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Dense gas and cold dust in the dark core B217
Lemke, D.; Walmsley, C. M.; Harju, J. +2 more
The Barnard object B217 was observed in the infrared and radio region. The 170 mu m continuum was detected with ISOPHOT, the ammonia 1.3 cm radio lines with the Effelsberg 100 m-telescope. Mapping B217SW in (J,K)=(1,1) and (2,2) inversion lines revealed the temperature and density distribution of the gas and made it possible to investigate the dyn…
Arp 220: A Circumnuclear Polar Ring as an Alternative to a Double Nucleus?
Eckart, A.; Downes, D.
Recent millimeter interferometer observations of Arp 220 have yielded ~0.5" resolution images showing two strong concentrations of millimeter radio continuum and CO line emission embedded in a larger molecular gas disk (r~1 kpc). The interferometer observations also revealed a complex velocity field with steep velocity gradients across each of the…
Coordinated Cluster, ground-based instrumentation and low-altitude satellite observations of transient poleward-moving events in the ionosphere and in the tail lobe
Pitout, F.; Balogh, A.; Wild, J. A. +35 more
During the interval between 8:00-9:30 on 14 January 2001, the four Cluster spacecraft were moving from the central magnetospheric lobe, through the dusk sector mantle, on their way towards intersecting the magnetopause near 15:00 MLT and 15:00 UT. Throughout this interval, the EISCAT Svalbard Radar (ESR) at Longyearbyen observed a series of polewa…
Diameters of δ Cephei and η Aquilae Measured with the Navy Prototype Optical Interferometer
Hajian, Arsen R.; Hummel, C. A.; Germain, M. E. +5 more
We have measured the diameters of the Cepheid variables δ Cephei (18 nights) and η Aquilae (11 nights) with the Navy Prototype Optical Interferometer. The primary results of these observations are the mean angular diameters <θLD> of these Cepheids: 1.520+/-0.014 milliseconds of arc (mas) for δ Cep and 1.69+/-0.04 mas for η Aql. We…
Ultraviolet Signposts of Resonant Dynamics in the Starburst-ringed SAB Galaxy M94 (NGC 4736)
Madore, Barry F.; Keel, William C.; O'Connell, Robert W. +10 more
The dynamic orchestration of star-birth activity in the starburst-ringed galaxy M94 (NGC 4736) is investigated using images from the Ultraviolet Imaging Telescope (UIT; far-ultraviolet [FUV] band), Hubble Space Telescope (HST; near-ultraviolet [NUV] band), Kitt Peak 0.9 m telescope (Hα, R, and I bands), and Palomar 5 m telescope (B band), along wi…
Cluster EDI convection measurements across the high-latitude plasma sheet boundary at midnight
Baumjohann, W.; Torbert, R. B.; Matsui, H. +15 more
We examine two crossings of three Cluster satellites from the polar cap into the high-latitude plasma sheet at midnight local time, using data from the Electron Drift Instrument (EDI). EDI measures the full electron drift velocity in the plane perpendicular to the magnetic field for any field and drift directions. The context of the measured conve…
The heliosphere after Ulysses
Marsden, R. G.
Launched in October 1990, the ESA-NASA Ulysses mission has conducted the very first survey of the heliosphere within 5 AU of the Sun over the full range of heliolatitudes. With polar passes taking place in 1994 and 1995, the timing of the mission has enabled Ulysses to characterise the global structure of the heliosphere at solar minimum, when the…
The Nuclear Stellar Cluster in the Seyfert 1 Galaxy NGC 3227: High Angular Resolution Near-Infrared Imaging and Spectroscopy
Tacconi, L. J.; Schinnerer, E.; Eckart, A.
Near-infrared (NIR) high angular resolution speckle imaging and imaging spectroscopy of the nuclear region (~10''~840 pc) of the Seyfert 1 galaxy NGC 3227 are presented. The images reveal an unresolved nuclear source in the K band in addition to a nuclear stellar cluster that is slightly resolved in the J and H bands. The contribution o…
Coordinated 1996 HST and IRTF Imaging of Neptune and Triton. I. Observations, Navigation, and Differential Deconvolution
Baines, K. H.; Sromovsky, L. A.; Fry, P. M. +3 more
On 13-14 August 1996, we carried out the first coordinated contemporaneous imaging of Neptune, using the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 and the NASA Infrared Telescope Facility (IRTF) NSFCAM InSb camera to obtain high spatial resolution absolutely calibrated imagery at wavelengths from 0.2 to 2.5 µm. We used nine …
Discovery of anomalous oxygen isotopic ratios in HR 4049
Yamamura, I.; Cami, J.
We report the discovery in the ISO/SWS spectrum of the post-AGB star