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1.
V andB observations of V711 Tauri (HR 1099) for the year 1982–1983 are presented. The light curves made with the data of this season are compared with those of the previous observations of the 1981–1982 season. The single-peaked maximum light had shifted slightly and the peak amplitude had decreased to 0.04 mag. inV. No clear sign of colour,B–V, variation in comparison with the low temperature dark-spot is detected.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
2.
Ursula B. Marvin 《Meteoritics & planetary science》1993,28(3):261-314
Abstract— In August, 1933, at the Field Museum of Natural History in Chicago, The Society for Research on Meteorites was founded with an enrollment of 57 charter members and Frederick C. Leonard and Harvey H. Nininger as the first President and Secretary-Treasurer, respectively. Within five years, the Society had doubled in size, with members from the U.S.A. and ten other nations. Annual meetings were suspended during World War II (1942 through 1945) and when it reconvened in 1946 the members adopted the name “The Meteoritical Society”. By that time personal and professional antagonisms had arisen that threatened to fragment the Society and led, in 1949, to the resignation of Nininger and his wife. Throughout the 1950s the Society was widely regarded as a small, disorganized and essentially moribund organization. Revitalization of the Society began in the early 1960s after the advent of the Space Age when the Society steadily gained members with expertise in mineralogy, petrology, isotope geochemistry, electron microprobe and neutron activation analysis, and impact dynamics. When Nininger was persuaded rejoin in 1963, he found a renewed Society. In the election year of 1966 a group of youthful insurgents nominated an alternate slate to that proposed by the Council and won every contested seat on the Council except that of the Editor. The Society's first publication Contributions of the Society for Research on Meteorites was published as a section of Popular Astronomy and from 1935 to 1946 reprints of the items (articles, reviews, and notices) were bound and distributed separately each year. When the Society changed its name in 1946, its journal became Contributions of the Meteoritical Society, which continued publication until Popular Astronomy ceased publication in 1952. A new journal, Meteoritics, was instituted in 1953. After 1956, its publication lapsed for six years but began again in 1963 and has continued under the leadership of four successive editors becoming one of the most frequently cited geoscience journals. In 1970, the Society also became a co-sponsor with The Geochemical Society of Geochimica et Cosmochimica Acta, but the future of this arrangement remains in doubt. In 1938, the Society had gained considerable prestige by its acceptance as a full Affiliate of the American Association for the Advancement of Science, but in view of its increasingly international membership and activities the Society terminated its affiliation with the AAAS in 1976. Again in response to its international status, in 1992 The Meteoritical Society affiliated with the International Union of Geological Sciences. The Society held its first annual meeting outside North America at the Universität Tübingen in West Germany in 1971. Subsequently, it met in Europe every second year until 1990, when it met at Perth in Western Australia. During the 1980s, the membership of the Society grew to more than 900 and the annual meetings attracted between 300 and 450 participants. As meteoritical research continues to probe the borderlands with astrophysics, planetary science, and terrestrial geology, and as younger members assume leadership roles, a productive future seems assured for both meteoritical science and The Meteoritical Society. 相似文献
3.
The night-to-night and short-term variations inUBV light curves of EW Lac which were made during 1982–1984 at Yonsei University Observatory are discussed. The long-term variability in the photometric behaviour of the star is examined with our own data as well as those of Harmanecet al. (1980).Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.Yonsei University Observatory Contribution No. 23. 相似文献
4.
Nova Aquilae 1982 was observed spectroscopically and photometrically in January, February, and April 1982. The results of these observations including those obtained a few days after the discovery, are presented.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
5.
The long-term variations of EW Lac in the H and H line profiles are presented. The active phase observed in 1978–1982 is characterized by the strengthening of emission lines accompanied by variations of radial velocities andV/R asymmetries. A model of a rotating elliptic ring is proposed.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
6.
Bart J. Bok 《Earth, Moon, and Planets》1978,19(2):153-155
The principal properties of dark globules are reviewed. Optical and radio (CO) data suggest masses in the range 20 to 750M
, radii 0.15 to 1.2 parsecs. There is no evidence for fragmentation. The dust density inside near-spherical globules varies inversely as the cube of the distance from the center. There is evidence to show that several globules are in a state of collapse.Paper presented at the Conference on Protostars and Planets, held at the Planetary Science Institute, University of Arizona, Tucson, Arizona, between January 3 and 7, 1978.Much of the work was done while the author was a Visiting Scientist at Cerro Tololo Interamerican Observatory in Chile, supported by the National Science Foundation under Contract No. NSF-C866. 相似文献
7.
