed many times in the Universe. So what happens when galaxies collide? This video is a visualization of simulations performed with a supercomputer for the case of two spiral galaxies colliding obliquely.

    Formation of Giant Star Clusters Resulting from a Galactic Collision

    It’s called a galactic “collision,” but the individual stars within the galaxies don’t collide; they pass each other within the galaxies. But the gas filling the galaxies is compressed into strips where the galaxies collide, and clumps of thick gas form in these regions. Stars form explosively within these gas clouds, and these stars collect to create giant star clusters. Then the two galaxies move past each other, dragging along the star clusters formed by the collision.

    But before long, the two galaxies are pulled back towards each other by their mutual gravity and collide again. And finally they become a single large galaxy. Around the galaxy formed by this merger there are large star clusters which were formed in the first collision. From this simulation we learned that galactic mergers form a far larger mass of star clusters than previously thought.

    http://www.nao.ac.jp/en/gallery/weekly/2016/20160712-4d2u.html

    (YouTube)

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array
    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 11:54 am on March 3, 2016 Permalink | Reply
    Tags: , , Fraunhofer lines of the sun, NAOJ,   

    From NAOJ: “Fraunhofer Lines of the Sun” 

    NAOJ

    NAOJ

    Universe of Spectroscopy

    November 16, 2011 [Presented by NAOJ March 3, 2016]
    Yukio Katsukawa

    Fraunhofer Lines of the Sun Norikura Solar Observatory
    Solar spectra observed by 25cm Cornagraph at Norikura Solar Observatory. The Fraunhofer lines (C, D, E, F, G, H,and K lines) are indicated.

    When you let sunlight pass through a prism, you can see that the light is broken up into the colors of the rainbow (a spectrum). If you observe the spectrum more carefully, you will find countless dark features. These are absorption lines caused by impurities such as calcium, sodium, magnesium, iron, and so on. The chief element of the Sun is hydrogen, and the impurities in minuscule quantities absorb the light coming from the inside at specific wavelengths, resulting in the dark features.

    The Fraunhofer lines are a set of famous absorption lines named after a German physicist. Fraunhofer designated the principal features with the letters A through K from longer wavelength (redder) to shorter (bluer). For example, the D line is caused by sodium, and the H and K lines are caused by calcium. Some Fraunhofer lines were known to originate in absorption in the Earth’s atmosphere.

    The Fraunhofer lines are, indeed, a lifeline of solar physicists. The depths of the absorption lines provide information about temperature, and the wavelength shifts of the lines tell us the motion of gas. If the Sun consisted only of pure hydrogen, there would be no absorption line. This would mean that the researchers could not study the temperature or the motion of the Sun’s atmosphere. This would be the end for them. Thanks to the impurities, we can investigate the Sun in detail.

    3-D Structure of the Sun’s atmosphere

    A dark feature in a spectrum results from absorption of light at a given wavelength. This means a low degree of transparency of the atmosphere at this wavelength. Therefore, we can only observe the outer region of the Sun at this wavelength. We utilize this to study the atmosphere outside the region where we usually observe. The degree of the transparency of the Sun’s atmosphere depends on the absorption lines. Thus, we combine several absorption lines to observe several layers and to study the 3D structure of the Sun’s atmosphere.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 7:51 am on February 23, 2016 Permalink | Reply
    Tags: , , , Dark Matter Halo, NAOJ   

    From NAOJ: “Formation and Evolution of Dark Matter Halos (II. Formation of the Large-Scale Structure of the Universe) 

    NAOJ

    NAOJ

    Dark matter halo
    Visualization of Dark Matter Halo.ESA

    This video is a visualization of the evolution of dark matter distribution from the beginning of the Universe up to the present. Right after the birth of the Universe, dark matter is distributed almost uniformly. But parts with slightly higher densities gravitationally attract the surrounding dark matter to form small halos. Through mergers, these small halos evolve into larger haloes. Within these larger halos gas collects and galaxies form. Furthermore, galaxies group together to form galaxy clusters connected by galaxies distributed in a framework pattern. This is known as the large-scale structure of the Universe.


