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1.
Book reviewed in this article: Catalogue of Meteorites, Fifth Edition (Revised and Enlarged) by Monica M. Grady Extrasolar Planets: The Search for New Worlds by Stuart Clark The Moon: Resources, Future Development and Colonization by David Schrunk, Burton Sharpe, Bonnie Cooper and Madhu Thangavelu Rare Earth: Why Complex Life is Uncommon in the Universe by Peter D. Ward and Donald E. Brownlee  相似文献   

2.
Book reviewed in this article: Physics and Chemistry of the Solar System by John S. Lewis Craters, Cosmos, and Chronicles: A New Theory of Earth by Herbert R. Shaw  相似文献   

3.
Book reviewed in this article: After the First Three Minutes Theory of Thermoluminescence and Related Phenomena by Reuven Chen and Stephen W. S. McKeever. Impakt—Gefahr aus dem All: Das Ende der Zivilisation by Christian Koeberl. Traces of Catastrophe: A Handbook of Shock-Metamorphic Effects in Terrestrial Meteorite Impact Structures by Bevan M. French. The New Solar System, Fourth Edition edited by J. Kelly Beatty, Carolyn Collins Peterson, and Andrew Chaikin.  相似文献   

4.
Book reviewed in this article: New Cosmic Horizons by David Leverington. Chronology and Evolution of Mars edited by R. Kallenbach, J. Geiss and W. K. Hartmann. Higher than Everest: An Adventurer's Guide to the Solar System by Paul Hodge.  相似文献   

5.
Book reviewed in this article: Islands in the Sky: Bold New Ideas for Colonizing Space edited by Stanley Schmidt and Robert Zubrin Mineralogy Tutorials: Interactive Instruction on CD-ROM Annual Review of Earth and Planetary Sciences, Volume 24 edited by G. W. Wetherill, A. L. Albee and K. C. Burke. Discovering the Cosmos by R. C. Bless.  相似文献   

6.
Book Reviews     
Book reviewed in this article: Ripples in the Cosmos: A View Behind the Scenes of the New Cosmology by Michael Rowan-Robinson. Annual Review of Astronomy and Astrophysics edited by Geoffrey Burbidge, David Layzer, and Allan Sandage. Planetologie: Eine Einführung by Ludolf Schultz. Mars edited by Hugh H. Kieffer, Bruce M. Jakosky, Conway W. Snyder and Mildred S. Matthews.  相似文献   

7.
Book reviewed in this article: Tektite—Zeugen kosmischer Katastrophen by G. Heinen Dana's New Mineralogy—The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Eighth Edition edited by Richard V. Gaines;, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason and Abraham Rosenzweig Tektites, A Cosmic Paradox by Hal Povenmire and edited by John A. O'Keefe 'Silica ‘96’: Meeting on Libyan Desert Glass and Related Desert Events edited by Vincenzo de Michele  相似文献   

8.
Peter Rovithis 《Icarus》1973,20(4):507-510
New measurements of the Venus diameter in four wavelengths are presented. These measurements refer to phase angles between 92° and 145° completing those by other observers. No dependence on the wavelength of the diameter of the planet is found. The resulted value is : 16.86 ± 0.02 arcsec.  相似文献   

9.
New photoelectric UBVR observations of the early-type eclipsing variable V498 Cyg were carried out in 1999–2002. New moments of minima were obtained and the ephemeris of the binary was improved: Min I = HJD 2442633.3955(90) + 3.4848437(34)E. All observations were grouped into two seasons, 1999-2001 and 2002, according to the light curve shape. The light curves were solved by Lavrov’s direct method, and the photometric orbit elements were calculated. Our estimates of the fundamental parameters of the binary components allowed us to class them with the B1 III and B3 III stars. Judging from the distance modulus, proper motion, and age of the binary, it can be assigned to the physical members of the Cyg OB9 association.  相似文献   

10.
New results are shown for the possible long term evolution of the orbit of Enceladus perturbed by Dione in the 2:1 resonance in the planar elliptic restricted problem. The numerical integrations of the secular variation equations (Ferraz-Mello and Dvorak, 1986) yield different types of chaotic behaviour. We also studied the onset of chaos for this dynamical system. Additionally, some illustrative pictures of the whole phase trajectory show the complex structure of phase space.  相似文献   

