Type III bursts are generated by fast electron beams originated from magnetic reconnection sites of solar flares. As propagation of radio waves in the interplanetary medium is strongly affected by random electron density fluctuations, type III bursts provide us with a unique diagnostic tool for solar wind remote plasma measurements. Here, we performed a statistical survey of 152 simple and isolated type III bursts observed by the twin-spacecraft Solar TErrestrial RElations Observatory mission. We investigated their time-frequency profiles in order to retrieve decay times as a function of frequency. Next, we performed Monte Carlo simulations to study the role of scattering due to random electron density fluctuations on time-frequency profiles of radio emissions generated in the interplanetary medium. For simplification, we assumed the presence of isotropic electron density fluctuations described by a power law with the Kolmogorov spectral index. Decay times obtained from observations and simulations were compared. We found that the characteristic exponential decay profile of type III bursts can be explained by the scattering of the fundamental component between the source and the observer despite restrictive assumptions included in the Monte Carlo simulation algorithm. Our results suggest that relative electron density fluctuations /ne in the solar wind are 0.06-0.07 over wide range of heliospheric distances.
There is a critical need to predict the time course, magnitude, and individual variability in behavioral, cognitive, affective and interpersonal reactions of space explorers during long-duration missions. Accurate prediction will inform strategies for crew selection, spacecraft habitability requirements, and behavioral health countermeasures needed for interplanetary missions. High-fidelity simulated space flight has paramount importance in providing data on crew behavioral changes during prolonged confinement and isolation. However, the ecological validity of the simulation depends heavily upon the extent to which it instantiates elements relevant to crew behavior during prolonged confinement in space. These include crew characteristics and size, habitat and habitability, isolation from Earth's light-dark cycles and weather, mission duration and realistic mission operations, flight simulation with mission controllers, communication delays inherent in interplanetary missions, limited consumable resources, and attention from media and the public.
It is argued (a) that the onset times of type III radio emission and of the streaming electrons implies that type III bursts in the interplanetary medium are generated predominantly at the fundamental, (b) that in view of recent observations of ion-sound waves in the interplanetary medium the theory of the generation of the bursts should be revised to take account of these waves, and (c) the revised theory favours fundamental emission. A detailed discussion of the effect of ion-sound waves on type III bursts is given. The most important results are: (1) Ion-sound waves cause enhanced (over scattering off thermal ions) fundamental emission. (2) Second harmonic emission is also enhanced for Te> 5 105 K, e.g., low in the corona, but is suppressed for Te
Planetary protection is a guiding principle in the design of an interplanetary mission, aiming to prevent biological contamination of both the target celestial body and the Earth in the case of sample-return missions. Planetary protection reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.
There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if they exist, back to the Earth's biosphere.
The Committee on Space Research (COSPAR) meets every two years, in a gathering of 2000 to 3000 scientists, and one of its tasks is to develop recommendations for avoiding interplanetary contamination. Its legal basis is Article IX of the Outer Space Treaty  (see history below for details).
Analyses of 15,314 electron velocity distribution functions (VDFs) within 2 hr of 52 interplanetary (IP) shocks observed by the Wind spacecraft near 1 au are introduced. The electron VDFs are fit to the sum of three model functions for the cold dense core, hot tenuous halo, and field-aligned beam/strahl component. The best results were found by modeling the core as either a bi-kappa or a symmetric (or asymmetric) bi-self-similar VDF, while both the halo and beam/strahl components were best fit to bi-kappa VDF. This is the first statistical study to show that the core electron distribution is better fit to a self-similar VDF than a bi-Maxwellian under all conditions. The self-similar distribution deviation from a Maxwellian is a measure of inelasticity in particle scattering from waves and/or turbulence. The ranges of values defined by the lower and upper quartiles for the kappa exponents are κ ec 5.40-10.2 for the core, κ eh 3.58-5.34 for the halo, and κ eb 3.40-5.16 for the beam/strahl. The lower-to-upper quartile range of symmetric bi-self-similar core exponents is s ec 2.00-2.04, and those of asymmetric bi-self-similar core exponents are p ec 2.20-4.00 for the parallel exponent and q ec 2.00-2.46 for the perpendicular exponent. The nuanced details of the fit procedure and description of resulting data product are also presented. The statistics and detailed analysis of the results are presented in Paper II and Paper III of this three-part study.
Luna 3, an automatic interplanetary station, was the third spacecraft successfully launched to the Moon and the first to return images of the lunar far side. The spacecraft returned very indistinct pictures, but, through computer enhancement, a tentative atlas of the lunar farside was produced. These first views of the lunar far side showed mountainous terrain, very different from the near side, and only two dark regions which were named Mare Moscovrae (Sea of Moscow) and Mare Desiderii (Sea of Dreams). (Mare Desiderii was later found to be composed of a smaller mare, Mare Ingenii (Sea of Ingenuity) and other dark craters.)
Synopsis of Program:Solar, Heliospheric, and Interplanetary Environment (SHINE) is a broad-based research program supporting enhanced understanding of and predictive capabilities for the processes by which energy in the form of magnetic fields and particles are produced by the Sun and/or accelerated in interplanetary space and on the mechanisms by which these fields and particles are transported to the Earth through the inner heliosphere. Broad-based, grass-roots associations such as SHINE have developed to focus community effort on these scientific questions. Proposals are solicited for research directly related to topics under consideration and discussion at community workshops organized by SHINE under focused topic areas indicated in the program description. Information on the current activities of SHINE may be found at the following web site:
SHINE research focuses upon the connections between eruptive events and magnetic phenomena on the Sun and the corresponding solar wind structures in the inner heliosphere. SHINE fosters research on those processes by which magnetic fields and particles produced by the Sun permeate interplanetary space and on the mechanisms by which these fields and particles are transported to geospace through the inner heliosphere. The goal of SHINE research is to enhance both our physical understanding and predictive capabilities for solar driven geoeffective events. SHINE is therefore complementary to, but distinct from, the National Space Weather Program initiatives undertaken by the National Science Foundation and other agencies. The emphasis of SHINE is on basic research into solar and heliospheric processes, while the focus of the National Space Weather Program is on practical applications for forecasting and mitigating the adverse effects of space weather on technological systems on the Earth and in near-Earth space.
The Phase I model includes nodes and arcs in the Earth-Moon system and allows to run logistics scenarios up to and including buildup of a lunar outpost. The expanded model developed in Phase II will include additional nodes and edges in the Earth-Moon-Mars system and will allow simulating the interplanetary supply chain up to and including Mars missions.
This project brings to bear a unique combination of academic strengths in space systems and supply chain management at MIT with our partners at: Jet Propulsion Laboratory/California Institute of Technology
United Space Alliance
Payload Systems Inc. (now Aurura Flight Sciences)
to provide a theoretical and practical foundation for interplanetary supply-chain-management.
Any interplanetary supply-chain has to balance the requirements of reliability (redundant transportation modes) with cost-efficiency (few buffers, routes). We are helping NASA address this challenge directly. 041b061a72