    Download mp4 video here .

    Exploring the History of Structure Formation in the Universe through Large-Scale Simulations

    In this simulation, the dark matter density distribution at the beginning of the Universe is represented by approximately 8.6 billion particles. The evolution of dark matter halos through mutual gravitational interaction is followed up to the present. By calculating the evolution of the (baryonic) matter, which is the material for stars and galaxies, based on the dark matter distribution obtained through these calculations, it has become possible to predict the distribution, evolution, and statistical characteristics of things like galaxies or active galactic nuclei over a wider area than ever before. Simulation results obtained in this manner can be used as a database to compare with wide field observations performed in the future by facilities like the Subaru Telescope.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 7:36 pm on January 15, 2016 Permalink | Reply
    Tags: , , Intermediate mass black holes, NAOJ   

    From NAOJ: “Signs of Second Largest Black Hole in the Milky Way – Possible Missing Link in Black Hole Evolution” 

    NAOJ

    NAOJ

    January 15, 2016
    No writer credit found

    Temp 1
    Artist’s impression of the clouds scattered by an intermediate mass black hole.

    Astronomers using the Nobeyama 45-m Radio Telescope have detected signs of an invisible black hole with a mass of 100 thousand times the mass of the Sun around the center of the Milky Way. The team assumes that this possible “intermediate mass” black hole is a key to understanding the birth of the supermassive black holes located in the centers of galaxies.

    NAOJ Nobeyama 45m Radio Telescope
    Nobeyama 45-m Radio Telescope

    A team of astronomers led by Tomoharu Oka, a professor at Keio University in Japan, has found an enigmatic gas cloud, called CO-0.40-0.22, only 200 light years away from the center of the Milky Way. What makes CO-0.40-0.22 unusual is its surprisingly wide velocity dispersion: the cloud contains gas with a very wide range of speeds. The team found this mysterious feature with two radio telescopes, the Nobeyama 45-m Telescope in Japan and the ASTE Telescope in Chile, both operated by the National Astronomical Observatory of Japan.

    ASTE Atacama Submillimeter telescope
    ASTE telescope

    Temp 2
    Figure. (a) The center of the Milky Way seen in the 115 and 346 GHz emission lines of carbon monoxide (CO). The white regions show the condensation of dense, warm gas. (b) Close-up intensity map around CO-0.40-0.22 seen in the 355 GHz emission line of HCN molecules. The ellipses indicate shell structures in the gas near C0-0.40-0.22. (c) Velocity dispersion diagram taken along the dotted line shown above. The wide velocity dispersion of 100 km/s in CO-0.40-0.22 stands out.

    To investigate the detailed structure, the team observed CO-0.40-0.22 with the Nobeyama 45-m Telescope again to obtain 21 emission lines from 18 molecules. The results show that the cloud has an elliptical shape and consists of two components: a compact but low density component with a very wide velocity dispersion of 100 km/s, and a dense component extending 10 light years with a narrow velocity dispersion.

    What makes this velocity dispersion so wide? There are no holes inside of the cloud. Also, X-ray and infrared observations did not find any compact objects. These features indicate that the velocity dispersion is not caused by a local energy input, such as supernova explosions.

    The team performed a simple simulation of gas clouds flung by a strong gravity source. In the simulation, the gas clouds are first attracted by the source and their speeds increase as they approach it, reaching maximum at the closest point to the object. After that the clouds continue past the object and their speeds decrease. The team found that a model using a gravity source with 100 thousand times the mass of the Sun inside an area with a radius of 0.3 light years provided the best fit to the observed data. “Considering the fact that no compact objects are seen in X-ray or infrared observations,” Oka, the lead author of the paper that appeared in the Astrophysical Journal Letters, explains “as far as we know, the best candidate for the compact massive object is a black hole.”

