An atlas of the optical spectrum of supernova 1987A in the large magellanic cloud     

V. J. Mclntyre  A. C. Gilmore  J. B. Hearnshaw 《Journal of Astrophysics and Astronomy》1990,11(1):81-123

Photographic spectra of SN1987A in the LMC have been obtained from 1987 February 25 to 1988 June 30. Microdensitometer tracings of these have been reduced to intensity and corrections for instrumental response have been applied to the spectra. This paper presents these data in an atlas format, discusses the reduction procedures in detail, and presents radial velocity measurements of selected lines in the spectra  相似文献   

Spectroscopic binaries near the North Galactic Pole paper 18: HD 118670     

R. F. Griffin 《Journal of Astrophysics and Astronomy》1990,11(4):533-540

Photoelectric radial-velocity measurements show that HD 118670 is a double-lined spectroscopic binary in an orbit which is not quite circular and whose period is about 48 days. Spectral types of K0 V and K7 V would satisfy the photometry and the mass ratio; the mass function would then suggest the possibility of eclipses. However, actual spectral classification indicates a luminosity somewhat above the main sequence  相似文献   

鞍山地区中、上鞍山群变质沉积岩中黑云母化学成分及其意义     

刘道荣 《国土资源》1990,(3)

通过对中、上鞍山群变质沉积岩中黑云母化学成分的对比,确认区内两层位黑云母化学组分存在一定差异,这种差异主要反映了其形成时变质条件的不同。随变质程度增加,区内黑云母的Si、AI~Ⅵ,Fe~(3 )、Mg和K含量增加,而Fe~(2 )、Al~Ⅳ和CH降低,Mg/Fe~(2 )比值从1.00增至2.18。中鞍山群黑云母变质温度为550—620℃,变质压力在5×10~8Pa左右;上鞍山群黑云母变质温度为450-500℃,变质压力低于5×10~8Pa。黑云母含铁系数(f)可作为鞍山地区寻找富铁矿的一种标志。  相似文献   

Mapping of Io's thermal radiation by the Galileo photopolarimeter-radiometer (PPR) instrument   总被引：1，自引：0，他引：1  

J.A. Rathbun  J.R. Spencer  T.Z. Martin  L.D. Travis 《Icarus》2004,169(1):127-139

Between 1999 and 2002, the Galileo spacecraft made 6 close flybys of Io during which many observations of Io's thermal radiation were made with the photopolarimeter-radiometer (PPR). While the NIMS instrument could measure thermal emission from hot spots with T>200 K, PPR was the only Galileo instrument capable of mapping the lower temperatures of older, cooling lava flows, and the passive background. We tabulate all data taken by PPR of Io during these flybys and describe some scientific highlights revealed by the data. The data include almost complete coverage of Io at better than 250 km resolution, with extensive regional coverage at higher resolutions. We found a modest poleward drop in nighttime background temperatures and evidence of thermal inertia variations across the surface. Comparison of high spatial resolution temperature measurements with observed daytime SO₂ gas pressures on Io provides evidence for local cold trapping of SO₂ frost on scales smaller than the 60 km resolution of the PPR data. We also calculated the power output from several hot spots and estimated total global heat flow to be about 2.0-2.6 W m⁻². The low-latitude diurnal temperature variations for the regions between obvious hot spots are well matched by a laterally-inhomogeneous thermal model with less than 1 W m⁻² endogenic heat flow.  相似文献   

Ground-based photometric observations of Jupiter's inner satellites Thebe, Amalthea, and Metis at small phase angles     

I. Kulyk  K. Jockers 《Icarus》2004,170(1):24-34

We present the results of photometric measurements of the inner jovian satellites Thebe, Amalthea and Metis based on extensive optical observations taken from October 1999 to January 2002. The observations were made in the phase angle range from 8.1° to 0.3°. The Two-Channel Focal Reducer of the Max-Planck Institute for Aeronomy attached to the 2-m RCC telescope at Terskol Observatory (Pik Terskol, Northern Caucasus) was used in coronagraph mode. The observations were performed at a wavelength of 0.887 μm. Mean observational uncertainties corresponding to 1σ rms errors were 3% for the leading and trailing sides of Amalthea, 7 and 9% for the leading and trailing sides of Thebe and 9% for the leading side of Metis after taking into account the longitude brightness variations. Photometric data calibrated on an absolute scale were used to evaluate the near-opposition behavior of satellite brightness. All three satellites exhibit significant opposition brightening, but the strength of this effect, measured as the ratios of intensities at α₁=1.6° and α₂=6.7° does not vary significantly among these satellites. In order to measure the opposition surge parameters the empirical law proposed by Karkoschka and Hapke's model were used. The parameters of the satellite opposition effects are presented and discussed. The values of geometric albedos calculated with best-fit Hapke parameters are 0.096, 0.157, and 0.24 for Thebe, Amalthea, and Metis respectively. We found that the average leading/trailing ratios of surface reflectance at the measured phase angles are 1.53±0.05, 1.25±0.04, 1.04±0.08 for Amalthea, Thebe, and Metis.  相似文献   

Dust-reddening and gravitational lensing of SDSS QSOs due to foreground damped Lyman α systems     

M. T. Murphy  J. Liske 《Monthly notices of the Royal Astronomical Society》2004,354(2):L31-L36

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The young open cluster Markarian 50     

Gustavo Baume  Rubén A. Vázquez  Giovanni Carraro 《Monthly notices of the Royal Astronomical Society》2004,355(2):475-484

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The energy balance of polars revisited     

Gavin Ramsay  Mark Cropper 《Monthly notices of the Royal Astronomical Society》2004,347(2):497-507

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Colour variability of asteroids in the Sloan Digital Sky Survey Moving Object Catalog     

Gy. M. Szabó  &#;. Ivezi&#; †  M. Juri&#;  R. Lupton  L. L. Kiss 《Monthly notices of the Royal Astronomical Society》2004,348(3):987-998

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The effect of rotational gravity darkening on magnetically torqued Be star discs     

J. C. Brown  D. Telfer  Q. Li  R. Hanuschik  J. P. Cassinelli  A. Kholtygin 《Monthly notices of the Royal Astronomical Society》2004,352(3):1061-1072

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