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Differentiation of the asteroid Ceres as revealed by its shape
The accretion of bodies in the asteroid belt was halted nearly 4.6 billion years ago by the gravitational influence of the newly formed giant planet Jupiter. The asteroid belt therefore preserves aExpand
SN 1991bg - A type Ia supernova with a difference
We present 13 spectra and 31 photometric observations covering the first 150 days of SN 1991bg in NGC 4374 (M 84). Although SN 1991bg was a type Ia supernova displaying the characteristic Si IIExpand
The stellar content of NGC 346: A plethora of O stars in the SMC
The stellar content of NGC 346, the largest and brightest H II region in the SMC, was investigated using the results of CCD UBV photometry and spectroscopy. Spectra of 42 blue stars were classified,Expand
HST/FOS Spatially Resolved Spectral Classification of Compact OB Groups in the Large Magellanic Cloud*
Blue-violet spectrograms of individual components in four compact OB groups of the Large Magellanic Cloud, obtained with the Hubble Space Telescope (HST) Faint Object Spectrograph (FOS), areExpand
The OB associations of 30 Doradus in the Large Magellanic Cloud. I - Stellar observations and data reductions
UBV photometry is presented for 2400 stars in the OB associations of 30 Doradus in the Large Magellanic Cloud, and I discuss new spectroscopic observations of 54 stars including 24 O stars. The CCDExpand
The stellar content of LH 9 and 10 (N11) in the LMC - A case for sequential star formation
The young OB associations Lucke-Hodge 9 and 10 are studied with UBV photometry that is independent of reddening to determine the IMF directly from star counts. The temperature and reddening of theExpand
Surface compositions across Pluto and Charon
New Horizons unveils the Pluto system In July 2015, the New Horizons spacecraft flew through the Pluto system at high speed, humanity's first close look at this enigmatic system on the outskirts ofExpand
Ultraviolet Imaging Telescope Observations of the Magellanic Clouds
We present wide-field far-ultraviolet (FUV; 1300–1800 A) images of the Large and Small Magellanic Clouds (LMC, SMC). These data were obtained by the Ultraviolet Imaging Telescope (UIT) during theExpand
Photometric analysis of 1 Ceres and surface mapping from HST observations
The highest resolution (pixel scale 30 km) images of Ceres to date have been acquired by the Advanced Camera for Surveys onboard Hubble Space Telescope, through three wide band filters, centered atExpand
Analysis of the First Disk-resolved Images of Ceres from Ultraviolet Observations with the Hubble Space Telescope
We present Hubble Space Telescope Faint Object Camera observations of the asteroid 1 Ceres at near-, mid-, and far-UV wavelengths (λ = 3636, 2795, and 1621 A, respectively) obtained on 1995 June 25.Expand