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Discovery of a Young Substellar Companion in Chamaeleon
Luhman, K. L.; Smith, J. D.; Brandner, W. +6 more
During an imaging survey of the Chamaeleon I star-forming region with the Advanced Camera for Surveys aboard the Hubble Space Telescope, we have discovered a candidate substellar companion to the young low-mass star CHXR 73 (τ~2 Myr, M~0.35 Msolar). We measure a projected separation of 1.30"+/-0.03" for the companion, CHXR 73 B, which c…
First Scattered Light Images of Debris Disks around HD 53143 and HD 139664
Kalas, Paul; Fitzgerald, Michael P.; Graham, James R. +1 more
We present the first scattered light images of debris disks around a K star (HD 53143) and an F star (HD 139664) using the coronagraphic mode of the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). With ages of 0.3-1 Gyr, these are among the oldest optically detected debris disks. HD 53143, viewed ~45° from edge-on, doe…
INTEGRAL observations of the blazar 3C 454.3 in outburst
Maraschi, L.; Tagliaferri, G.; Ghisellini, G. +22 more
In Spring 2005, the blazar 3C 454.3 underwent a dramatic outburst at all wavelengths from mm to X-rays. This prompted INTEGRAL observations, accomplished in 15-18 May 2005. The source was detected by the INTEGRAL instruments from 3 to 200 keV in a bright state (∼ 5 × 10-10 erg s-1 cm-2), at least a factor of 2-3 hi…
Orbits and Photometry of Pluto's Satellites: Charon, S/2005 P1, and S/2005 P2
Stern, S. Alan; Young, Leslie A.; Buie, Marc W. +2 more
We present new astrometry of Pluto's three satellites from images taken of the Pluto system during 2002-2003 with the High Resolution Camera mode of the Advanced Camera for Surveys instrument on the Hubble Space Telescope. The observations were designed to produce an albedo map of Pluto, but they also contain images of Charon and the two recently …
Mid-Infrared Spectroscopy of Carbon Stars in the Small Magellanic Cloud
Price, S. D.; Wood, P. R.; Matsuura, M. +3 more
We have observed a sample of 36 objects in the Small Magellanic Cloud (SMC) with the Infrared Spectrometer on the Spitzer Space Telescope. Nineteen of these sources are carbon stars. An examination of the near- and mid-infrared photometry shows that the carbon-rich and oxygen-rich dust sources follow two easily separated sequences. A comparison of…
Titan Radar Mapper observations from Cassini's T3 fly-by
Stiles, B.; Kelleher, K.; Callahan, P. +32 more
Cassini's Titan Radar Mapper imaged the surface of Saturn's moon Titan on its February 2005 fly-by (denoted T3), collecting high-resolution synthetic-aperture radar and larger-scale radiometry and scatterometry data. These data provide the first definitive identification of impact craters on the surface of Titan, networks of fluvial cha…
First observation of Mars with XMM-Newton. High resolution X-ray spectroscopy with RGS
Holmström, M.; Gunell, H.; Burwitz, V. +7 more
In the first observation of Mars with XMM-Newton, on 20-21 November 2003, this planet is clearly detected as an X-ray source. High resolution X-ray spectroscopy with the Reflection Grating Spectrometer (RGS) confirms that the X-ray radiation from Mars is composed of two different components: one due to fluorescent scattering of solar X-rays in its…
A FUSE Survey of High-Latitude Galactic Molecular Hydrogen
Wakker, B. P.
Measurements of molecular hydrogen (H2) column densities are presented for the first six rotational levels (J=0-5) for 73 extragalactic targets observed with the Far Ultraviolet Spectroscopic Explorer (FUSE). All of these have a final signal-to-noise ratio larger than 10 and are located at Galactic latitude |b|>20deg. The …
The broad-band spectrum of Cygnus X-1 measured by INTEGRAL
Goldoni, P.; Rodriguez, J.; Foschini, L. +9 more
The INTEGRAL satellite extensively observed the black hole binary Cygnus X-1 from 2002 November to 2004 November during calibration, open time and core program (Galactic Plane Scan) observations. These data provide evidence for significant spectral variations over the period. In the framework of the accreting black hole phenomenology, the source w…
Unveiling the nature of INTEGRAL objects through optical spectroscopy. III. Observations of seven southern sources
Palazzi, E.; Masetti, N.; Charles, P. A. +9 more
Context: . The detection, thanks to the INTEGRAL satellite, of a number of new hard X-ray sources calls for the identification of their nature by means of observations at longer wavelengths. Aims. In our continuing campaign to identify longer-wavelength counterparts of these newly-discovered hard X-ray sources detected by INTEGRAL, we observed the…