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Procedures are developed for accelerated laboratory tests of spacecraft polymers for resistance to long-term exposure to hyperthermal atomic oxygen (AO) with the use of high-energy AO ions of a rarefied plasma and Kapton-H polyimide as the reference material. The parameters that characterize physico-chemical, thermo-optical, and aerodynamic AO – Kapton-H interaction (surface roughness, solar absorptance, and normal infrared emittance) are determined at different values of the AO fluence. To do this, use was made of the data of tests onboard spacecraft in the Earth's atmosphere and the authors and others' laboratory tests. The normal and the tangential momentum transfer coefficient and the energy transfer coefficient are reported as a function of the AO bombardment angle. The obtained data on the AO-induced degradation of the parameters that characterize AO–polyimide dynamic interaction allow one to predict the behavior of the polyimide thermo-optical and aerodynamic properties during a long-term service in the Earth's upper atmosphere and ionosphere. • Physical modeling conditions for spacecraft – atomic oxygen interaction are given. • Atomic oxygen to polyimide momentum and energy transport coefficients are measured. • Atomic oxygen induced polyimide degradation parameters are determined. [ABSTRACT FROM AUTHOR]

Q-SAT, a small spherical satellite designed and developed by Tsinghua university, was successfully launched on Aug 6, 2020 at Jiuquan satellite launch center in China. The mission of Q-Sat is the joint measurement of long-wavelength Earth gravity field and upper atmosphere density, which is of great significance for improving spacecraft orbit prediction and promoting the development of satellite gravity measurement technology. The satellite is designed in spherical shape innovatively and deploys high dynamic dual-frequency GPS as the main payload. On-orbit data shows that the atmospheric density detection precision is in the order of 10−14kg/m3 and the gravity recovery precision achieves the level of 30 orders. All mission success criteria and objectives were achieved. This paper presents the design, space mission, key technologies, science capabilities and preliminary results of the satellite. • Q-SAT, a spherical satellite for the joint measurement of long-wavelength Earth gravity field and upper atmosphere density, was launched in 2020. • An electromagnetic separation system with point connection-release structure is designed for the Q-Sat. • As secondary payload a powerful GPU module is implemented to validate artificial intelligence computing capabilities in orbit. • Modifications for the Jacchia-Roberts atmospheric density model are proposed in the paper. [ABSTRACT FROM AUTHOR]

The results of the study of the gas-dust cloud of solid fuel combustion products dynamics formed under a rocket stages separation are presented. The sequence of the digital images obtained in the twilight condition at a distance of ∼1500 km from the missile trajectory was analyzed. The height of the cloud center reaches up to ∼900 km, and its diameter is ∼2000 km. The glow of the cloud is determined by the scattering of sunlight on dispersed particles of the combustion products. The obtained data allow to specify the dispersed composition of the cloud and dynamic parameters of its development. The proposed methodology can be used to clarify the physical picture of the interaction of the combustion products of solid propellant with the environment, as well as environmental conditions and processes in the upper atmosphere. • The height and diameter of the gas-dust cloud were measured. • The expansion velocity of the cloud is practically constant. • Calculated luminosity of the cloud is in satisfactory agreement with the measurement results. [ABSTRACT FROM AUTHOR]

"Flyby, orbit, land" has been the guiding philosophy of planetary exploration. This systematic approach has been highly successful in addressing the most fundamental questions of the origin, evolution, and habitability of the solar system. For the giant planets, entry probes take the place of "landers", since the "land" of the gas and icy giant planets, their solid core, lies some tens of thousands of kilometers beneath their cloud tops, hence impractical to reach. On the other hand, during a planet's accretionary heating phase the volatiles trapped in the core material would have been released, forming the atmosphere, together with the most volatile of the gases, hydrogen, helium and neon, that were captured gravitationally when the core became massive enough. Those atmospheric volatiles would thus be accessible by entry probes deployed to relatively shallow depths in the upper troposphere, allowing the determination of the abundances and isotopes of at least the most critical of the "heavy elements" (mass greater than helium). The heavy elements are key constraints to planetary formation and evolution models [1]. Entry probes are essential to retrieve their abundances, which are feasible only in situ at probe depths. That was the rationale behind NASA's 1995 Galileo probe mission at Jupiter and the Saturn Probe mission in NASA's New Frontier 4 candidate list of science themes. Saturn probe proposals to ESA's Cosmic Vision Program are similarly inspired. In 2015, NASA commissioned an Ice Giant Planets Study to recommend a comprehensive set of science goals and objectives, and further to develop potential mission architectures for accomplishing them in the 2023–2033 decade. The most highly rated mission from that study is an orbiter with probe to either Uranus or Neptune [2]. While remote sensing observations from the orbiter will yield the composition, structure and the distribution of neutral and charged particles in the magnetosphere and the upper atmosphere, the entry probe will determine the abundances and isotopic ratios of the noble gases (He, Ne, Ar, Kr, Xe), H, C, and possibly N and S. The noble gases, in particular, are key to discriminating among formation models, and their values from the probe entry location would represent global values as they are unaffected by meteorology, dynamics or chemistry. We will elaborate on these issues and then briefly discuss possible scenario/s for a mission to the icy giant planets, with particular focus on entry probes. • Heavy elements and isotopic ratios are key to giant planet formation models. • Noble gases provide the most robust constraints to models. • Only entry probes can make measurements of heavy elements and isotopes. • No new technology is required to enable an orbiter-probe mission to icy giants now. • Maturation of certain new technology would allow greater science return. [ABSTRACT FROM AUTHOR]

