排序方式: 共有41条查询结果,搜索用时 140 毫秒
31.
Alberto Adriani Gianrico Filacchione Tatiana Di Iorio Diego Turrini Raffaella Noschese Andrea Cicchetti Davide Grassi Alessandro Mura Giuseppe Sindoni Massimo Zambelli Giuseppe Piccioni Maria T. Capria Federico Tosi Roberto Orosei Bianca M. Dinelli Maria L. Moriconi Elio Roncon Jonathan I. Lunine Heidi N. Becker Alessadro Bini Alessandra Barbis Luciano Calamai Claudio Pasqui Stefano Nencioni Maurizio Rossi Marco Lastri Roberto Formaro Angelo Olivieri 《Space Science Reviews》2017,213(1-4):393-446
JIRAM is an imager/spectrometer on board the Juno spacecraft bound for a polar orbit around Jupiter. JIRAM is composed of IR imager and spectrometer channels. Its scientific goals are to explore the Jovian aurorae and the planet’s atmospheric structure, dynamics and composition. This paper explains the characteristics and functionalities of the instrument and reports on the results of ground calibrations. It discusses the main subsystems to the extent needed to understand how the instrument is sequenced and used, the purpose of the calibrations necessary to determine instrument performance, the process for generating the commanding sequences, the main elements of the observational strategy, and the format of the scientific data that JIRAM will produce. 相似文献
32.
Roberto Susino Alessandro Bemporad Sergio Dolei Angelos Vourlidas 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
We study the 3-D kinematics of a Coronal Mass Ejection (CME) using data acquired by the LASCO C2 and UVCS instruments on board SOHO, and the COR1 coronagraphs and EUVI telescopes on board STEREO. The event, which occurred on May 20, 2007, was a partial-halo CME associated with a prominence eruption. This is the first CME studied with UVCS data that occurred in the STEREO era. The longitudinal angle between the STEREO spacecrafts was ∼7.7° at that time, and this allowed us to reconstruct via triangulation technique the 3-D trajectory of the erupting prominence observed by STEREO/EUVI. Information on the 3-D expansion of the CME provided by STEREO/COR1 data have been combined with spectroscopic observations by SOHO/UVCS. First results presented here show that line-of-sight velocities derived from spectroscopic data are not fully in agreement with those previously derived via triangulation technique, thus pointing out possible limitations of this technique. 相似文献
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The Juno Gravity Science Instrument 总被引:1,自引:0,他引:1
Sami W. Asmar Scott J. Bolton Dustin R. Buccino Timothy P. Cornish William M. Folkner Roberto Formaro Luciano Iess Andre P. Jongeling Dorothy K. Lewis Anthony P. Mittskus Ryan Mukai Lorenzo Simone 《Space Science Reviews》2017,213(1-4):205-218
The Juno mission’s primary science objectives include the investigation of Jupiter interior structure via the determination of its gravitational field. Juno will provide more accurate determination of Jupiter’s gravity harmonics that will provide new constraints on interior structure models. Juno will also measure the gravitational response from tides raised on Jupiter by Galilean satellites. This is accomplished by utilizing Gravity Science instrumentation to support measurements of the Doppler shift of the Juno radio signal by NASA’s Deep Space Network at two radio frequencies. The Doppler data measure the changes in the spacecraft velocity in the direction to Earth caused by the Jupiter gravity field. Doppler measurements at X-band (\(\sim 8\) GHz) are supported by the spacecraft telecommunications subsystem for command and telemetry and are used for spacecraft navigation as well as Gravity Science. The spacecraft also includes a Ka-band (\(\sim 32\) GHz) translator and amplifier specifically for the Gravity Science investigation contributed by the Italian Space Agency. The use of two radio frequencies allows for improved accuracy by removal of noise due to charged particles along the radio signal path. 相似文献
35.
Emilie Habart Malcolm Walmsley Laurent Verstraete Stephanie Cazaux Roberto Maiolino Pierre Cox Francois Boulanger Guillaume Pineau Des Forêts 《Space Science Reviews》2005,119(1-4):71-91
Observations of H2 line emission in galactic and extragalactic environments obtained with the Infrared Space Observatory (ISO) are reviewed.