11.
New strong non-spiralling-in gravitational wave (GW) source for LIGO/VIRGO detectors are proposed. Double ONe–Mg white dwarf mergers can produce strong gravitational waves with frequencies in the several hundreds Hz range. Such events can be followed by a Super Nova type Ia.  相似文献   

12.
New precise times of minimum light for several early-type eclipsing binaries were obtained at three observatories. The changes of period of the following measured binaries are discussed: V1182 Aql, LY Aur, SZ Cam, FZ CMa, QZ Car, LZ Cen, V606 Cen, AH Cep and TU~Mus.  相似文献   

13.
Spencer  John  Buie  Marc  Young  Leslie  Guo  Yanping  Stern  Alan 《Earth, Moon, and Planets》2003,92(1-4):483-491
Development of the New Horizons mission to Pluto and the Kuiper Belt is now fully funded by NASA (Stern and Spencer, this volume). If all goes well, New Horizons will be launched in January 2006, followed by a Jupiter gravity assist in 2007, with Pluto arrival expected in either 2015 or 2016, depending on the launch vehicle chosen. A backup launch date of early 2007, without a Jupiter flyby, would give a Pluto arrival in 2019 or 2020. In either case, a flyby of at least one Kuiper Belt object (KBO) is planned following the Pluto encounter, sometime before the spacecraft reaches a heliocentric distance of 50 AU, in 2021 or 2023 for the 2006 launch, and 2027 or 2029 for the 2007 launch. However, none of the almost 1000 currently-known KBOs will pass close enough to the spacecraft trajectory to be targeted by New Horizons, so the KBO flyby depends on finding a suitable target among the estimated 500,000 KBOs larger than 40 km in diameter. This paper discusses the issues involved in finding one or more KBO targets for New Horizons. The New Horizons team plans its own searches for mission KBOs but will welcome other U.S, or international team who wish to become involved in exchange for mission participation at the KBO.  相似文献   

14.
In recent decades, investigations of Pluto with up-to-date astronomical instruments yielded results that have been generally confirmed by the New Horizons mission. In 2006, in Prague, the General Assembly of the International Astronomical Union (IAU) reclassified Pluto as a member of the dwarf planet category according to the criteria defined by the IAU for the term “planet”. At the same time, interest in studies of Pluto was increasing, while the space investigations of Pluto were delayed. In 2006, the New Horizons Pluto spacecraft started its journey to Pluto. On July 14, 2015, the spacecraft, being in fly-by mode, made its closest approach to Pluto. The heterogeneities and properties of the surface and rarified atmosphere were investigated thoroughly. Due to the extreme remoteness of the spacecraft and the energy limitations, it will take 18 months to transmit the whole data volume. Along with the preliminary results of the New Horizons Pluto mission, this paper reviews the basics on Pluto and its moons acquired from the ground-based observations and with the Hubble Space Telescope (HST). There are only a few meteorite craters on the surfaces of Pluto and Charon, which distinctly marks them apart from such satellites of the giant planets as Ganymede and Callisto. The explanation is that the surface of Pluto is young: its age is estimated at less than 100 Myr. Ice glaciers of apparently a nitrogen nature were found. Nitrogen is also the main component of the atmosphere of Pluto. The planet demonstrates the signs of strong geologic activity, though the energy sources of these processes are unknown.  相似文献   

15.
The position of the satellite within the protonebula, the influence of the parent planet, particularly the relative effects of tidal (gravitational) as opposed to radiogenic (internal) heat generating processes, as well as the type of ice, exert a control on the evolutionary histories of the Jovian and Saturnian satellites. The landscapes of the moons are modified by surface deformational processes (tectonic activity derived from within the body) and externally derived cratering. The geological history of the Galilean satellites is deduced from surface stratigraphic successions of geological units. Io and Europa, with crater-free surfaces, are tectonically more advanced than crater-saturated Callisto.Two thermal-drive models are proposed based on: an expression for externally derived gravitational influences between two bodies; and internal heat generation via radiogenic decay (expressed by surface area/volume ratio). Both parameters, for the Galilean satellites, are plotted against an inferred product of tectonic processes — the age of the surface terrain. From these diagrams, the tectonic evolutionary state of the more distant Saturnian system are predicted. These moons are fitted into an evolutionary framework for the Solar System.Based on a paper presented at the 1985 Royal Astronomical Society of New Zealand Conference, Hamilton, New Zealand.  相似文献   

