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1.
We survey the job situation of women in astronomy in Germany and of German women abroad and review indicators for their career development. Our sample includes women astronomers from all academic levels from doctoral students to professors, as well as female astronomers who have left the field. We find that networking and human support are among the most important factors for success. Experience shows that students should carefully choose their supervisor and collect practical knowledge abroad. We reflect the private situation of female German astronomers and find that prejudices are abundant, and are perceived as discriminating. We identify reasons why women are more likely than men to quit astronomy after they obtain their PhD degree. We give recommendations to young students on what to pay attention to in order tobe on the successful path in astronomy (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

2.
海量多波段星表数据的交叉证认的实现   总被引：2，自引：1，他引：1  
许多天文学家需要星表来选源、证认和研究。目前国外有一些大的数据中心提供了星表查询、多源查询(即小样本交叉证认)、可视化等功能。但是随着大数据量及全波段天文时代的到来,这些服务已经越来越不能满足天文学家的需求。在详细分析了国外数据中心的服务后,提出了新的问题,并给出一套解决方案。着重讨论了任意两个星表的交叉证认和大数据量星表的交叉证认的实现,以及交叉证认结果的分类和参数的自由选择等方面的课题。  相似文献   

3.
We conclude that pulsar-driven supernova remnants (SNRs) are extremely rare objects. Indeed an analysis of the known sample of plerions suggests a very low birthrate ∼ 1 in 240 years. Long-lived and bright plerions like the Crab nebula are likely to be produced only when the pulsar has an initial period ∼ 10–20 milliseconds and a field ∼ 1012 G. Such pulsars inside rapidly expanding shell remnants should also produce detectable plerions. The extreme rarity of SNRs with such hybrid morphology leads us to conclude that these pulsars must have been born with an initial period larger than ∼ 35–70 milliseconds. Joint Astronomy Program, Department of Physics, Indian Institute of Science, Bangalore 560012.  相似文献   

4.
The outburst of X-ray transient source XTE J2012+381 was detected by the RXTE All-Sky Monitor on 1998 May 24th. Following the outburst, X-ray observations of the source were made in the 2–18 keV energy band with the Pointed Proportional Counters of the Indian X-ray Astronomy Experiment (IXAE) on-board the Indian satellite IRS-P3 during 1998 June 2nd–10th. The X-ray flux of the source in the main outburst decreased exponentially during the period of observation. No large amplitude short-term variability in the intensity is detected from the source. The power density spectrum obtained from the timing analysis of the data shows no indication of any quasi-periodic oscillations in 0.002–0.5 Hz band. The hardness ratio i.e. the ratio of counts in 6–18 keV to 2–6 keV band, indicates that the X-ray spectrum is soft with spectral index >2. From the similarities of the X-ray properties with those of other black hole transients, we conclude that the X-ray transient XTE J2012+381 is likely to be a black hole.  相似文献   

5.
The Spanish participation as an Associate Member in the Millimeter Array (MMA) project - led by the U.S. National Radio Astronomy Observatory (NRAO) - has been recently proposed to the Spanish Science and Technology Bureau (OCYT). This request to the Spanish Government is based on two key factors: (1) The high scientific interest and support of the Spanish scientific community, for whom major new fields of research--inaccessible with other instruments--will become available. (2) An industrial return that will clearly benefit Spanish companies developing cutting-edge technology and providing them with a high international profile. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
We have developed a control system for the Seoul Radio Astronomy Observatory (SRAO) 6-meter telescope operating in the 85–115 Ghz frequency range. Four PCs running the Linux operating system control source tracking, take data, execute observations and handle user interface. The control system utilizes a modular and multiprocessing structure to facilitate easy upgrading and troubleshooting. Communication between the processes relies on the interprocess communication (IPC) resources on Linux such as shared memory, message queues, and TCP/IP sockets. Communication between PCs is made via an Ethernet link. We also use digital I/O lines for some status signals which require a short delay. The control system supports scheduling observations, updates observation logs automatically and also supports graphical user interfaces. These all makes the operation easy. By using a commercially available motion control card with an embedded microcomputer for antenna control, we achieved a tracking accuracy to better than 1 arcsec. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
A high resolution spectrum of a sunspot umbra is used for identification of rotational lines due to (0, 0) band of the A 2Π–X 2Σ+ system and (0, 0), (1, 1), and (2, 2) bands of the B 2Σ+–X 2Σ+ system of the molecule SrF. The published sunspot umbral spectrum obtained with Fourier Transform Spectrometer and solar telescope of National Solar Observatory/National Optical Astronomy Observatory at Kitt Peak was used for the study. The new identification of more than 200 SrF lines in the umbral spectrum confirms that this molecule accounts for the majority of lines in the spectral range 15050 to 15360 cm−1 and 17240 to 17300 cm−1. Equivalent widths have been measured for well-resolved lines of these bands and the effective rotational temperatures have been estimated for which the presence is confirmed.  相似文献   

