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Conference paperDa Silva Curiel A, Meerman M, Liddle D, et al., 2003,
FRISBEE - A platform for a small satellite science swarms
, Pages: 3671-3678The FRISBEE multi-mission platform is presented, alongside the mission concept for SWARM (Space Weather Advanced Research Mission), a fleet of 30 or more microsatellites launched in groups of 5 and covering a range of local times and inclinations. The aim of this mission is to develop an understanding of the dynamic, global, and multiscale solar terrestrial interactions. The scientific payload is restricted to a dc magnetometer and electrostatic charged particle (ion and electron) analyser, providing both high time resolution and characterisation of collisionless plasma processes, together with a miniaturised radiation environment monitor, CEDEX-2, to measure total-ionising radiation dose and the higher energy protons and heavy ions associated with single-event-effect activity. The baseline satellite swarm can be launched in a variety of configurations and be augmented by future launches of identical satellites to provide greater coverage and density of measurement. The satellites require only loose formation control to ensure equal separation throughout the set of orbits defined in this document. The individual satellites are spin stabilized and each have a mass < 25 kg.
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Conference paperHodgson E, Sidgreaves R, Braham S, et al., 2003,
NASA has long recognized the advantages of providing improved information interfaces to EVA astronauts and has pursued this goal through a number of development programs over the past decade. None of these activities or parallel efforts in industry and academia has so far resulted in the development of an operational system to replace or augment the current extravehicular mobility unit (EMU) Display and Controls Module (DCM) display and cuff checklist. Recent advances in display, communications, and information processing technologies offer exciting new opportunities for EVA information interfaces that can better serve the needs of a variety of NASA missions. Hamilton Sundstrand Space Systems International (HSSSI) has been collaborating with Simon Fraser University and others on the NASA Haughton Mars Project and with researchers at the Massachusetts Institute of Technology (MIT), Boeing, and Symbol Technologies in investigating these possibilities. The objectives of this research so far have been to better understand the ways in which an improved information interface may be applied in a variety of mission settings and to refine the definition of system design requirements to best support those applications. Research efforts have combined the results of concept definition and mission requirements studies with experiments in pressurized spacesuits in the laboratory and in lower fidelity test-beds in field settings. Several promising approaches for the integration of highly capable information interfaces with EVA systems have evolved and have been evaluated in preliminary proof-of-concept tests. The results show considerable promise that an advanced information interface could be adapted to support near-term orbital EVA missions and could be evolved to provide robust support for future planetary exploration missions. Copyright © 2003 Hamilton Sundstrand Space Systems International, Inc.
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Journal articleJones GH, Balogh A, McComas DJ, et al., 2003, , ICARUS, Vol: 166, Pages: 297-310, ISSN: 0019-1035
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- Citations: 16
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Conference paperSandford MCW, Allan PM, Caldwell ME, et al., 2003, , 51st International Astronautical Congress, Publisher: PERGAMON-ELSEVIER SCIENCE LTD, Pages: 909-915, ISSN: 0094-5765
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- Citations: 5
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Journal articleMaynard NC, Ober DM, Burke WJ, et al., 2003, , ANNALES GEOPHYSICAE, Vol: 21, Pages: 2233-2258, ISSN: 0992-7689
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- Citations: 22
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Journal articleCui HL, Jin SP, Liu SL, et al., 2003, , CHINESE SCIENCE BULLETIN, Vol: 48, Pages: 2634-2639, ISSN: 1001-6538
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Journal articleSmith EJ, Marsden RG, Balogh A, et al., 2003, , SCIENCE, Vol: 302, Pages: 1165-1169, ISSN: 0036-8075
