Press Release

Astronomers have found clear indications that clumps of dark matter are the nursing grounds for new born galaxies about twelve billion light years away. A single nest of dark matter can nurture several young galaxies. These results from researchers at the Space Telescope Science Institute, the National Astronomical Observatory of Japan, and the University of Tokyo confirm predictions of the currently dominant theory of cosmology known as the cold dark matter model.

Subaru Telescope, using Suprime-Cam, took the clearest most complete image to date of the spiral galaxy NGC 2403. At a distance of 10 million light years, NGC 2403 is an Sc type galaxy, which has open spiral arms and a small nucleus. It is approximately half the mass of our own galaxy, the Milky Way, and has an abundance of neutral hydrogen gas. In the spiral arms we see active star formation regions in red, clusters of young blue stars called OB associations, and darker regions called dust lanes where light is blocked by gas and dust within the galaxy.

Coordinated observations of the collision of NASA's Deep Impact mission with comet 9P/Tempel 1 by the Subaru, Gemini and Keck telescopes on Mauna Kea delivered surprising new insights into the ancestry and life-cycles of comets. Specifically, materials beneath the comet’s dusty skin shows striking similarities between two families of comets where no relationship had been suspected.

Four billion years ago, the solar system went through an epoch of collisions that left craters throughout the inner solar system, including Earth, the Moon and other rocky bodies. A study by astronomers from the University of Arizona and the National Astronomical Observatory of the Japan shows that the size distribution of objects in the asteroid belt match the size distribution of these craters for sizes ranging from a few hundred meters to tens of kilometers. Subaru contributed to the measurement of the size distribution of asteroids, and NAOJ's simulation computers calculated the size of objects that created the craters.

Subaru succeeded in obtaining a precise distance to the most distant cosmic explosion ever seen. Such cosmic explosions, called gamma-ray bursts, are thought to occur when a massive star collapses and creates a black hole. Observations by Subaru and other telescopes on Mauna Kea, Hawaii, were instrumental in showing that this explosion is 500 million light-years more distant than all previously known explosions of its kind. The distance of the explosion, 12.8 billion light-years away, is at the observational frontier of space.

An international group of astronomers has used the Coronagraphic Imager for Adaptive Optics (CIAO) on the Subaru telescope in Hawai'i to obtain very sharp near-infrared polarized-light images of the birthplace of a massive proto-star known as the Becklin-Neugebauer (BN) object at a distance of 1500 light years from the Sun (Note 1). The group's images led to the discovery of a disk surrounding this newly forming star. This finding, described in detail in the September 1 issue of Nature, deepens our understanding of how massive stars form.

The integral field spectra of the galaxy NGC 1052, obtained by researchers at Kyoto University and the National Astronomical Observatory of Japan by using a guest instrument Kyoto 3DII, have revealed a high velocity bipolar outflow and its detailed structures. These will provide constraints on models for origins of gas outflows associated with central supermassive black holes, particularly because the active galactic nucleus of NGC 1052 is young. Gas outflows are considered to have affected the evolution of galaxies since the early phase of the universe.

(Japanese Only)

(Japanese Only)

Scientists at the University of Tokyo, University of Kyoto, National Astronomical Observatory of Japan, and the University of Hawaii teamed up to obtain the deepest infrared image of an almost empty field in the sky. Using Subaru's Adaptive Optics system (AO) and Infrared Camera and Spectrograph (IRCS), they observed the "Subaru Deep Field", an area of the sky well suited for studying the origin and evolution of galaxies. They achieved twice the sensitivity of previous observations at the infrared wavelength of 2.12 micrometers. Thanks to AO technology, the spatial resolution of their data is better than Hubble Space Telescope's at this wavelength, clearly revealing the shapes of distant galaxies.

(Japanese Only)

(Japanese Only)

The National Astronomical Observatory of Japan (NAOJ) and the Institute of Physical and Chemical Research (RIKEN) have successfully developed an all solid-state laser to produce an "artificial star" in the upper atmosphere to expand operation of the Subaru telescope's adaptive optics system. An adaptive optics system has been in operation at the Cassegrain focus of the Subaru telescope providing high-resolution images by compensating for atmospheric turbulence since December, 2000.

A collaboration of astronomers from Japan, USA, and Chile have discovered an unusual extra-solar planet whose properties favors a formation process of gaseous planets to start from a solid core and accumulate gaseous material. However its excessive weight created another mystery to solve. The Subaru and Keck telescopes on Mauna Kea, Hawaii, contributed to this discovery.

Kenichi Nomoto, Nobuyuki Iwamoto and other researchers from the University of Tokyo and the Japan Atomic Energy Research Institute have found new evidence that two stars that were thought to be among the earliest generations of stars were in fact formed from the explosion of older stars. Their new computer simulations of the life and death of first generation stars and the chemical elements they produce match earlier observational data from Subaru telescope.

