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Space Science Reviews - Our awareness of the facts on Algol systems, arising from both statistical evidence and examination of particular examples, is presented. The statistical information derives... 相似文献
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Edwin Budding 《Space Science Reviews》1989,49(3-4):205-218
Our awareness of the facts on Algol systems, arising from both statistical evidence and examination of particular examples, is presented. The statistical information derives from the author's recent catalogue of Algol-type candidate stars. The particular cases of R Ara and W Cru are considered. The presence of undiscerned background factors in these systems exemplify persistent threats to the confidence we place on parameter sets characterising any models we may form of such objects. 相似文献
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The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) on the New Horizons Mission
Ralph L. McNutt Jr. Stefano A. Livi Reid S. Gurnee Matthew E. Hill Kim A. Cooper G. Bruce Andrews Edwin P. Keath Stamatios M. Krimigis Donald G. Mitchell Barry Tossman Fran Bagenal John D. Boldt Walter Bradley William S. Devereux George C. Ho Stephen E. Jaskulek Thomas W. LeFevere Horace Malcom Geoffrey A. Marcus John R. Hayes G. Ty Moore Mark E. Perry Bruce D. Williams Paul Wilson IV Lawrence E. Brown Martha B. Kusterer Jon D. Vandegriff 《Space Science Reviews》2008,140(1-4):315-385
The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) comprises the hardware and accompanying science investigation on the New Horizons spacecraft to measure pick-up ions from Pluto’s outgassing atmosphere. To the extent that Pluto retains its characteristics similar to those of a “heavy comet” as detected in stellar occultations since the early 1980s, these measurements will characterize the neutral atmosphere of Pluto while providing a consistency check on the atmospheric escape rate at the encounter epoch with that deduced from the atmospheric structure at lower altitudes by the ALICE, REX, and SWAP experiments on New Horizons. In addition, PEPSSI will characterize any extended ionosphere and solar wind interaction while also characterizing the energetic particle environment of Pluto, Charon, and their associated system. First proposed for development for the Pluto Express mission in September 1993, what became the PEPSSI instrument went through a number of development stages to meet the requirements of such an instrument for a mission to Pluto while minimizing the required spacecraft resources. The PEPSSI instrument provides for measurements of ions (with compositional information) and electrons from 10 s of keV to ~1 MeV in a 160°×12° fan-shaped beam in six sectors for 1.5 kg and ~2.5 W. 相似文献
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Vladimir Pletser Pierre Emmanuel Paulis Edwin Loosveldt Dominique Gering Mireille Body Robert Schewijck 《Acta Astronautica》2005,57(12):910-919
Since 1984, the European Space Agency (ESA) has organized 30 aircraft parabolic flight campaigns in the frame of its Microgravity Programme to perform short duration scientific and technological experiments. On each campaign, ESA invites journalists to report to the general public on the research work conducted in weightlessness. A new initiative was launched in 2000 with the introduction of pedagogical experiments aiming at educating youngsters and the general public on weightlessness effects. In November 2000, four secondary school teachers detached to the Euro Space Center (ESC) participated in the 29th ESA campaign. The ESC in Belgium provides recreational and educational activities for the general public and organizes space classes targeted at primary and secondary school pupils. The four teachers performed simple experiments with gyroscopes, yo-yos, magnetic balls, pendulum and food to explain their different behaviour in weightlessness, to show characteristics and possibilities of the microgravity environment and the difficulties that astronauts encounter in their daily life in orbit. 相似文献
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This paper explores concepts which apply emerging ground support technology (GST) to the rapid turnaround of tactical aircraft. This technology has the potential to reduce manpower requirements for ground servicing, increase sortie generation rates and expose fewer ground personnel to the lethal agents anticipated during biochemical warfare. The near term approach examines automated systems for refueling and rearming tactical aircraft assuming the returning aircraft suffer no disabling malfunctions or battle damage. In the far term, it is proposed that additional maintenance and servicing functions be performed by GST systems. Consideration is given to linking diagnostic computers on tactical aircraft with future robotic systems for direct repair and maintenance. It is concluded that GST systems, including robotics, provide the opportunity for revolutionary changes in aircraft servicing and maintenance and provide a viable option for generating sorties during and immediately following biochemical attack. 相似文献
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Kenneth P. Klaasen Brian Carcich Gemma Carcich Edwin J. Grayzeck Stephanie Mclaughlin 《Space Science Reviews》2005,117(1-2):335-372
A comprehensive observational sequence using the Deep Impact (DI) spacecraft instruments (consisting of cameras with two different
focal lengths and an infrared spectrometer) will yield data that will permit characterization of the nucleus and coma of comet
Tempel 1, both before and after impact by the DI Impactor. Within the constraints of the mission system, the planned data
return has been optimized. A subset of the most valuable data is planned for return in near-real time to ensure that the DI
mission success criteria will be met even if the spacecraft should not survive the comet’s closest approach. The remaining
prime science data will be played back during the first day after the closest approach. The flight data set will include approach
observations spanning the 60 days prior to encounter, pre-impact data to characterize the comet at high resolution just prior
to impact, photos from the Impactor as it plunges toward the nucleus surface (including resolutions exceeding 1 m), sub-second
time sampling of the impact event itself from the Flyby spacecraft, monitoring of the crater formation process and ejecta
outflow for over 10 min after impact, observations of the interior of the fully formed crater at spatial resolutions down
to a few meters, and high-phase lookback observations of the nucleus and coma for 60 h after closest approach. An inflight
calibration data set to accurately characterize the instruments’ performance is also planned. A ground data processing pipeline
is under development at Cornell University that will efficiently convert the raw flight data files into calibrated images
and spectral maps as well as produce validated archival data sets for delivery to NASA’s Planetary Data System within 6 months
after the Earth receipt for use by researchers world-wide. 相似文献
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Existing and planned optical telescopes and surveys can detect artificially illuminated objects, comparable in total brightness to a major terrestrial city, at the outskirts of the Solar System. Orbital parameters of Kuiper belt objects (KBOs) are routinely measured to exquisite precisions of<10(-3). Here, we propose to measure the variation of the observed flux F from such objects as a function of their changing orbital distances D. Sunlight-illuminated objects will show a logarithmic slope α ≡ (d log F/d log D)=-4, whereas artificially illuminated objects should exhibit α=-2. The proposed Large Synoptic Survey Telescope (LSST) and other planned surveys will provide superb data and allow measurement of α for thousands of KBOs. If objects with α=-2 are found, follow-up observations could measure their spectra to determine whether they are illuminated by artificial lighting. The search can be extended beyond the Solar System with future generations of telescopes on the ground and in space that would have the capacity to detect phase modulation due to very strong artificial illumination on the nightside of planets as they orbit their parent stars. 相似文献
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The Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) on the New Horizons Mission
Ralph L. McNutt Jr. Stefano A. Livi Reid S. Gurnee Matthew E. Hill Kim A. Cooper G. Bruce Andrews Edwin P. Keath Stamatios M. Krimigis Donald G. Mitchell Barry Tossman Fran Bagenal John D. Boldt Walter Bradley William S. Devereux George C. Ho Stephen E. Jaskulek Thomas W. LeFevere Horace Malcom Geoffrey A. Marcus John R. Hayes G. Ty Moore Nikolaos P. Paschalidis Mark E. Perry Bruce D. Williams Paul Wilson IV Lawrence E. Brown Martha B. Kusterer Jon D. Vandegriff 《Space Science Reviews》2009,145(3-4):381-381