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- Citations: 61
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Journal articleJones GH, Balogh A, Russell CT, et al., 2003, , ASTROPHYSICAL JOURNAL, Vol: 597, Pages: L61-L64, ISSN: 0004-637X
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- Citations: 12
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Journal articleKivelson MG, Southwood DJ, 2003, , PLANETARY AND SPACE SCIENCE, Vol: 51, Pages: 891-898, ISSN: 0032-0633
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- Citations: 16
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Journal articleBrindley HE, Harries JE, 2003, , JOURNAL OF CLIMATE, Vol: 16, Pages: 3820-3833, ISSN: 0894-8755
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- Citations: 10
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Journal articleCheung ASC, Wong AL, Lo DHY, et al., 2003, , JOURNAL OF CHEMICAL PHYSICS, Vol: 119, Pages: 8373-8378, ISSN: 0021-9606
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- Citations: 9
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Journal articleBrindley HE, Allan RP, 2003, , Quarterly Journal of the Royal Meteorological Society, Vol: 129, Pages: 2971-2988, ISSN: 0035-9009
Using atmospheric profiles derived from the Hadley Centre atmosphere climate model version 3 (HadAM3) as input to a radiative transfer code, the sensitivity of the resolved spectrum of clear-sky outgoing long-wave radiation to both interannual and longer-term atmospheric variability has been analysed. A comparison of the simulated spectra with available observations from two satellite-based instruments indicates a reasonable match, although consistent differences are present. These may be explained by a combination of uncertainties in the atmospheric state, and in the relative calibration of the two instruments. Focusing on the simulations: if HadAM3 is forced by the observed sea surface temperature (SST) record alone, and long-term alterations in the well-mixed greenhouse gases are imposed in the radiance simulations, the changes seen within the major absorption bands are robust. Under a second scenario, where the effects of solar variability, volcanic aerosol, ozone changes and increases in the well-mixed greenhouse gases are also included in the forcing of HadAM3, the long-term profile changes tend to show an enhanced upper-tropospheric warming and low/mid-stratospheric cooling, with increased near-surface humidities compared to the SST-only case. However, the tropospheric response of the system, manifested in the spectral change pattern over the atmospheric window and water vapour bands, falls within the range of year-to-year variability.
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Journal articleCzaja A, 2003, , Quarterly Journal of the Royal Meteorological Society, Vol: 129, Pages: 2867-2878, ISSN: 0035-9009
A new diagnostic to investigate the role of ocean dynamics in midlatitude air-sea interactions is presented and tested against observations. It is based on the analysis of the time variability of the net ocean-to-atmosphere heat flux (F<inf>S</inf>). A hierarchy of air-sea interaction models indicate that, in the absence of ocean dynamics, the power spectrum of F<inf>S</inf> should be blue at time-scales longer than a threshold set by the late-winter mean mixed-layer thickness and the sensitivity of F<inf>S</inf> to sea surface temperature anomalies. Comparison of the predicted F<inf>S</inf> spectrum with observations over the North Atlantic shows a good agreement over the subpolar gyre where the deep ocean mixed layer combined with strong stochastic forcing allows large fluctuations in F<inf>S</inf> at decadal and longer time-scales. Discrepancies, however, arise over the Gulf Stream extension region. Here it is suggested that the observed variability of F<inf>S</inf> at time-scales longer than a decade is controlled by geostrophic ocean dynamics rather than local atmospheric forcing. The diagnostic appears to be a useful and simple tool to investigate the role of ocean dynamics in the upper-ocean heat budget. It is particularly well suited to the analysis of long simulations of coupled ocean-atmosphere models. One implication of the study for ocean-only numerical simulations is that one cannot specify externally the low-frequency variability of F<inf>S</inf>. The latter should only arise as a consequence of ocean dynamics.