(Japanese Only)

(Japanese Only)

An international research team, led by astronomers from the University of Tokyo, Hiroshima University, and the National Astronomical Observatory of Japan, used the Subaru telescope to obtain the spectrum of SN2003jd, a hypernova unaccompanied by a gamma-ray burst, and found the first evidence that it is a jet-like explosion viewed off-axis. Hypernovae are hyper-energetic supernovas that are often associated with gamma-ray bursts. This result provides clear and firm evidence that all hypernovae may be associated with gamma-ray bursts, but that gamma-ray bursts are observable only when jets produced by the hypernova explosion point towards Earth.

A detailed survey of the outer planets by David Jewitt, from the University of Hawaii, and colleagues have netted twelve new moons for Saturn. This brings the total number of moons for the large outer plants to 63 for Jupiter, 46 for Saturn, 27 for Uranus, 13 for Neptune and 1 for Pluto. The new moons are small and irregular, probably only 3 to 7 km in size. They are more like asteroids than Earth's moon, and may have even originated in the asteroid belt between Mars and Jupiter, although their origin remains a mystery. The moons were discovered using the Subaru telescope and confirmed using the Gemini North telescope, also on Mauna Kea.

Detailed new images of the starbirth nursery in the Omega Nebula (M17) have revealed a multi component structure in the envelope of dust and gas surrounding a very young star. The stellar newborn, called M17-SO1, has a flaring torus of gas and dust, and thin conical shells of material above and below the torus.

An international team of astronomers reports the discovery of a star, HE1327-2326, which sets a new record for being the most heavy element-deficient star ever found. Its chemical composition, as measured with the Subaru Telescope High Dispersion Spectrograph, provides evidence of nucleosynthesis by the first generations of stars in the universe, and places new constraints on their masses and metal enrichment history in the very early universe.

A search for transient phenomena in galaxies using the Subaru telescope by a research group led by Dr. Tomonori Totani at Kyoto University has led to the discovery of visible flares in the centers of apparently normal galaxies. The galaxies showing a rapid increase in visible brightness in their centers are about 4 billion light years away, and the increase in brightness occurred over just a few days. This light is probably coming from disks of hot matter rotating close to the speed of light, about 1 billion kilometers from supermassive black holes about 100 million times heavier than the Sun. These black holes are much heavier than the black hole at the center of the Milky Way, which is about 3 million times more massive than the Sun. This is the first time that such violent activity is observed from such heavy black holes in visible light. The fact that the flares are occurring in otherwise normal looking galaxies support the idea that black holes exist in the center of almost all galaxies.

Scientists at the NASA Goddard Space Flight Center and the University of Tokyo peered through the thick gas and dust of a stellar birthplace in the RCoronae Australis star forming cloud using the XMM-Newton X-ray Telescope, to find a superhot plasma of 40 mega-kelvin on a deeply embedded mysterious object. Followup infrared observations with the Subaru telescope identified the X-ray source as one of the youngest stars ever observed. Magnetic activity coupled with the infall of matter onto the still-growing star may produce the X-ray emission.

Astronomers have weighed DH Tauri's companion and have found that it is a brown dwarf with only 40 times the mass of Jupiter. DH Tauri is a young star only one million years old in the constellation Taurus. It is so young it will not begin nuclear fusion for another one hundred million years. It is 460 light years away and two thirds as massive as the Sun. It's companion is among the coolest and lightest of known brown dwarfs orbiting young stars. If the companion had been less massive it probably would have been a planet.

Only one billion years after the Big Bang, clusters of galaxies were already forming. This discovery pushes back the age of the youngest known galaxy cluster by a third, and shows that the largest astronomical objects in the Universe had already begun to form in one of the earliest epochs of the Universe that astronomers have been able to observe. This work was conducted by researchers from the University of Tokyo, the National Astronomical Observatory of Japan, and elsewhere using the Subaru telescope.

David Jewitt (University of Hawaii) and Jane Luu (MIT Lincoln Lab) have obtained the first high quality spectrum of Quaoar using the Subaru telescope. Quaoar is a bright object in the Kuiper Belt, the repository of the Solar System's most primitive building blocks beyond the orbit of the planet Neptune. The spectrum shows evidence for crystalline water ice which has an approximate lifetime of 10 million years on Quaoar's surface. This suggests that some process is still active, 4500 million years after the formation of the Solar System, either excavating Quaoar's surface to reveal crystalline water ice formed in the past, or heating it to create new crystalline water ice. While the interpretation remains speculative, the good news is that astronomers are, for the first time, able to take useful spectra that reveal unexpected and intriguing properties of the surface of distant Quaoar.