    If that is the case, this is the first detection of an intermediate mass black hole. Astronomers already know about two sizes of black holes: stellar-mass black holes, formed after the gigantic explosions of very massive stars; and supermassive black holes (SMBH) often found at the centers of galaxies. The mass of SMBH ranges from several million to billions of times the mass of the Sun. A number of SMBHs have been found, but no one knows how the SMBHs are formed. One idea is that they are formed from mergers of many intermediate mass black holes. But this raises a problem because so far no firm observational evidence for intermediate mass black holes has been found. If the cloud CO-0.40-0.22, located only 200 light years away from Sgr A* (the 400 million solar mass SMBH at the center of the Milky Way), contains an intermediate mass black hole, it might support the intermediate mass black hole merger scenario of SMBH evolution.

    Temp 3
    Sagittarius A*. This image was taken with NASA’s Chandra X-Ray Observatory. Ellipses indicate light echoes. source
    Date 23 July 2014

    NASA Chandra Telescope
    NASA/Chandra

    Temp 4
    (Top) CO-0.40-0.22 seen in the 87 GHz emission line of SiO molecules. (Bottom) Position-velocity diagram of CO-0.04-0.22 along the magenta line in the top panel.

    Temp 5
    (Top) Simulation results for two moving clouds affected by a strong compact gravity source. The diagram shows changes in the positions and shapes of the clouds over a period of 900 thousand years (starting from t=0) at intervals of 100 thousand years. The axes are in parsecs (1 parsec = 3.26 light years). (Bottom) Comparison of observational results (in gray) and the simulation (red, magenta, and orange) in terms of the shape and velocity structure. The shapes and velocities of the clouds at 700 thousand years in the simulation match the observational results well.

    These results open a new way to search for black holes with radio telescopes. Recent observations have revealed that there are a number of wide-velocity-dispersion compact clouds similar to CO-0.40-0.22. The team proposes that some of those clouds might contain black holes. A study suggested that there are 100 million black holes in the Milky Way Galaxy, but X-ray observations have only found dozens so far. Most of the black holes may be “dark” and very difficult to see directly at any wavelength. “Investigations of gas motion with radio telescopes may provide a complementary way to search for dark black holes” said Oka. “The on-going wide area survey observations of the Milky Way with the Nobeyama 45-m Telescope and high-resolution observations of nearby galaxies using the Atacama Large Millimeter/submillimeter Array (ALMA) have the potential to increase the number of black hole candidates dramatically.”

    ALMA Array
    ALMA

    The observation results were published as Oka et al. “Signature of an Intermediate-Mass Black Hole in the Central Molecular Zone of Our Galaxy” in the Astrophysical Journal Letters issued on January 1, 2016. The research team members are Tomoharu Oka, Reiko Mizuno, Kodai Miura, Shunya Takekawa, all at Keio University.

    This research is supported by the Japanese Society for the Promotion of Science (JSPS) Grant-in-Aid for Scientific Research (C) No. 24540236.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 2:21 pm on November 16, 2015 Permalink | Reply
    Tags: , , , NAOJ   

    From NAOJ: “KAGRA’s Initial Operation To Begin Soon” 

    NAOJ

    NAOJ

    November 16, 2015

    The Large-Scale Gravitational Wave Telescope, KAGRA, in Kamioka, Japan, whose aim is to perform the world’s first direct detection of gravitational waves, will soon commence operation.

    KAGRA is a next-generation telescope currently under construction in Kamioka, which is also home to Super-Kamiokande and other observational facilities well-known for their world-leading research in fundamental physics. Unlike the ordinary optical telescopes that look up the night sky at high altitudes or through space affected by less air turbulence, such as the Subaru Telescope and Hubble Space Telescope, KAGRA observes the universe from underground. The direct detection of gravitational waves, as we discuss below, requires such an unconventional method.

    What Gravitational Waves Can Tell Us

    Gravitational wave emission is one of the predictions made by the Einstein’s General Theory of Relativity. The indirect proof of its existence was given in 1979 when Dr. Hulse and Dr. Taylor observed the orbit of a binary pulsar, which was affected by loss of energy due to gravitational waves. However, the direct detection of gravitational waves has yet to come.