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Journal articleBogdanov AT, Glassmeier KH, Musmann G, et al., 2003, , ANNALES GEOPHYSICAE, Vol: 21, Pages: 2043-2057, ISSN: 0992-7689
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- Citations: 9
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Journal articleCzaja A, 2003, , QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Vol: 129, Pages: 2867-2878, ISSN: 0035-9009
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- Citations: 3
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Journal articleZong QG, Fritz TA, Spence H, et al., 2003, , PLANETARY AND SPACE SCIENCE, Vol: 51, Pages: 821-830, ISSN: 0032-0633
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- Citations: 27
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Journal articleMazelle C, Meziane K, LeQu茅au D, et al., 2003, , PLANETARY AND SPACE SCIENCE, Vol: 51, Pages: 785-795, ISSN: 0032-0633
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- Citations: 90
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Journal articleBrindley HE, Allan RP, 2003, , QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Vol: 129, Pages: 2971-2988, ISSN: 0035-9009
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- Citations: 11
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Journal articleSanderson TR, Marsden RG, Tranquille C, et al., 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 15
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Journal articleDalla S, Balogh A, Krucker S, et al., 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 64
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Journal articleReisenfeld DB, Gosling JT, Forsyth RJ, et al., 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 44
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Journal articleHofer MY, Marsden RG, Sanderson TR, et al., 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 4
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Journal articleJones GH, Balogh A, Smith EJ, 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 35
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Journal articleRees A, Forsyth RJ, 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 10
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Journal articleLin NG, Kellogg PJ, MacDowall RJ, et al., 2003, , GEOPHYSICAL RESEARCH LETTERS, Vol: 30, ISSN: 0094-8276
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- Citations: 10
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Journal articleSahraoui F, Pin莽on JL, Belmont G, et al., 2003, , JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS, Vol: 108, ISSN: 2169-9380
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- Citations: 93
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Conference paperReisenfeld DB, Gosling JT, Steinberg JT, et al., 2003, , Pages: 210-213, ISSN: 0094-243X
From September through November 2001, Ulysses was almost continuously immersed in polar coronal hole (CH) flow during its northern polar pass of the Sun. For much of this time, the flow was fast (> 700 km/s) and steady, quite similar to the steady unstructured flow observed during Ulysses' first polar orbit near solar minimum. During the three months Ulysses transited the northern polar CH it observed 5 coronal mass ejections (CMEs). Of these, two were clearly over-expanding and two were at least partially driven by overexpansion. The phenomenon of over-expansion was frequently observed at high latitudes during Ulysses' first orbit. The recurrence of over-expanding CMEs during the second orbit at high latitudes indicates that this is a phenomenon apparently unique to and typical of CMEs embedded in polar CH flow. Ulysses was nearly above the solar limb during this three-month interval, providing an opportunity to use LASCO/SOHO observations to study the initial velocity profiles of the CMEs observed further out by Ulysses. These initial conditions were used as inputs into a hydrodynamic code, the results of which are reported here.
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Conference paperLin N, Kellogg PJ, MacDowall RJ, et al., 2003, , Pages: 534-537, ISSN: 0094-243X
We have compared observations of VLF waves (0.2 to 448 Hz) made by Ulysses during its second fast latitude scan (near the solar maximum) with the wave observations during the first fast latitude scan in 1995, when the solar activity was approaching a minimum. The occurrences and properties of the waves are found to be similar during the solar maximum and solar minimum periods for slow and intermediate speed solar wind. The maximum intensity of the electromagnetic waves for the two solar cycle periods is comparable. These similarities suggest that the plasma conditions for the waves' excitation are similar for the slow and intermediate solar wind in both solar maximum and minimum phases. It is also found that the electric field noise detected in the low band channels, which are measuring less than 9 Hz signals, is contaminated by the spin modulation of the electric field due to photoelectrons around the spacecraft, especially when the ambient plasma density is low. This noise increases with increasing solar aspect angle.
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Conference paperQureshi MNS, Pallocchia G, Bruno R, et al., 2003, , Pages: 489-492, ISSN: 0094-243X
One of the major issues in space plasma physics is that in spite of the inhomogeneity of interplanetary plasma and the complicated magnetic field topology we do not find strong deviations from Maxwellian distributions as it would be expected for a quasi-collisionless plasma. However, the presence of high energy tail and shoulders in the profile of distribution function stimulate to look for a better analytic representation of the observed distributions. Therefore, here we adopt a non-Maxwellian distribution function such as the Ellipsian distribution function, which is the generalized form of the Kappa distribution function. In this paper we have analysed the solar wind data recorded by Cluster s/c during early 2001 and 2002 when the s/c were repeatedly immersed in the solar wind, ahead of the Earth's bow shock. Data were modeled with the help of the Ellipsian distribution function and values of the best fit parameters were successively used to characterize the solar wind kinetics at different locations of one of the four Cluster s/c.
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Journal articleMessnarz D, Jaritz N, Arcimowicz B, et al., 2003, , PHYSICA SCRIPTA, Vol: 68, Pages: 170-191, ISSN: 0031-8949
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- Citations: 19
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