This report summarises a Royal Astronomical Society (RAS) Specialist Discussion Meeting held on 2001 December 14 in the rooms
of the Geological Society, Burlington House, London. The meeting was well attended, with approximately 100 Fellows and guests
being present, and attracted considerable interest from the media. Two associated talks, given byinvited international speakers,
were also presented as part of the mainRAS Astronomy & Geophysics Meeting held the same day at the Scientific Societies' Lecture
Theatre in Savile Row, as reported below in closing this summary.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
In this paper the solar neutron and white-light flare is studied on the basis of radioastronomical observations. It is shown that the 3 June, 1982 flare had an impulsive character. A strong shock wave (M
A
2.9) was observed unusually soon after the impulsive phase of the flare. The radio spectrum of this event shows that the primary acceleration process probably occurred in the region with an electron density of n
e
= 4.4 × 1015 m–3. The pulsations of the type IV radio burst, observed 15 min after the mass ejection process, manifest the reconnection process in the post-flare stage.Proceedings of the Workshop on Radio Continua during Solar Flares, held at Duino (Trieste), Italy, 27–31 May, 1985. 相似文献
9.
Masaki Morimoto 《Astrophysics and Space Science》1986,118(1-2):63-65
The title telescope — in operation since 1982 — gives a surface accuracy of better than 0.2 mm (r.m.s.), with an aperture efficiency of about 25% at 115 GHz. A 5-element interferometer is at final adjustment stage. Observations of proto-stellar objects, extragalactic objects, and spectral lines are briefly described.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984. 相似文献
10.
Results are shown for photoelectric B and V observations of Markarian 421 (Mrk 421) from 1982 to 1991. It is found that one can explain the dependence of the color indices (B-V) averaged for a season on the B magnitude within a two-component model (an underlying galaxy + a variable point source). It is determined that the color index (B-V)
var
of the variable source does not change, and the observed variability of the color index is caused by variation of the contribution from the variable source to the total flux.Translated from Astrofizika, Vol. 37, No. 2, pp. 285–300, April–June, 1994.V. A. Hagen-Thorn and V. A. Yakovleva are grateful to the American Astronomical Society for financial support in 1993. 相似文献
11.
Farouk M. Mahmoud 《Astrophysics and Space Science》1993,208(2):217-227
Long-term changes in two flare stars, EV Lac and BY Dra, have been detected by Mavridiset al. (1982). These long cyclic periods have been registered in theB-band at their quiescent-state luminosity as well as at their flare activity. Those observational data of the two previously mentioned flare stars as well as another observational data of the flare star, UV Cet, at its flare activity were submitted to our computer programme for periodicity detection excluding cyclic periods which have amplitudes less than tenth magnitude for great significance. Some of our results coincided with the long cyclic periods detected by Mavridiset al. (1982) while the remainder of our results have had no complete coincidence with those registered by Mavridiset al. (1982). 相似文献
12.
Steady state level density of 20 levels of boron-like ions, Mg viii and Si x, have been computed as a function of electron density and temperature. We have accounted for collisional and spontaneous radiative processes. Photo-excitation between the two levels of the ground term has also been considered. Using the computed level density, line intensities have been obtained as a function of electron density and temperature. In case of Mg viii, line intensity ratio I(430.47)/I(436.62) is found to be electron density sensitive. Likewise other pairs of lines namely, I(75.03)/I(74.86), I(315.02)/I(430.47), and I(315.02)/I(335.23) are also found to be density sensitive. Similar density sensitive line intensity ratios have been found for Si x. Absolute line fluxes from these ions at earth distance have been computed and are found to be comparable with values obtained, using various satellite and rocket measurements.Paper presented at the 5th Astronomical Society of India Meeting, held at Uttar Pradesh State Observatory, Naini Tal, India, 5–9 November, 1979. 相似文献
13.
This paper presents an analysis of the phase‐calibration problem encountered in astronomy when mapping incoherent sources with aperture‐synthesis devices. More precisely, this analysis concerns the phase‐calibration operation involved in the self‐calibration procedures of phase‐closure imaging. The paper revisits and completes a previous analysis presented by Lannes in the Journal of the Optical Society of America A in 2005. It also benefits from some recent developments made for solving similar problems encountered in global navigation satellite systems. In radio‐astronomy, the related optimization problems have been stated and solved hitherto at the phasor level. We present here an analysis conducted at the phase level, from which we derive a method for diagnosing and solving the difficulties of the phasor approach. In the most general case, the techniques tobe implemented appeal to the algebraic graph theory and the algebraic number theory. The minima of the objective functionals to be minimized are identified by raising phase‐closure integer ambiguities. We also show that in some configurations, to benefit from all the available information, closure phases of order greater than three are to be introduced. In summary, this study leads to a better understanding of the difficulties related to the very principle of phase‐closure imaging. To circumvent these difficulties, we propose a strategy both simple and robust (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
14.
Photoelectric observations of the RS CVn type non-eclipsing binary UX Arietis obtained at Nizamiah Observatory during the
observing seasons of 1975–76, 1981–82 and 1982–83 are presented. The light curve of UX Ari showed a distortion wave with an
amplitude inV varying from 0.02 mag during 1975–76 to 0.15 mag during 1982–83. An analysis of the available data shows that the light maximum
is almost constant. It is also evident that the light-curve minimum decreases as the wave amplitude increases. The constant
light at maximum,V = 6.51 ± 0.03 indicates the unspotted photospheric brightness. It is also suggested that the variation in meanV brightness is mainly due to spot activity and not due to intrinsic variation. 相似文献
15.