    Since the dawn of human history, we have understood the world as observed using light. In the past 200 years, observations using other parts of the electromagnetic spectrum–the microwave, infrared, ultra-violet, X-ray, and gamma rays–have expanded the horizon of our knowledge of the nature, vastly enriching our life. Now with the addition of a new observational media, the gravitational wave, it is anticipated that phenomena in our universe undetectable with electromagnetic waves–such as the beginning of the universe and the birth of black holes–may become “visible”.

    1
    An artist’s impression of gravitational waves from a neutron star binary (Credit: KAGAYA)

    How To Detect Gravitational Waves

    Gravitational waves affect the distance between two points in space-time, stretching and shrinking the space between two objects at the frequency of the gravitational wave. Gravitational wave telescopes detect these changes of distance. However, the typical undulation of space due to gravitational waves is no more than of the order of the size of a hydrogen atom (about 0.1 nanometers) change in the distance between the Sun and the Earth (about 150 million kilometers). To detect such small ripples on the space, a telescope with 3-km arms must be sensitive to the change in a trillionth of 100 millionth of a meter. Recent technological developments across the globe have enabled us to build telescopes sensitive to about three to ten times the distance displaced by typical gravitational waves. Several large-sized gravitational wave telescopes are currently under construction worldwide, each aiming for the target detection sensitivity.

    2
    KAGRA Project (Image: ICRR)

    How Researchers Collaborate To Achieve KAGRA’s Detection Sensitivity

    Because the expected signals from the gravitational waves are very small, researchers must eliminate all possible sources of background noise that affect the telescope. Among others, the two largest sources are seismic noise and thermal noise. The KAGRA group, which is lead by ICRR, incorporates KEK and NAOJ to maneuver its technological R&D to reduce the various noises as much as possible.

    For instance, ICRR researchers chose the underground of Mt. Ikenoyama in Kamioka as the construction site for KAGRA to minimize the seismic noises, and excavated a new 7km-long tunnel 200m underground near the Kamioka mine. The seismic amplitudes in the tunnel measures a hundredth that of the ground surface, an essential requirement for stable operation of the telescope. KAGRA has two 3km arms extending at a right angle, which meant that the team had to excavate a tunnel the length of 7,700m including the access tunnel. The team completed the operation successfully in just 1 year and 10 months.

    Setting the telescope underground takes out most of the seismic noise; however, there are still large enough noises that can affect essential components of the telescope such as mirrors placed at the ends of each arm reflecting laser beams back and forth. The NAOJ team contributed in developing the enhanced anti-vibration system owing to their vast experience with the previous gravitational wave detector, TAMA300, which was built at their site in Mitaka, Tokyo. The team has successfully developed equipment to protect mirrors from vibrations utilizing extremely precise pendula and springs with special materials. TAMA300 previously held the world record for detection sensitivity, and the continuous runtime of more than 1,000 hours.

    Furthermore, KEK’s team contributed another aspect of the noise reduction. The mirrors, which are the heart of the telescope, have generic thermal noises due to their own temperature. Making full use of their knowledge and experience in the area of cryogenics, the team developed cryostats that cool the mirrors and keep them at -253°C.

    These are examples of our collaborative efforts for enhanced sensitivity between three leading institutions of the KAGRA group; however, the gravitational wave telescope requires many other high-performing detector components to come together to operate as a full functioning telescope. Researchers from home and abroad have worked on such components as the vacuum system, the laser source, the auxiliary optics, the detector control system, the data acquisition system, and the data analysis methods.
    When KAGRA Will Detect Gravitational Waves

    The excavation of the KAGRA tunnel was completed in March 2014. The group then proceeded to install/develop the laser source, the vacuum pipes, the cryostats and other equipment, and completed most of the installations that are needed to commission the initial KAGRA operation.

    The test run will start within 2015 JFY, after the final adjustments. The full operation of KAGRA is planed to start in 2017 JFY, when the team aims for the world’s first direct detection of gravitational waves.

