Space Physics
We propose the concept of a space mission to probe the so called flyby anomaly, an unexpected velocity change experienced by some deep-space probes using earth gravity assists. The key feature of this proposal is the use of GNSS systems to…
We report on a new Monte Carlo method for simulating diffusive shock acceleration (DSA) of solar energetic particles at upstream and downstream regions of quasi-parallel collisionless shock waves under the influence of self-generated…
In this paper we investigate the impact of permanent oscillations Pc3 on the excitation of sporadic oscillations Pi2 ( their periods are 10-45 and 40-150 s, respectively ). The hypothesis is formulated that Pc3 oscillations originating in…
We present the search for eclipsing binaries with a pulsating component in the first catalogue of optically variable sources observed by OMC/INTEGRAL, which contains photometric data for more than 1000 eclipsing binaries. Five objects were…
We hypothesize a simple scenario to associate spiral-shaped trajectories and asymptotic tangential velocities according to observations found on deep space scales. As a difference with alternative Modified Newton Dynamics (MoND), in our…
The concept of diffusion in collisionless space plasmas like those near the magnetopause and in the geomagnetic tail is reexamined from a fundamental statistical point of view making use of the division of particle orbits into waiting…
The intermittency of density fluctuations in the solar wind at kinetic scales has been examined using high time resolution Faraday cup measurements from the Spektr-R spacecraft. It was found that the probability density functions (PDFs) of…
The acceleration of protons and electrons to high (sometimes GeV/nucleon) energies by solar phenomena is a key component of space weather. These solar energetic particle (SEP) events can damage spacecraft and communications, as well as…
In this paper, we study the effects of the acceleration gravity on the sedimentation deposition probability, as well as the aerosol deposition rate on the surface of the Earth and Mars, but also aboard a spacecraft in orbit around Earth and…
Metals are the most common materials used in space technology. Metal structures, while used in space, are subjected to the full spectrum of the electromagnetic radiation together with particle irradiation. Hence, they undergo degradation.…
Space weather refers to dynamic conditions on the Sun and in the space environment of the Earth, which are often driven by solar eruptions and their subsequent interplanetary disturbances. It has been unclear how an extreme space weather…
The aim of this paper is the modeling and simulation of impact of space radiation variability on total dose and single event effects in spaceborne electronics. It has been shown that the simultaneous thermal annealing may lead to…
Location of formation of periodic solar wind number density structures is discussed. Observation of proton and alpha anticorrelation in these structures [Viall et al., 2009] indicates that taking into account that bulk velocity of…
This paper presents a study of Pc4-5 geomagnetic pulsations illustrated by those which were observed after the sudden commencement of May 02 of 2010 at 09 : 08 UT at the Brazilian stations TTB, VSS and SMS. We carry out the spectral…
The solar quiet daily variation (Sq) was investigated with respect to the longitudinal and seasonal variations at the Brazilian geomagnetic ground stations of Tatuoca (TTB), Vassouras (VSS ) and S\~ao Martinho da Serra (SMS). The data…
Temporal variation of secondary cosmic rays (SCR) flux was measured during the total lunar eclipse on December 10, 2011 and the subsequent full moon on January 8, 2012. The measurements were done at Department of Physics, University of…
The geomagnetic Kp index is derived from the K index measurements obtained from thirteen stations located around the Earth geomagnetic latitudes between $48^\circ$ and $63^\circ$. This index is processed every three hours, is…
We have studied a set of 41 magnetic clouds (MCs) measured by the ACE spacecraft, using the discrete orthogonal wavelet transform (Daubechies wavelet of order two) in three regions: Pre-MC (plasma sheath), MC and Post-MC. We have used data…
The neutrals in the Earth environment are in fact free and subjected to drag forces (by ions). In this study we show that drag or friction forces in the ionosphere-thermosphere system initiate changes in the plasma flow, neutral wind, and…
The paper describes differences in the intensity as a function of radial distance of anomalous and galactic cosmic rays in the N-S heliosheaths as observed by the Voyager 1 and 2 spacecraft respectively. The anomalous cosmic ray (ACR)…