Particle acceleration by magnetic reconnection and shocks during current loop coalescence in solar flares

This article reviews recent development of the theory of current loop coalescence and shock waves, giving particular attention to particle acceleration caused by these processes. First, explosive reconnection driven by the current loop coalescence and associated particle acceleration are studied by theoretical and magnetohydrodynamic simulation methods and the results are compared with observations of solar flares; this model gives a good explanation for the quasi-periodic structure of some solar flare bursts. Next follows a discussion of particle acceleration in association with fast magnetosonic shock waves. It is shown theoretically and by relativistic particle simulation that a quasi-perpendicular shock wave can accelerate trapped ions in the direction perpendicular to the ambient magnetic field up to speeds much greater than the Alfvén speed, . When the ambient magnetic field is rather strong ( _{ce pe} ), both ions and electrons can be accelerated to relativistic energies. For both the nonrelativistic and relativistic cases, the time needed for the acceleration is very short; it is for the ions. These results are compared with the rapid and simultaneous acceleration of ions and electrons in the impulsive phase of solar flares.     

A series of small scientific satellite with flexible standard bus

Japan Aerospace Exploration Agency has a plan to develop the small satellite standard bus for various scientific missions and disaster monitoring missions. The satellite bus is a class of 250–400 kg mass with three-axis control capability of 0.02 accuracy. The science missions include X-ray astronomy missions, planetary telescope missions, and magnetosphere atmosphere missions. In order to adapt the wide range of mission requirements, the satellite bus has to be provided with flexibility. The concepts of modularization, reusability, and product line are applied to the standard bus system. This paper describes the characteristics of the small satellite standard bus which will be firstly launched in 2011.     

Time variations of cosmic-ray helium isotopes with BESS-Polar I

The Balloon-borne Experiment with a Superconducting Spectrometer (BESS) is configured with a solenoidal superconducting magnet and a suite of precision particle detectors, including time-of-flight hodoscopes based on plastic scintillators, a silica-aerogel Cherenkov detector, and a high resolution tracking system with a central jet-type drift chamber. The charges of incident particles are determined from energy losses in the scintillators. Their magnetic rigidities (momentum/charge) are measured by reconstructing each particle trajectory in the magnetic field, and their velocities are obtained by using the time-of-flight system. Together, these measurements can accurately identify helium isotopes among the incoming cosmic-ray helium nuclei up to energies in the GeV per nucleon region. The BESS-Polar I instrument flew for 8.5 days over Antarctica from December 13th to December 21st, 2004. Its long-duration flight and large geometric acceptance allow the time variations of isotopic fluxes to be studied for the first time. The time variations of helium isotope fluxes are presented here for rigidities from 1.2 to 2.5 GV and results are compared to previously reported proton data and neutron monitor data.     

A study of land transformation processes after the atomic bombing damage in Hiroshima

We first analyzed aerial, satellite and surface photographs of Hiroshima taken in 1939, 1945, 1947, 1972, 1980 and 1982, in time sequence. It is rather difficult to recognize traces of damage caused by the atomic bombing from surface level with the few exceptions such as the Atomic Bomb Memorial Dome. However, the ground surface pattern of central Hiroshima analyzed by LANDSAT MSS data shows similarities to damage caused by the atomic bombing and the distribution of residual radioactivities.     

KIBO (Japanese Experiment Module in ISS) operations—2008/3–2009/10

Japan Aerospace Exploration Agency (JAXA) launched its own first manned experiment facility in space called the KIBO (Japanese Experiment Module, JEM) in 2008 and 2009 and started operations as part of International Space Station (ISS). To accomplish this Operation, JAXA made its own ground facility in Tsukuba, Japan, called Space Station Integration and Promotion Center (SSIPC). Ground personnel at SSIPC called the JEM Flight Control Team (JFCT) operate the KIBO and have learnt many lessons during its operation. In this presentation, some topics are chosen and explained such as (1) crew/ground personnel interaction and (2) planning lessons learned for manned space activities.