    4
    KAGRA’s vacuum pipes (Credit: ICRR)

    Gravitational Wave Astronomy As A New Discipline

    Many countries worldwide are engaged in competition in pursuit of detecting the gravitational waves before others. The US group constructed two gravitational wave telescopes called LIGO, with two 4-km arms each, and is now closing in on the target detector sensitivity. A European collaboration mainly formed by Italy, France, and the Netherlands, also constructed a gravitational wave telescope called VIRGO, and now is developing the advanced version of the detector.

    Caltech Ligo
    MIT/Caltech Advanced LIGO

    VIRGO Gravitational Wave interferometer
    VIRGO

    The teams of the gravitational wave telescopes in these three regions of the globe, however, not only compete but also depend on one another. A single telescope will not be sufficient to claim the first detection of the gravitational wave, which requires confirmation by others. In the near future a global network of gravitational wave telescopes may bring about an entirely new discipline–Gravitational Wave Astronomy.

    5
    A global network of gravitational wave telescopes (Credit: ICRR)

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
  • richardmitnick 5:43 am on October 20, 2015 Permalink | Reply
    Tags: , , NAOJ, Solar Tower Telescope   

    From NAOJ: “Solar Tower Telescope Coelostat” 

    NAOJ

    NAOJ

    October 20, 2015

    1

    The Solar Tower Telescope (nicknamed the Einstein Tower) was commissioned in 1928. It is one of the foundation telescopes prepared around the time that the Tokyo Astronomical Observatory relocated from Mafu to Mitaka in September of 1924. The coelostat in this picture was manufactured by Carl Zeiss Optical Works in Germany. This telescope played a pivotal role in spectroscopic observations of Sun until the mid-1960s, leading Japanese astrophysics. After this role was completed, it lay dormant for a long time. But thanks to the Archive Office, dome restoration and drive system repair were conducted. This is the appearance of the equipment after it was renovated in 2013.

    2

    The Evolution of the Solar Tower Telescope

    The Solar Tower Telescope uses the coelostat installed in the fifth story rooftop dome to steer light into the tower itself which acts as the body of the telescope. At first, the coelostat had two German 60-cm-aperture glass plane mirrors made by Carl Zeiss Optical Works; but from 1953 to 1957 it was renovated with fused silica plane mirrors having a low thermal expansion coefficient produced by Nippon Kougaku*. Additionally, the refractive telescope was replaced with a 48-cm-diameter chromatic-aberration-free Cassegrain reflector telescope with an effective focal length of 22 m, also produced by Nippon Kougaku.

    The major scientific achievements include studying the profile of a magnesium triplet spectral line, measuring the rotation of the Sun through the Doppler Effect, studying the Zeeman Effect in sunspots, and research on the atomic spectra of sunspots.

    Restoration proceeded in the hands of the Archive Office which was established in 2008. Dome restoration was conducted in 2012; telescope drive system repair was carried out; an image of the Sun was formed at the focus; and now a spectrum formed by the prism spectrograph can be seen. The Solar Tower Telescope building was designated a registered tangible cultural property of Japan in 1998.
    Solar Spectrum seen at the Solar Tower Telescope

    The Solar Tower Telescope has had its dome and drive system repaired, and is now able to successfully form an image of the Sun on the spectrograph slit. It can observe the Sun’s spectrum via the spectrograph equipped with three large prisms. On Mitaka Open House Day, October 23 & 24, 2015, please come and see the Solar Tower Telescope which has been restored to how it was almost 50 years ago.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition
    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

    NAOJ Subaru Telescope interior
    Subaru

    ALMA Array
    ALMA

    sft
    Solar Flare Telescope

    Nobeyama Radio Telescope - Copy
    Nobeyama Radio Observatory

    Nobeyama Solar Radio Telescope Array
    Nobeyama Radio Observatory: Solar

    Misuzawa Station Japan
    Mizusawa VERA Observatory

    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
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