8.
Astronomy as a discipline is essentially online and digital. It thus offers an ideal framework for the examination of current trends in electronic publishing. Electronic publishing is driven on the winds of various underlying technologies. We look at a number of these, focusing on information access and retrieval. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

9.
VLA observations at 6 cm have been obtained for three hydrogen-deficient objects υ Sgr, V 348 Sgr, and A bell 58. A bell 58 was also observed at 2 cm. Only upper limits to the flux density could be set for these sources. A new radio source at 6 cm was found in the field of υ Sgr. The upper limit for 6 cm flux density of V348 Sgr sets an upper limit to its reddening asE(B–V) ≤ 0.65. The hydrogen deficient planetary nebula A 58 shows much lower radio flux than expected from the infrared-radio flux density relationship of planetary nebulae. National Radio Astronomy Observatory’s Very Large Array is operated by Associated Universities Inc. under contract with National Science Foundation, USA.  相似文献   

10.
The variability of the radio source 3C120 is studied using data from the international geodesic VLBI observation programs at 8.6 GHz and regular monitoring over frequencies of 4.8–36.8 GHz carried out at the Crimean Astrophysical Observatory (Ukraine) and the Radio Astronomy Observatory of the University of Michigan (USA). A combined analysis of the integral fluxes and structures on millisecond scales reveals the existence of flares at high frequencies accompanied by the appearance of new VLBI components at centimeter wavelengths. It is found that the variations in the fluxes for 3C120 at various radio frequencies have delayed maxima at low frequencies, and the flare of 1998 was accompanied by the birth of a new superluminal component. __________ Translated from Astrofizika, Vol. 50, No. 3, pp. 325–334 (August 2007).  相似文献   

11.
This issue of AN contains the proceedings of the Special Colloquium “European Astronomy in the 20th Century”, which formed part of the JENAM (2001) conference in Munich, Germany. Subjects covered are the history of γ‐ray and radio astronomy, extragalactic research and compact objects, new media, southern observatories and ESO, as well as some archaeoastronomical questions. Some biographic sketches of individual European astronomers are also given.  相似文献   

12.
The paper refers to the current status of asteroid hazard in Russia and abroad. The authors emphasize the relevance of a sober assessment of its real state and specific circumstances working from the principle of reasonable sufficiency. The paper presents a practical approach to the asteroid hazard problem. It consists of a proposal for a mission to the Apophis asteroid and to define the main parameters of this hazardous celestial body. The article also considers how the spacecraft would look, as well as its mission profile for the period of 2012–2014.  相似文献   

13.
Results of a survey of instrumentation and detector systems, either currently deployed or planned for use at telescopes larger than 3.5 m, in ground based observatories world-wide, are presented. This survey revealed a number of instrumentation design trends at optical, near, and mid-infrared wavelengths. Some of the most prominent trends include the development of vastly larger optical detector systems (> 109 pixels) than anything built to date, and the frequent use of mosaics of near-infrared detectors – something that was quite rare only a decade ago in astronomy. Some future science applications for detectors are then explored, in an attempt to build a bridge between current detectors and what will be needed to support the research ambitions of astronomers in the future.  相似文献   

14.
BIMA SONG is a systematic imaging study of the 3 mm CO J = 1 → 0molecular emission within the centres and discs of 44 nearby spiral galaxies on size scales of a few hundred parsecs (6-9"). The overall goal of the survey is to study the role of molecular gas in the evolution of spiral galaxies. To this end, BIMA SONG addresses 1) the distribution and physical conditions of the molecular gas in galactic discs and its relation to star formation, 2) the effects of a stellar bar on the kinematics of molecular gas, including the possible inflow of gas along a bar, and 3) the distribution and role of molecular gas in the central few hundred parsecs of active and quiescent galaxies. The source list includes all (except M33and M31) 44 galaxies of Hubble types Sa–Sd, with declinations δ >−20°, visual magnitudes B < 11.0, velocities v hel <2000 km s-1, and inclinations i < 70°. Beyond the specific scientific questions we will address, this survey will provide a unique database for astronomers who study galaxies at all wavelengths. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