The diagnostic capability of H2 observations is illustrated. We discuss what one has learned about such diverse astrophysical sources as photon-dominated
regions, shocks, young stellar objects, planetary nebulae and starburst galaxies from ISO observations of H2 emission. In this context, we emphasise use of measured H2 line intensities to infer important physical quantities such as the gas temperature, gas density and radiation field and
we discuss the different possible excitation mechanisms of H2. We also briefly consider future prospects for observation of H2 from space and from the ground.
Based on observations with ISO, an ESA project with instruments funded by ESA Member States (especially the PI countries:
France, Germany, The Netherlands, and the United Kingdom), and with the participation of ISAS and NASA. 相似文献
36.
Lucia Abbo Ester Antonucci Zoran Mikić Jon A. Linker Pete Riley Roberto Lionello 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
The study concerns the streamer belt observed at high spectral resolution during the minimum of solar cycle 23 with the Ultraviolet Coronagraph Spectrometer (UVCS) onboard SOHO. On the basis of a spectroscopic analysis of the O VI doublet, the solar wind plasma parameters are inferred in the extended corona. The analysis accounts for the coronal magnetic topology, extrapolated through a 3D magneto-hydrodynamic model, in order to define the streamer boundary and to analyse the edges of coronal holes. The results of the analysis allow an accurate identification of the source regions of the slow coronal wind that are confirmed to be along the streamer boundary in the open magnetic field region. 相似文献
37.
Optimising filtering of two-line element sets to increase re-entry prediction accuracy for GTO objects 总被引:1,自引:0,他引:1
Aleksander A. Lidtke David J. Gondelach Roberto Armellin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(3):1289-1317
Predicting re-entry epoch of space objects enables managing the risk to ground population. Predictions are particularly difficult for objects in highly-elliptical orbits, and important for objects with components that can survive re-entry, e.g. rocket bodies (R/Bs). This paper presents a methodology to filter two-line element sets (TLEs) to facilitate accurate re-entry prediction of such objects. Difficulties in using TLEs for precise analyses are highlighted and a set of filters that identifies erroneous element sets is developed. The filter settings are optimised using an artificially generated TLE time series. Optimisation results are verified on real TLEs by analysing the automatically found outliers for exemplar R/Bs. Based on a study of 96 historical re-entries, it is shown that TLE filtering is necessary on all orbital elements that are being used in a given analysis in order to avoid considerably inaccurate results. 相似文献
38.
Implementation of an ESA delta-DOR capability 总被引:2,自引:0,他引:2
Nick James Ricard Abello Marco Lanucara Mattia Mercolino Roberto Madd 《Acta Astronautica》2009,64(11-12):1041-1049
This paper describes the implementation of delta-DOR (delta-differential one-way ranging) receivers within the ESA Deep Space ground station network. Delta-DOR provides very accurate plane-of-sky measurements of spacecraft position which complement existing line-of-sight ranging and Doppler measurements. We discuss how this technique has been adapted and implemented at the two ESA deep-space ground stations using existing equipment and infrastructure. These new capabilities were added by writing new software modules for the standard ESA digital receiver (the intermediate frequency modem system—IFMS). With these upgrades the receiver has the ability to record accurately timetagged signals from up to eight IF sub-channels. These sub-channels can have bandwidths of 50 kHz–2 MHz with a sample quantization of 1–16 bits per component. The IF samples are stored locally for subsequent retrieval over a WAN by the correlator facility at ESOC. 相似文献
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Alisson Dal Lago Walter D. Gonzalez Aline De Lucas Carlos Roberto Braga Lucas Ramos Vieira Tardelli Ronan Coelho Stekel Marlos Rockenbach 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
In this work, we present a study of the coronal mass ejection (CME) dynamics using LASCO coronagraph observations combined with in-situ ACE plasma and magnetic field data, covering a continuous period of time from January 1997 to April 2001, complemented by few extreme events observed in 2001 and 2003. We show, for the first time, that the CME expansion speed correlates very well with the travel time to 1 AU of the interplanetary ejecta (or ICMEs) associated with the CMEs, as well as with their preceding shocks. The events analyzed in this work are a subset of the events studied in Schwenn et al. (2005), from which only the CMEs associated with interplanetary ejecta (ICMEs) were selected. Three models to predict CME travel time to Earth, two proposed by Gopalswamy et al. (2001) and one by Schwenn et al. (2005), were used to characterize the dynamical behavior of this set of events. Extreme events occurred in 2001 and 2003 were used to test the prediction capability of the models regarding CMEs with very high LASCO C3 speeds. 相似文献