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821.
Laura I. Fernández Amalia M. Meza Ana G. Elías 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The quasi-biennial oscillation, QBO, a well known periodicity in the equatorial stratospheric zonal winds, is also found in ionospheric parameters and in solar and geomagnetic activity indices. Many authors speculated about the link between the QBO in solar and geomagnetic activity and the QBO in atmospheric parameters. In this work we analyze the presence of the QBO in the ionosphere using the Vertical Total Electron Content (VTEC) values obtained from Global Navigation Satellite System (GNSS) measurements during the period 1999–2012. In particular, we used IONEX files, i.e. the International GNSS Service (IGS) ionospheric products. IONEX provide VTEC values around the world at 2-h intervals. From these data we compute global and zonal averages of VTEC at different local times at mid and equatorial geomagnetic latitudes. VTEC and Extreme Ultra Violet (EUV) solar flux time series are analyzed using a wavelet multi resolution analysis. In all cases the QBO is detected among other expected periodicities. 相似文献
822.
I.P. Gabis 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Equatorial total column ozone variations with quasi-biennial periodicity are described by paying attention to their coupling with the quasi-biennial oscillation (QBO) of zonal wind in equatorial stratosphere. Analysis is made for the 35-year time interval from 1978 to 2013 using the zonal mean total ozone (TOZ) data in latitude band from 5° S to 5° N derived from satellite measurements by means of Total Ozone Mapping Spectrometer (TOMS) and Ozone Monitoring Instrument (OMI). The study was performed using strong seasonal regularities of the wind QBO and the discrete variation of the QBO-period revealed earlier. The forecast of the wind QBO evolution made in Gabis (2012) is fully justified. The comparison between predicted and actually observed changes of the height wind structure shows the prominent accordance, which confirms the forecast validity. It is shown that variations of deseasonalized TOZ are in strong coupling with changes of equatorial wind QBO that coincides with the numerous previous researches. However our results contradict the assumption about quite complicated ozone response in the equatorial region due to continuously varying with time relationship between annual and quasi-biennial cycles and irregularly variable wind QBO-period. The total ozone changes actually observed clearly corresponds to the mean ozone variations calculated for different QBO scenarios and aligned according to the sequence of QBO scenarios already occurred in fact. This close association indicates the possibility of forecasting the equatorial total ozone QBO based on the predicted wind QBO. 相似文献
823.
P. R. Christensen V. E. Hamilton G. L. Mehall D. Pelham W. O’Donnell S. Anwar H. Bowles S. Chase J. Fahlgren Z. Farkas T. Fisher O. James I. Kubik I. Lazbin M. Miner M. Rassas L. Schulze K. Shamordola T. Tourville G. West R. Woodward D. Lauretta 《Space Science Reviews》2018,214(5):87
The OSIRIS-REx Thermal Emission Spectrometer (OTES) will provide remote measurements of mineralogy and thermophysical properties of Bennu to map its surface, help select the OSIRIS-REx sampling site, and investigate the Yarkovsky effect. OTES is a Fourier Transform spectrometer covering the spectral range 5.71–100 μm (\(1750\mbox{--}100~\mbox{cm}^{-1}\)) with a spectral sample interval of \(8.66~\mbox{cm}^{-1}\) and a 6.5-mrad field of view. The OTES telescope is a 15.2-cm diameter Cassegrain telescope that feeds a flat-plate Michelson moving mirror mounted on a linear voice-coil motor assembly. A single uncooled deuterated l-alanine doped triglycine sulfate (DLATGS) pyroelectric detector is used to sample the interferogram every two seconds. Redundant ~0.855 μm laser diodes are used in a metrology interferometer to provide precise moving mirror control and IR sampling at 772 Hz. The beamsplitter is a 38-mm diameter, 1-mm thick chemical vapor deposited diamond with an antireflection microstructure to minimize surface reflection. An internal calibration cone blackbody target provides radiometric calibration. The radiometric precision in a single spectrum is \(\leq2.2 \times 10^{-8}~\mbox{W}\,\mbox{cm}^{-2}\,\mbox{sr} ^{-1}/\mbox{cm}^{-1}\) between 300 and \(1350~\mbox{cm}^{-1}\). The absolute integrated radiance error is \(<1\%\) for scene temperatures ranging from 150 to 380 K. The overall OTES envelope size is \(37.5 \times 28.9 \times 52.2~\mbox{cm}\), and the mass is 6.27 kg. The power consumption is 10.8 W average. OTES was developed by Arizona State University with Moog Broad Reach developing the electronics. OTES was integrated, tested, and radiometrically calibrated on the Arizona State University campus in Tempe, AZ. 相似文献
824.