Experimental data on the extraordinary optical phenomena observed in our country and abroad during selected rocket launches are discussed. A particular interpretation of these data on the basis of common methodological and theoretical positions is presented. [ABSTRACT FROM AUTHOR]

This study proposes a method for the observation of the upper atmosphere using an artificial meteor injected by a mass driver installed on a microsatellite. The mass driver injects a pill at a velocity of 200 m/s and deorbits it into the atmosphere. The emission of the pill can then be observed from the ground at the necessary time and location. This approach could contribute to a better understanding of the global environment as well as different aspects of astronomy and planetary science. To realize the proposed method, the required size and emission of the pill have to be determined. Therefore, we conducted flow-field simulations, spectroscopic estimations, and an experiment on an artificial meteor in the arc heater wind tunnel at the Institute of Space and Astronautical Science in the Japan Aerospace Exploration Agency (ISAS/JAXA). From the results, we confirmed that the light emission could be observed as a shooting star by the naked eye and thus verified the feasibility of the method. [ABSTRACT FROM AUTHOR]

Since its launch on 20 May 2004, FORMOSAT-2 (FS2, Formosa satellite ♯2) has been operated on orbit for more than 9 years. It carries two payloads: the remote sensing instrument (RSI) for Earth observations and the imager of sprites and upper atmospheric lightning instrument (ISUAL) for the purpose of scientific observations. The RSI is operating at daytime while ISUAL is active at night-time. To meet both mission objectives simultaneously, the satellite operations planning has been more complicated. In order to maximize the usage of the on-board resources, the satellite attitude maneuver activities and power charge/discharge cycles have been scheduled cautiously in every detail. Under such fully engaged operations scenario and with a design life of 5 years, it is inevitable that the satellite encountered many anomalies, either permanent or temporary. In particular, one attitude gyro (totally four) and one reaction wheel (totally four) have been failed. This paper presents the major anomalies and resolutions in the past years. Many iterations and trade-offs have been made to minimize the effect on mission operations of the handicapped FORMOSAT-2. It still can provide about 80% of the designed functions and capabilities. [ABSTRACT FROM AUTHOR]

Abstract: This paper traces the development of rocket technology in Germany from the 1930s and 1940s that led to the massive, and historically unprecedented, transfer of rocket, missile, launch-vehicle and related technologies to the post-World-War-II United States. This achievement was made possible by an initial group of 118 German rocket specialists to which others were gradually added. The contributions to rocketry, upper atmosphere and space research, and eventually manned space travel provided by Germany''s Wernher von Braun and his team of engineers, scientists, technicians and support personnel is, in particular, described, and the ongoing influence of the innovations they introduced is considered. [Copyright &y& Elsevier]

Abstract: The magneto-plasma sail (mini-magnetospheric plasma propulsion) produces the propulsive force due to the interaction between the artificial magnetic field around the spacecraft inflated by the plasma and the solar wind erupted from the Sun with a speed of 300–800km/s. The principle of the magneto-plasma sail is based on the magnetic sail whose original concept requires a huge mechanical coil structure, which produces a large magnetic field to capture the energy of the solar wind. Meanwhile in the case of the magneto-plasma sail, the magnetic field will be expanded by the inertia of plasma flow to a few tens of kilometer in diameter, resulting in a thrust of a few Newton R. Winglee''s group of the University of Washington originally proposed the idea of magnetic field inflation by the plasma. This paper investigates the characteristics of the magneto-plasma sail by comparing it with the other low-thrust propulsion systems (i.e., electric propulsion and solar sail), and the potential of its application to near future outer planet missions is studied. Furthermore, an engineering validation satellite concept is proposed in order to confirm the propulsion system specification and operation methodology. The main features are summarized as: (1) The satellite mass is around 180kg assuming the H-IIA piggyback launch. (2) Since the magnetopause of the Earth magnetosphere is about 10Re at Sun side and the bow shock is located at about 13Re from the Earth, the satellite is injected into an orbit with 250km perigee altitude and 20Re apogee distance where apogee is located at the Sun side. (3) The magneto-plasma sail is turned on only in the vicinity of apogee outside the Earth''s magnetosphere. (4) The thrust is estimated by the orbit determination result, and the plasma wind monitor is installed on the satellite to establish the relationship between the solar wind and the thrust. [Copyright &y& Elsevier]

Abstract: Sounding rocket programs for upper atmospheric research (UAR) commenced at Woomera in 1957, with the British Skylark project and the Anglo–Australian HARP rockoon program. Shortly afterwards, the Weapons Research Establishment (WRE) inaugurated its own sounding rocket program with the first successful Australian-built sounding rocket, Long Tom, developed from surplus British motors. This research would eventually lead to the development of Australia''s first satellite, WRESAT, launched in 1967. Long Tom became the first more than 10 Australian designed and built sounding rockets that would be employed at Woomera until the demise of the WRE upper atmosphere program in 1976, as the Range was winding down to the cessation of the Anglo–Australian Joint Project. Like Long Tom, most of the early Australian sounding rockets were constructed by the WRE from surplus British motors, but after 1967 the later vehicles had a much higher local content, based on combinations of British motors and/or rocket motors developed in Australia. These new motors were named after constellations of the southern sky, while the rockets themselves bore the names of Australian native birds. This paper will outline the technical and scientific history of the Australian sounding rocket program, examining its origins and the reasons for its demise. It will look at the sequential development of the various Australian rockets and consider the particular research projects with which they were associated, the relationship with the WRESAT project and the move to Australian production after 1967. [Copyright &y& Elsevier]