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  1. No Access

    Article

    Earth encounters as the origin of fresh surfaces on near-Earth asteroids

    The 'ordinary chondrite problem' has been a factor in Solar System astronomy for three decades. It refers to the apparent anomaly that whereas about 80% of the meteorites falling to Earth are 'ordinary chondri...

    Richard P. Binzel, Alessandro Morbidelli, Sihane Merouane, Francesca E. DeMeo… in Nature (2010)

  2. No Access

    Article

    Semi-annual oscillations in Saturn’s low-latitude stratospheric temperatures

    Both Earth and Jupiter have equatorial oscillations in their atmospheres, with two-year and four-year periodicity respectively. Two groups working independently now report a related phenomenon on Saturn. Orton et...

    Glenn S. Orton, Padma A. Yanamandra-Fisher, Brendan M. Fisher, A. James Friedson… in Nature (2008)

  3. No Access

    Chapter

    Carbonaceous Onion-Like Particles: A Possible Component of the Interstellar Medium

    A carbonaceous material formed from a hydrocarbon plasma called quenched carbonaceous composite (QCC) is shown to have functional groups that approximate the positions of the interstellar 217.5 nm absorption a...

    Setsuko Wada, Alan T. Tokunaga in Natural Fullerenes and Related Structures … (2006)

  4. No Access

    Chapter and Conference Paper

    Near-Infrared AO Spectroscopy of Edge-On Protoplanetary Disks with Subaru IRCS

    We carried out near infrared (1.4–4.2 μm) AO imaging and spectroscopy of two edge-on protoplanetary disks; HK TauB and HV TauC located in Taurus molecular cloud. We found a deep H2O Ice absorption (τ~ 1.1, 1.3) f...

    Hiroshi Terada, Naoto Kobayashi, Alan T. Tokunaga… in Science with Adaptive Optics (2005)

  5. No Access

    Chapter and Conference Paper

    The Structure of the Young Stellar Outflows Revealed by High Angular Resolution [Fe II] λ 1.644 μ m Spectroscopy

    We introduce results of the [Fe ii] λ1.644 μm spectroscopic observations toward the outflows emanating from L1551 IRS 5, DG Tau, HL Tau, and RW Aur. We resolved the region within ~±140 AU (< ±1′′) from their driv...

    Tae-Soo Pyo, Masahiko Hayashi, Naoto Kobayashi… in Science with Adaptive Optics (2005)

  6. No Access

    Article

    The Structure of Young Stellar Jets and Winds Revealed by High Resolution [Fe II] λ1.644μm Line Observations

    We present high angular resolution spectra taken along the jets from L1551 IRS 5 and DG Tau obtained with the Subaru Telescope. The position-velocity diagrams of the [Fe II] λ 1.644 μmemission line revealed re...

    Tae-Soo Pyo, Masahiko Hayashi, Naoto Kobayashi… in Astrophysics and Space Science (2003)

  7. No Access

    Chapter

    Detection of Extended Water Vapor Atmosphere of Mira by Near-Infrared Spectroimagery

    We present the first spectroimagery of extended molecular atmosphere of Mira spatially resolved by adaptive optics system. We found the molecular atmosphere of H2O, CO and CO2 is extended to about 40 mas. The pre...

    Hideki Takami, Miwa Goto, Wolfgang Gaessler… in Mass-Losing Pulsating Stars and their Circ… (2003)

  8. No Access

    Chapter

    The Structure of Young Stellar Jets and Winds Revealed By High Resolution [Fe Ii] λL.644μM Line Observations

    We present high angular resolution spectra taken along the jets from L1551 IRS 5 and DG Tau obtained with the Subaru Telescope. The position-velocity diagrams of the [Fe II] λ 1.644 μm emission line revealed r...

    Tae-Soo Pyo, Masahiko Hayashi, Naoto Kobayashi… in Jets in Young Stellar Objects (2003)

  9. No Access

    Chapter

    Infrared Spectroscopy of Disks Around Young Stellar Objects

    Accretion disks are considered to be central to the formation of stars and planetary systems. While the evidence for disks around young stars is compelling, it is largely indirect, and most disk properties are...

    John S. Carr, Alan T. Tokunaga, Joan Najita… in Infrared Astronomy with Arrays (1994)

  10. No Access

    Chapter

    Infrared Techniques for Comet Observations

    The infrared spectral region (1–1000 µm) is important for studies of both molecules and solid grains in comets. Infrared astronomy is in the midst of a technological revolution, with the development of sensitive ...

    Martha S. Hanner, Alan T. Tokunaga in Comets in the Post-Halley Era (1991)

  11. No Access

    Chapter and Conference Paper

    Bright Near-Infrared Sources Within 1° of the Galactic Center

    A near-infrared survey has been conducted of 0.55 square degrees around the Galactic center with the 1 m telescope of Siding Spring Observatory, Australia. From the detected sources, 39 objects which are brigh...

    Tetsuya Nagata, Shuji Sato, A. R. Hyland, Alan T. Tokunaga in The Center of the Galaxy (1989)

  12. No Access

    Chapter

    A Faint Object Spectrometer for the Infrared

    A cryogenic astronomical spectrometer for the NASA Infrared Telescope Facility is described. This spectrometer will employ an array of at least 20 detectors and provide a resolving power of 100 to 1500 at 1–5 ...

    Alan T. Tokunaga, Robert G. Smith in Third Asian-Pacific Regional Meeting of th… (1986)

  13. No Access

    Article

    A faint object spectrometer for the infrared

    A cryogenic astronomical spectrometer for the NASA Infrared Telescope Facility is described. This spectrometer will employ an array of at least 20 detectors and provide a resolving power of 100 to 1500 at 1–5 ...

    Alan T. Tokunaga, Robert G. Smith in Astrophysics and Space Science (1986)

  14. No Access

    Article

    The 20-µm brightness temperature of the unilluminated side of Saturn's rings

    The 20-µm brightness temperature of the unilluminated (north) side of Saturn's rings is reported here to be 56±1 K. This measurement, together with previous measurements of the rings at 20 µm, shows that the b...

    Alan T. Tokunaga, John Caldwell, Ira G. Nolt in Nature (1980)