SCALES FOR DETERMINING SLOPE FROM TOPOGRAPHIC MAPS     

Norman J. W. Thrower  Ronald U. Cooke 《The Professional geographer》1968,20(3):181-186

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New 1982 — 1990 photometry of λ Andromedae and its 11-year cycle     

Douglas S. Hall  Gregory W. Henry  Dietmar Böhme  Peter A. Brooks  Sandy Chang  Ales Dolzan  George L. Fortier  Robert E. Fried  Russell M. Genet  Bruce S. Grim  James Hannon  Darrel B. Hoff  Kevin Krisciunas  Howard J. Landis  Howard P. Louth  Larry P. Lovell  Paul Nielsen  Bobby E. Powell  Harry D. Powell  Don Pray  Thomas R. Renner  Charles W. Rogers  Stephen Shervais  Douglas M. Slauson  Samuel Slote  Harold J. Stelzer  Arthur J. Stokes  Jack C. Troeger  Louis C. Turner  Norman F. Wasson  Kenneth W. Zeigler 《Journal of Astrophysics and Astronomy》1991,12(4):281-287

We present photoelectric photometry of λ And never before published, obtained between February 1982 and December 1990 at 29 different observatories. Then we combine it with all other photometry available to us (previously published, contained in the I.A.U. Commission 27 Archives, and obtained with the Vanderbilt 16-inch automatic telescope but not yet published), to yield a 14.8-year data base. Analysis reveals a long-term cycle in mean brightness, with a full range of 0^m.15 and a period of 11.4 ± 0.4 years. Because most of our new photometry was concentrated in the 1983-84 observing season, we analyze that one well-defined light curve with a two-spot model. Spot A keeps a 0^m.04 amplitude throughout four rotation cycles whereas the amplitude of spot B diminishes from 0^m.09 down almost to 0^m.03. The spot rotation periods were 55^d.9 ± 0^d.6 and 520^d.8 ± 1^d.0, respectively.  相似文献   

Strategy for Applying Neutrino Geophysics to the Earth Sciences Including Planetary Habitability     

Norman H. Sleep 《Earth, Moon, and Planets》2006,99(1-4):343-358

Antineutrino data constrain the concentrations of the heat producing elements U and Th as well as potentially the concentration of K. Interpretation is similar to but not homologous with gravity. Current geoneutrino physics efficiently asks simple questions taking advantage of what is already known about the Earth. A few measurements with some sites in the ocean basins will constrain the concentration of U and Th in the crust and mantle and whether the mantle is laterally heterogeneous. These results will allow Earth science arguments about the formation, chemistry, and dynamics of the Earth to be turned around and appraised. In particular, they will tell whether the Earth accreted its expected share of these elements from the solar nebula and how long radioactive heat will sustain active geological processes on the Earth. Both aspects are essential to evaluating the Earth as a common or rare habitable planet.  相似文献   

Helical magnetic fields associated with the relativistic jets of four BL Lac objects     

Denise C. Gabuzda  Éamonn Murray  Patrick Cronin 《Monthly notices of the Royal Astronomical Society》2004,351(4):L89-L93

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A Chandra observation of the interacting pair of galaxies NGC 4485/4490     

T. P. Roberts  R. S. Warwick  M. J. Ward  S. S. Murray 《Monthly notices of the Royal Astronomical Society》2002,337(2):677-692

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The NASA Astrophysics Data System: Free Access to the Astronomical Literature On-line and through Email     

Guenther Eichhorn  Alberto Accomazzi  Carolyn S. Grant  Michael J. Kurtz  Stephen S. Murray 《Astrophysics and Space Science》2002,282(1):299-340