元素丰度与星系演化(Stellar Abundance and Galactic Evolution,SAGE)是自主设计的能够准确计算恒星大气参数以及消光的新测光系统。对北天除银盘外共计约12 000 deg2的天区开展了SAGE系统测光巡天,计划获取约5亿颗恒星的高精度测光数据。单次曝光条件下100σ完备星等uSC～17. 3,vSAGE～16. 8(AB星等),这些为研究银河系提供宝贵的测光资料。介绍了巡天专用的数据处理程序的研究和开发,主要研究了针对单幅图像的快速自动化处理过程,重点介绍数据改正、天体测量校正、测光和流量定标过程,以及数据结果和数据质量检测等。 相似文献
16.
A. V. Raveendran 《Astrophysics and Space Science》1984,99(1-2):171-173
Photometry of the spectroscopic binary BD+25°2511 obtained during the 1981, 1982, and 1983 observing seasons shows that it is a variable with a period of about 3.5 days.Paper presented at the Lembang-Bamberg IAU Colloquium No. 80 on Double Stars: Physical Properties and Generic Relations, held at Bandung, Indonesia, 3–7 June, 1983. 相似文献
17.
P. D. Singh K. Sinha B. M. Tripathi Heloisa M. B. Roberty 《Earth, Moon, and Planets》1989,47(3):231-239
Post-perihelion observed emission fluxes at 388 nm (CN) and 516 nm (C2) of the coma of comets Austin (1982g) and Bradfield (1980t) are analysed in the framework of the Haser model. Ratios of Haser model CN and C2 parent production rates with expansion velocity show that each comet behaves normally. For comet Austin (1982g), the Q
CN/v and Q
c2/v values decrease with increase of heliocentric distance of comet. For an assumed %; activity of the total spherical surface area of the nucleus, the water vaporization theory coupled with derived water production rates from the International Ultraviolet Explorer H and OH flux data yields a nuclear diameter of about 6 km for comet Austin (1982g). For comet Bradfield (1980t), the derived nuclear diameter is expected to be of about 1 km. In each comet, the dust mass production rates as well as ratio of dust-to-gas mass production rates decrease with increase of heliocentric distance of comet. 相似文献
18.
M. Karlický 《Solar physics》1984,92(1-2):329-342
The paper presents the radio spectra of seven solar flares (May 16, 1981; August 19, 1981; January 31, 1982; February 1, 1982; June 3, 1982; June 7, 1982; and July 12, 1982), whose common feature is the presence of narrowband dm-spikes. A close relationship was found among dm-spikes, dm-pulsations and type II radio bursts. Moreover, all flares under study showed indications of a mass ejection process. Based both on these facts and on the theory of dm-spikes (Kuijpers et al., 1981), our observations can be explained by runaway processes in several small regions within the ejected and tearing magnetic structure of the flare. 相似文献
19.
K. V. K. Iyengar F. Strafella D. Lorenzetti C. B. Cosmovici 《Journal of Astrophysics and Astronomy》1982,3(4):451-463
Using an Infrared photometer with InSb photovoltaic detector at the 182cm Copernicus telescope of the Asiago Observatory,
Italy, we have measured theJHKL’ M magnitudes of 12 IRC sources 7 of which are very late type stars with [ICIT -K] greater than 5 magnitudes. These data have been fitted to blackbody distributions to obtain their effective temperatures.
The present data, in combination with other available photometric data at longer wavelengths seems to indicate excess emission
at 11 μm from sources 10066, 10510 and 10234, and at 19.8 μm from source 20052. The source 60098 shows extreme infrared colours.
Work carried out when the first author was a guest scientist at Max Planck-Institut für Extraterrestrische Physik,Garching FRG. 相似文献
20.
B. Ruiz Cobo J. C. Del Toro Iniesta M. Collados J. Sánchez Almeida 《Astrophysics and Space Science》1990,170(1-2):113-116
The diagnostic method proposed by Landi Degl'Innocenti and Landolfi (1982), based on the observation of circular polarization, has been generalized to derive the thermodynamic properties of unresolved magnetic elements in the solar atmosphere. The final aim is to derive the height dependence of several parameters of the flux tube atmosphere (such as temperature, magnetic field and velocity distributions, macroturbulence and filling factor). We have used a perturbation method based on the concept of response functions for the Stokes profiles introduced by Landi Degl'Innocenti and Landi Degl'Innocenti (1977). We present here the preliminary results of invertingV-profiles by an iterative standard least-squares technique, which allows to find the magnetic 1-D atmosphere consistent with simulated data.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain. 相似文献