15.
M 1–92 is a very well studied bipolar pPN that can be considered an archetype of this type of sources; it shows a clear axial symmetry, along with the kinematics characteristic of this class of envelopes around post-AGB stars. We performed sub-arcsecond resolution observations of the J=2–1 rotational line of 13CO in M 1–92 with the new extended configurations of the IRAM Plateau de Bure interferometer, for studying the morphology and velocity field of the molecular gas better in the nebula, particularly in its central parts. We found that the equatorial structure dividing the two lobes is a thin flat disk, which expands radially with a velocity proportional to the distance to the central stellar system. The kinetic age of this equatorial flow is very similar to that measured in the two lobes, suggesting that the whole structure was formed as a result of a single event some 1200 yr ago, after which the nebula reached an expansion velocity field with axial symmetry. The small widths and velocity dispersion in the gas forming the lobe walls confirm that the acceleration responsible for the nebular shape could not last more than 100–120 yr. In view of the similarity to η Car, we speculate on the possibility that the whole nebula was formed as a result of a magneto-rotational explosion in a common-envelope system. The study of the possible importance of this mechanism in the context of global PNe and pPNe reshaping should be one on the fields in which future ALMA observations will make a crucial contribution. Based on observations carried out with the IRAM Plateau de Bure Interferometer. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain).  相似文献   

16.
This article is devoted to the Pulkovo astronomer, Prof. Aleksandr Nikolaevich Deich (Deutsch) (1899-1986), on the 110-th anniversary of his birth. Deich is known as the founder of the Pulkovo program for observing stars with invisible companions, as well as for his research on the star 61 Cyg, which was suspected, in his time, of having invisible companions with the masses of planets. Astrometric observations on the long focus astrograph and searches for exoplanets of nearby stars are reviewed. Modern methods of searching for exoplanets are summarized briefly. Instrument designs proposed by astronomers at Kharkiv (Scientific Research Institute of Astronomy at Kharkiv National University, NIIA KhNU) and Kazan (Institute of Astronomy, Kazan State University, AO KGU) for use in the search for low-mass dark components of stars are discussed. Examples are given of confirmations of invisible companions of stars which were first discovered by observation. A number of theoretical results on this topic from Kharkiv National University (Scientific Research Institute of Astronomy at Kharkiv and the Dept. of Astronomy) are noted.  相似文献   

17.
The impact of the Struve astronomical dynasty on the development of astronomy in Ukraine in the 19th–20th centuries is studied. First of all, the role of F.G.W. Struve and O.V. Struve in the formation of astronomical research programs at the observatories at the Kharkiv, Kyiv, Odesa, and Mykolayiv, in equipping the observatories with instruments, in practical training of astronomers as well as in the organization of astronomy-geodetic expeditions (19th century). Particular attention is paid to the activity of L.O. Struve as a director of the Astronomical observatory of Kharkiv University and his works conducted together with G.A. Shajn and B.P. Gerasimovich (20th century) as well as to the impact of his scientific and public activity, including one he made as a President of IAC, on the development of astronomy in the Soviet Union and Ukraine. A range of important documents from the archives of Russian Academy of Sciences, Institute of astronomy and State Archive of Ukraine are cited. The article was translated by the authors.  相似文献   

18.
At the First International Conference on Comet Hale–Bopp(Canaries, 1998) many astronomers agreed with the value of theperiod of axial rotation of its nucleus, which was obtained byobservers by a comparison of the two sequential patterns of thedust arcs. It was noted that the pattern had been repeated each∼12 hours. The value 11.35h was taken as the periodof axial rotation. However, alternative periods of 4 and 8 days havealso been suggested. The possible reasons for thisdiscrepancy are discussed. It is shown that a short period could be obtained by a misidentification of the same arc on twosequential images and, as a result, an overestimate of theradial velocity of dust in the arcs. To obtain the half day period one must take the projected velocity of the arc ∼ 1.6 km/s,which exceeds the H2O gas expansion velocity. If one takes a lower expansion velocity a longer period would be obtained.  相似文献   

19.
In this paper, we present the design of a high resolution Chirp Transform Spectrometer (CTS) which is part of the GREAT (German REceiver for Astronomy at Terahertz frequencies) instrument onboard SOFIA, the Stratospheric Observatory For Infrared Astronomy. The new spectrometer will provide unique spectral resolving power and linearity response, since the analog Fourier transform performed by the CTS spectrometer was improved through a new design, that we call “Adaptive Digital Chirp Processor (ADCP)”. The principle behind the ADCP consists on digitally generating the dispersive signal which adapts to the compressor dispersive properties, achieving maximum spectral resolution and higher dynamic range. Excellent test results have been obtained such as a white noise dynamic range of 30 dB, and a spectral resolution (FWHM) of 41.68 kHz which would mean if analyzing signals with the high frequency band receiver on the GREAT instrument (4.7 THz) a spectral resolving power (λ/Δ λ) higher than 108.  相似文献   

20.
We present scientific program construction principles and a time allocation scheme developed for the World Space Observatory—Ultraviolet (WSO-UV) mission, which is an international space observatory for observation in UV spectral range 100–300 nm. The WSO-UV consists of a 1.7 m aperture telescope with instrumentation designed to carry out high resolution spectroscopy, long-slit low resolution spectroscopy and direct sky imaging. The WSO-UV Ground Segment is under development by Spain and Russia. They will coordinate the Mission and Science Operations and provide the satellite tracking stations for the project.  相似文献   

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