Search Publications
Pre-main-sequence stars in the Lagoon Nebula (M8)*
Barbá, R. H.; Morrell, N. I.; Arias, J. I.
We report the discovery of new pre-main-sequence (PMS) stars in the Lagoon Nebula (M8) at a distance of 1.25 kpc, based on intermediate-resolution spectra obtained with the Boller & Chivens spectrograph at the 6.5-m Magellan I Telescope (Las Campanas Observatory, Chile). According to the spectral types, the presence of emission lines and the l…
Mid-Infrared Photometry of Mass-losing Asymptotic Giant Branch Stars
Corcione, L.; Guandalini, R.; Busso, M. +2 more
We present ground-based mid-IR imaging for 27 M-, S-, and C-type asymptotic giant branch (AGB) stars. The data are compared with those of the database available thanks to the IRAS, Infrared Space Observatory, Midcourse Space Experiment, and Two Micron All Sky Survey catalogs. Our goal is to establish relations between the IR colors, the effective …
Near-surface winds at the Huygens site on Titan: Interpretation by means of a general circulation model
Tokano, Tetsuya
This study aims at interpreting the zonal and meridional wind in Titan's troposphere measured by the Huygens probe by means of a general circulation model. The numerical simulation elucidates the relative importance of the seasonal variation in the Hadley circulation and Saturn's gravitational tide in affecting the actual wind profile. The observe…
High resolution mapping of TiO2 abundances on the Moon using the Hubble Space Telescope
Pieters, C. M.; Ulmer, M. P.; Bell, J. F. +4 more
Samples of the lunar regolith returned by Apollo astronauts show large variations (0 to >10 wt%) in TiO2 abundance indicating complex compositional zonation within the lunar mantle. A long held goal of the lunar science community is the accurate determination of TiO2 abundances on the lunar surface through remote sensing m…
ISO far-infrared observations of the high-latitude cloud L1642 . II. Correlated variations of far-infrared emissivity and temperature of "classical large" dust particles
Juvela, M.; Lemke, D.; Russeil, D. +2 more
Aims:Our aim is to compare the infrared properties of big, "classical" dust grains with visual extinction in the cloud
Methods: The far-infrared properties of dust are based on large-scale 100 µm and 200 &…
Magnetic Stereoscopy of Coronal Loops in NOAA 8891
Feng, L.; Inhester, B.; Gan, W. Q. +3 more
The Solar TErrestrial RElations Observatory (STEREO) requires powerful tools for the three-dimensional (3D) reconstruction of the solar corona. Here we test such a program with data from SOHO and TRACE. By taking advantage of solar rotation, a newly developed stereoscopy tool for the reconstruction of coronal loops is applied to the solar active r…
Cluster and nebular properties of the central star-forming region of NGC 1140
Crowther, P. A.; Smith, L. J.; de Grijs, R. +2 more
We present new high spatial resolution Hubble Space Telescope/Advanced Camera for Surveys (ACS) imaging of NGC 1140 and high spectral resolution Very Large Telescope/Ultraviolet and Visual Echelle Spectrograph spectroscopy of its central star-forming region. The central region contains several clusters, the two brightest of which are clusters 1 an…
Doppler Velocities Measured in Coronal Emission Lines from a Bright Point Observed with the EUNIS Sounding Rocket
Brosius, Jeffrey W.; Thomas, Roger J.; Rabin, Douglas M.
Spectroscopic measurements of a coronal bright point obtained with the Extreme Ultraviolet Normal Incidence Spectrograph (EUNIS) sounding rocket instrument on 2006 April 12 show both upflows and downflows in all five of the best observed emission lines. Relative velocities on opposite sides of the feature were found to be +/-15 km s-1 i…
Saturn's Rings at True Opposition
French, Richard G.; Dones, Luke; Salo, Heikki +2 more
On 2005 January 14, the Saturn system was observed at true opposition with the planetary camera of the Wide Field Planetary Camera 2 (WFPC2) on the Hubble Space Telescope. This was the culmination of nearly a decade of similar UBVRI observations, yielding a uniform set of over 400 high spatial resolution and photometrically accurate radial profile…
On the nature of optical nuclei in FR I radio-galaxies from ACS/HST imaging polarimetry
Capetti, A.; Sparks, W. B.; Chiaberge, M. +4 more
We obtained optical imaging polarimetry with the ACS/HRC aboard the HST of the 9 closest radio-galaxies in the 3C catalogue with an FR I morphology. The nuclear sources seen in direct HST images in these galaxies are found to be highly polarized with levels in the range ~2-11% with a median value of 7%. We discuss the different mechanisms that pro…