The Astrophysics Data System (ADS) provides access to the astronomical literature through the World Wide Web. It is a NASA funded project and access to all the ADS services is free to everybody world-wide. The ADS Abstract Service allows the searching of four databases with abstracts in Astronomy, Instrumentation, Physics/Geophysics, and the LANL Preprints with a total of over 2.2 million references. The system also provides access to reference and citation information, links to on-line data, electronic journal articles, and other on-line information. The ADS Article Service contains the full articles for most of the astronomical literature back to volume 1. It contains the scanned pages of all the major journals (Astrophysical Journal, Astronomical Journal, Astronomy & Astrophysics, Monthly Notices of the Royal Astronomical Society, and Solar Physics), as well as most smaller journals back to volume 1.The ADS can be accessed through any web browser without signup or login. Alternatively an email interface is available that allows our users to execute queries via email and to retrieve scanned articles via email. This might be interesting for users on slow or unreliable links, since the email system will retry sending information automatically until the transfer is complete. There are now 9 mirror sites of the ADS available in different parts of the world to improve access. The ADS is available at: http://ads.harvard.edu This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Characterization of the Sukinda and Nausahi ultramafic complexes,Orissa, India by platinum-group element geochemistry     

Norman J Page  P.K Banerji  Joseph Haffty 《Precambrian Research》1985,30(1):27-41

Samples of 20 chromitite, 14 ultramafic and mafic rock, and 9 laterite and soil samples from the Precambrian Sukinda and Nausahi ultramafic complexes, Orissa, India were analyzed for platinum-group elements (PGE). The maximum concentrations are: palladium, 13 parts per billion (ppb); platinum, 120 ppb; rhodium, 21 ppb; iridium, 210 ppb; and ruthenium, 630 ppb. Comparison of chondrite-normalized ratios of PGE for the chromitite samples of lower Proterozoic to Archean age with similar data from Paleozoic and Mesozoic ophiolite complexes strongly implies that these complexes represent Precambrian analogs of ophiolite complexes. This finding is consistent with the geology and petrology of the Indian complexes and suggests that plate-tectonic and ocean basin developement models probably apply to some parts of Precambrian shield areas.  相似文献   

Pressure effects on martian crustal magnetization near large impact basins     

Gunther KLETETSCHKA  John E. P. CONNERNEY  Norman F. NESS  Mario H. ACU A 《Meteoritics & planetary science》2004,39(11):1839-1848

Abstract— Martian crust endured several large meteoroid impacts subsequent to the demise of an early global magnetic field. Shock pressures associated with these impacts demagnetized parts of the crust, to an extent determined by shock resistance of magnetic materials in the crust. Impacts that form large basins generate pressures in excess of 1 GPa within a few crater radii of their impact sites. Crustal materials near the surface experience significantly reduced impact pressure, which varies with depth and distance from the impact point. We present new demagnetization experiments on magnetite (Fe₃O₄), hematite (α‐Fe₂O₃), and titanohematite (Fe_2‐xTi_xO₃ where x <0.2). Our measurements show that pressures of ?1 GPa are sufficient to partially demagnetize all of these minerals. The efficiency of demagnetization by impact pressure is proportional to the logarithm of the minerals' magnetic coercivity. The impact pressure magnetic response from exsolved titanohematite samples is consistent with the magnetization decay near Prometheus impact basin and may point to an oxidized igneous rock in Terra Sirenum region at the time of acquisition of magnetic remanence. The remaining magnetic anomalies near large impact basins suggest moderate crustal coercivity. These anomalies point to titanomagnetite as a magnetic carrier and more reduced condition during crustal formation.  相似文献   

Forgotten coast,forgotten people: sustainable development and disproportionate impacts from Hurricane Michael in Gulf County,Florida     

Boda  Chad S.  Scown  Murray W.  Faran  Turaj 《Natural Hazards》2022,111(1):877-899

Natural Hazards - A central challenge for sustainable development is how societies are to avoid, minimize or address impacts from anthropogenic climate change. However, competing perspectives on...  相似文献   

An example of attenuation by wet snow on a radar dome     

Norman R. Donaldson 《大气与海洋》2013,51(4):699-711

Abstract

A case study of the degradation of weather radar data by the accretion of wet snow on a radar dome is presented as a precautionary example to radar users. During the ERICA field program in 1989, accumulated precipitation on the radome at Halifax, Nova Scotia, attenuated signal in a distinctive, pie‐shaped sector on the upwind side of the radar.  相似文献