825.
Solar proton events recorded in the stratosphere during cosmic ray balloon observations in 1957–2008
G.A. Bazilevskaya V.S. MakhmutovY.I. Stozhkov A.K. SvirzhevskayaN.S. Svirzhevsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Long-term balloon observations have been performed by the Lebedev Physical Institute since 1957 up to the present time. The observations are taken several times a week at the polar and mid latitudes and allow us to study dynamics of galactic and solar cosmic ray as well as secondary particle fluxes in the atmosphere and in the near-Earth space. Solar energetic particles (120) – mostly protons – (SEP) events with >100 MeV proton intensity above 1 cm−2 s−1 s−1 were recorded during 1958–2006. Before the advent of the SEP monitoring on spacecraft these results constituted the only homogeneous series of >100 MeV SEP events. The SEP intensities and energy spectra inferred from the Lebedev Physical Institute observations are consistent with the results taken in the adjacent energy intervals by the spacecraft and neutron monitors. Joint consideration of the SEP events series recorded by balloons and by neutron monitors during solar cycles 20–23 makes it possible to restore the probable number of events in solar cycle 19, which was not properly covered by observations. Some correlation was found between duration of SEP event production in a solar cycle and sunspot cycle characteristics. 相似文献
826.
The International Institute of Space Commerce (IISC) held a workshop on the influence of the financial crisis on the space sector in Douglas, Isle of Man from 18 to 19 November 2009. A number of experts presented their views on this topic. A summary of their generally upbeat findings are presented below. 相似文献
827.
An analysis of enhancements in the fluxes of electrons with energies above 300 keV registered onboard of the Coronas-F satellite in the polar regions at the boundary of the outer radiation belt is performed. Cases are revealed when the increases
in question were observed consequently during multiple crossings of the outer radiation belt boundary. Localization of the
revealed events relative to the auroral oval using the data of almost simultaneous observations of electrons with energies
of 0.1–10 keV on the Meteor-3M satellite and OVATION model is studied. It is shown that almost all studied increases in relativistic electrons are localized
at latitudes of the auroral oval. Various mechanisms which could cause the observed increases are discussed, as well as a
possibility of formation of local traps of energetic particles in the high-latitude magnetosphere. 相似文献
828.
A. V. Rodin N. A. Evdokimova R. O. Kuzmin A. A. Fedorova O. I. Korablev J. -P. Bibring 《Cosmic Research》2010,48(2):150-156
Channel C of the orbital hyperspectrometer OMEGA onboard Mars Express spacecraft has delivered data on the distribution and seasonal variability of water ice spectral features at 1.25, 1.5, 2.0
μm, based on which one may conclude about the thickness of ice coverage and microstructure of the upper, optically active
ice layer on the Martian surface. Data covering polar regions during spring-to-summer periods of both hemispheres have been
analyzed. Microstructure of the North polar cap, as well as the residual frost deposits of the seasonal South polar cap, have
revealed remarkable zonal variations with regularly located maxima. Based on the comparison with the atmospheric general circulation
model results, it has been proposed that these variations result from the impact of mesoscale inertial waves in the circumpolar
vortex on water exchange processes between the atmosphere and planetary surface. 相似文献
829.
I. S. Akhmed’yanov 《Russian Aeronautics (Iz VUZ)》2010,53(1):102-107
The application of the numerical quadrature method to analyzing the shells of revolution under reversely symmetrical loading
is considered. 相似文献
830.