scholarly journals Observations of Gas and Dust in Comets with the Infrared Space Observatory

2000 ◽  
Vol 197 ◽  
pp. 461-470 ◽  
Author(s):  
J. Crovisier
Keyword(s):  
High Resolution ◽  
Thermal Infrared ◽  
Infrared Region ◽  
Production Rates ◽  
Space Observatory ◽  
Infrared Space Observatory ◽  
Water Ice ◽  
Spectroscopic Observations ◽  
Celestial Bodies

The Infrared Space Observatory (ISO) offered us the opportunity to observe celestial bodies from 2.4 to 196 μm, which is of particular interest for comets. We present here spectroscopic observations with ISO of comets C/1995 O1 (Hale-Bopp) and 103P/Hartley 2. Fluorescence emissions of H2O, CO2 and (for comet Hale-Bopp only) CO and CH4 are observed, yielding the production rates of these species. High-resolution spectra of water permit the study of the rotational and spin temperatures of this molecule. In comet Hale-Bopp, the thermal infrared region of the spectra shows specifically, in addition to continuum-like emission, the signatures of crystalline, Mg-rich olivine (forsterite), and signs of crystalline pyroxenes, amorphous silicates and water ice. The presence of crystalline silicates is also suggested in the Jupiter-family comet P/Hartley 2.

scholarly journals ISO Observations of Comets

2005 ◽  
Vol 13 ◽  
pp. 761-761
Author(s):  
Dominique Bockelée-Morvan
Keyword(s):  
Rotational Temperature ◽  
Broad Band ◽  
Color Temperature ◽  
Rotational Line ◽  
Space Observatory ◽  
Infrared Space Observatory ◽  
Water Ice ◽  
Cometary Dust ◽  
Thermal Region ◽  
Celestial Bodies

The Infrared Space Observatory (ISO) offered us the opportunity to observe celestial bodies from 2.4 to 196 microns. A wealth of new results were obtained for comets. Spectroscopic investigations have shown band fluorescence emissions for H2O, CO and CO2, and rotational line emissions for H2O. High resolution spectra of water vapor around 2.7 microns in comets C/1995 01 (Hale-Bopp) and 103P/Hartley 2 have permitted measurement of the water rotational temperature and ortho-to-para ratio. The thermal region of the spectra showed the signatures of crystalline, Mg-rich olivine and emission features attributed to water ice. Broad band photometry of the coma allowed to investigate several properties of cometary dust, such has color temperature, size distribution and production rate. For several comets, it was possible to separate the nuclear and coma contribution in infrared images obtained from the ISO camera. Inferences concerning the nucleus size and albedo were obtained.

scholarly journals AGN Spectra as Seen by the Infrared Space Observatory: First Results

1997 ◽  
Vol 159 ◽  
pp. 333-336
Author(s):  
D. Lutz ◽  
R. Genzel ◽  
E. Sturm ◽  
A.F.M. Moorwood ◽  
E. Oliva ◽  
...  
Keyword(s):  
Fine Structure ◽  
Short Wavelength ◽  
Molecular Hydrogen ◽  
Molecular Gas ◽  
Space Observatory ◽  
Infrared Space Observatory ◽  
First Results ◽  
External Galaxies ◽  
First Time ◽  
Fine Structure Lines

AbstractWe discuss 2.5–45 µm spectra of the Circinus galaxy and of Cen A, obtained with the Short Wavelength Spectrometer (SWS) on board the Infrared Space Observatory. The large number of detected ionic fine structure lines, observable also in visually obscured sources, provides strong constraints on the shape of the ionizing spectrum, which is found to exhibit a UV bump peaking at ~ 70 eV in the case of Circinus. Pure rotational emission of molecular hydrogen, directly probing warm molecular gas, can for the first time be detected in external galaxies.

The 2.4– spectrum of Mars observed with the infrared space observatory

2000 ◽  
Vol 48 (12-14) ◽  
pp. 1393-1405 ◽  
Author(s):  
E Lellouch ◽  
T Encrenaz ◽  
T de Graauw ◽  
S Erard ◽  
P Morris ◽  
...  
Keyword(s):  
Space Observatory ◽  
Infrared Space Observatory

scholarly journals Seyfert galaxies: a perspective with ISO-PHOT

1999 ◽  
Vol 193 ◽  
pp. 750-751
Author(s):  
Ana M. Pérez García ◽  
J.M. Rodríguez Espinosa
Keyword(s):  
Temperature Distribution ◽  
Far Infrared ◽  
Seyfert Galaxies ◽  
Inversion Method ◽  
Space Observatory ◽  
Infrared Space Observatory ◽  
Energy Distributions ◽  
Spectral Components ◽  
Ir Emission

We present mid and far-infrared energy distributions of the CfA Seyfert sample, obtained with the Infrared Space Observatory photometer (ISO-PHOT). To analyse the CfA Seyfert SEDS, we apply an inversion method: the Inverse Planckian Transform, assuming that the mid- and far-IR emission is thermal. We obtain the spectral temperature distribution of sources that reproduces the observed SEDS. We compare the parameters of the spectral components found showing that there are not differences between Seyfert 1 and Seyfert 2 as for their temperatures while the emission between 12 and 25 μm is anisotropic.

ISOCAM--the Infrared Space Observatory camera: results of testing and calibrations

1993 ◽  
Author(s):  
Laurent G. Vigroux ◽  
Catherine J. Cesarsky ◽  
Olivier Boulade ◽  
Yvon Rio ◽  
Michel Perault ◽  
...  
Keyword(s):  
Space Observatory ◽  
Infrared Space Observatory
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