16.
Abstract— Recent estimates of the current rate of meteorite falls have been derived from camera network observations and from the statistics of the recovery of small fragments in Roosevelt County, New Mexico. The results are discordant. The integrated sky coverage for the camera data is an order of magnitude greater than the long exposure over small areas in New Mexico, yet the number of inferred events is comparable. We examine potential problems and find no effects other than random ones to bias the camera data. New data on the total number of suitable fireballs indicate that the flux from the camera network is already close to the upper limit imposed by the count of over 700 fireballs. By contrast, the calibration of the decay time for small fragments in New Mexico appears insecure and could account for a factor-of-three discrepancy. The large area of a typical strewn field relative to the small search areas is also a serious problem that remains uncalibrated. There are problems with the application of either the camera results or the New Mexico data to the statistics of recoveries in Antarctica since the Antarctic search areas are not free from the strewn-field problem. Since there is no evidence for a substantial change in the infall rate in intervals less than the ages of the collecting surfaces, we believe the camera network flux data remain the best estimate for the arrival rate of small meteorites on Earth.  相似文献   

17.

Book Review

Comets: a chronological history of observation, science, myth, and folkloreD. K. Yeomans, Wiley, New York and Chichester. i-x+485 pp., bibliography and index. Price: £25.00, US $35.00 (hardcover); ISBN 0-4-71-61011-9  相似文献   

18.
New ground-based BV RI CCD observations of the eclipsing binary systems NN Vir and YY CrB are analyzed and illustrated. New times of minima are given and new ephemerides are proposed. The light curves are analyzed with the Wilson-Devinney light curve synthesis code and new geometric and photometric elements are derived. These elements are used together with the available spectroscopic data to compute absolute elements. The evolutionary status of each system is studied by means of mass-radius diagrams. The systems NN Vir and YY CrB are found to be A-type and W-type W UMa systems, respectively.  相似文献   

19.
Abstract— A meteoritic origin was proposed for the New Quebec Crater in 1949 on the basis of an aerial photograph showing its unique circularity and raised rim amid Precambrian gneisses of the Canadian Shield. At that time, only those few craters associated with meteorites were generally accepted as of impact origin. When the earliest field expeditions failed to find meteorites or impact products, two leading meteoriticists, Frederick C. Leonard and Lincoln LaPaz, cited the “Chubb” Crater as a flagrant example for which claims of meteoritic origin were advanced without valid proof. They also listed the Lake Bosumtwi Crater in Ashanti (now Ghana) among crater-like features, clearly of non-meteoritic origin, misidentified as meteorite craters. Controversy over the origin these two craters continued for decades. In Part I of this paper, we trace the investigations that led to the current acceptance of New Quebec as an authentic impact crater. We note that, for reasons that are not entirely clear, a meteoritic origin for the New Quebec Crater achieved wider acceptance at an earlier date than for the Lake Bosumtwi Crater, where petrographic and chemical evidence is more abundant and compelling. In Part II, we describe the petrography of two impact melt samples from the New Quebec Crater and present new evidence on the degrees of shock metamorphism affecting the accessory minerals: apatite, sphene, magnetite and zircon. Zircon, in particular, shows a range from euhedral grains with no signs of alteration to those decomposed to baddeleyite plus silica.  相似文献   

20.
New BVR light curves and a photometric analysis of the eclipsing binary star V1430 Aql are presented. The light curves were obtained at the Çanakkale Onsekiz Mart University Observatory in 2004. The light curves are generally those of detached eclipsing binaries, but there are large asymmetries between maxima. New BVR light curves were analysed with an ILOT procedure. Light curve asymmetries of the system were explained in terms of large dark starspots on the primary component. The primary star shows a long‐lived and quasi‐poloidal spot distribution with active longitudes in opposite hemispheres. Absolute parameters of the system were derived.We also discuss the evolution of the system: the components are likely to be pre‐main sequence stars, but a post‐main sequence stage cannot be ruled out. More observations are needed to decide this point. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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