J/A+A/599/A29 MIR brightness contrast of Saturn's rings (Fujiwara+, 2017)
Seasonal variation of radial brightness contrast of Saturn's rings viewed in
mid-infrared by Subaru/COMICS.
Fujiwara H., Morishima R., Fujiyoshi T., Yamashita T.
<Astron. Astrophys. 599, A29 (2017)>
=2017A&A...599A..29F 2017A&A...599A..29F (SIMBAD/NED BibCode)
ADC_Keywords: Solar system ; Planets ; Photometry, infrared
Keywords: planets and satellites: rings - infrared: planetary systems
Abstract:
To investigate the mid-infrared (MIR) characteristics of Saturn's
rings.
We collected and analyzed MIR high spatial resolution images of
Saturn's rings obtained in January 2008 and April 2005 with COMICS
mounted on Subaru Telescope, and investigated the spatial variation in
the surface brightness of the rings in multiple bands in the MIR. We
also composed the spectral energy distributions (SEDs) of the C, B,
and A rings and the Cassini Division, and estimated the temperatures
of the rings from the SEDs assuming the optical depths.
We find that the C ring and the Cassini Division were warmer than the
B and A rings in 2008, which could be accounted for by their lower
albedos, lower optical depths, and smaller self-shadowing effect. We
also find that the C ring and the Cassini Division were considerably
brighter than the B and A rings in the MIR in 2008 and the radial
contrast of the ring brightness is the inverse of that in 2005, which
is interpreted as a result of a seasonal effect with changing
elevations of the sun and observer above the ring plane.
Description:
Brightness maps for Saturn's rings at 8.8, 9.7, 10.5, 11.7, 12.5,
17.7, 18.8, 20.5, and 24.5 micron observed with Subaru
Telescope/COMICS in 2008 and at 12.5 and 24.5 micron in 2005 are
provides as fits files.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 44 11 List of fits images
fits/* . 11 Individual fits images
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Year Year of Observation (UT)
6- 10 A5 --- Filter Filter Name
12- 14 I3 --- Nx Number of pixels along X-axis
16- 18 I3 --- Ny Number of pixels along Y-axis
20- 22 I3 Kibyte FileSize Size of FITS file
24- 44 A21 --- FileName Name of FITS file, in subdirectory fits
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Acknowledgements:
Hideaki Fujiwara, hideaki(at)naoj.org
(End) Patricia Vannier [CDS] 12-Dec-2016