Mass-, time-, and energy-characteristics of the interstellar flights during the long proper time of astronauts

The existence of extraterrestrial intelligence (ETI) and extraterrestrial scientific-technical civilization (STC) is of principal importance for CETI (communication with extraterrestrial intelligence) and SETI (search for extraterrestrial intelligence). According to Kardashev and Bracewell, the Earth-like STC in their farther development can expand to the nearby planetary systems of the Galaxy, creating galactic community (Bracewell's galactic club).In a previous paper the possibilities of the one-step relativistic rocket interstellar flight during the proper time of life of one-two generations of astronauts were analysed. The realization of such interstellar flights is very improbable, even to the nearest stars. These results could be true for the case of the comparatively short proper time of astronauts, i.e. large acceleration. But flights to the nearest stars could be realized with small and very small accelerations. In the present paper are calculated the proper times t in the reference systems connected with the astronauts (S₂), as well as the times T in the reference systems (S₁)-inertial, velocities v in S₁, mass ratios, powers and energies for various flights, exhaust velocities u and accelerations a. Results are critically discussed.     

极坐标系连续常值推力机动分析

连续常值推力是空间飞行常用的轨道机动方式，在空间交会与星际航行使命中具有重要的应用价值。其中，小推力适合于地球轨道航天器交会机动，而切向或周向推力以及较大的正径向推力可用于脱离地球引力场的逃逸飞行，执行星际交会使命。应用常推力作用下的极坐标系质心运动方程，对机动推力的量值没有限制；在航天器交会应用中，对相对距离也无要求。这种方法可直接获得向径与速度等轨道参数随时间或极角（绕地心的转动角）的变化，便于分析轨道转移与逃逸运动，有助于飞行使命与运动轨迹的设计。特别是，若机动转移的初轨为圆轨道，在推力较小、飞行时间不长的情况下，应用无量纲形式运动方程，可获得具有工程应用价值的近似解。文章给出一些有关的结果与应用案例。     

One method of controlling the motion of an aerospace vehicle during its long flight in the atmosphere

Based on the methods of the theory of optimum control of dynamic systems, as well as the methods of inverse problems of dynamics and the energy principle, a combined method is developed for control of the motion of a flying vehicle of the Aerospace plane type during the long flight in the atmosphere. The disturbed motion is considered under the conditions when there are constraints on the values of control actions and on functions of phase coordinates.     

Effect of geomagnetic field disturbances on the adaptive stress reaction of cosmonauts

Investigations of the effect of geomagnetic activity factors on the cardiac rhythm regulation and arterial pressure of cosmonauts during the expeditions onboard the Soyuz spacecraft, and the MIR and ISS orbital space stations was carried out for various durations of flight in weightlessness and, under control. Groups of cosmonauts were inspected under flight conditions outside the geomagnetic disturbances and in ground preflight conditions, during disturbances without them. The presence of specific effect of geomagnetic disturbances on the system of vegetative regulation of blood circulation of cosmonauts during the flight was demonstrated for the first time. The response of cosmonauts’ cardiac rhythm on the magnetic storm is definitely revealed; however, it depends on the initial functional background and, in particular, on the state of mechanisms of vegetative regulation (the duration of flight and adaptation to it).     

Space flight visual simulation.

In this paper, based on the scenes of stars seen by astronauts in their orbital flights, we have studied the mathematical model which must be constructed for CGI system to realize the space flight visual simulation. Considering such factors as the revolution and rotation of the Earth, exact date, time and site of orbital injection of the spacecraft, as well as its orbital flight and attitude motion, etc., we first defined all the instantaneous lines of sight and visual fields of astronauts in space. Then, through a series of coordinate transforms, the pictures of the scenes of stars changing with time-space were photographed one by one mathematically. In the procedure, we have designed a method of three-times "mathematical cutting." Finally, we obtained each instantaneous picture of the scenes of stars observed by astronauts through the window of the cockpit. Also, the dynamic conditions shaded by the Earth in the varying pictures of scenes of stars could be displayed.     

Investigation of CME properties using the data of SDO and PROBA2 spacecraft

Formation and motion (at the initial stage) of six limb CMEs detected in the period June 2010 to June 2011 are investigated using the high-resolution data of the PROBA2 and SDO spacecraft combined with the data of SOHO/LASCO coronagraphs. It is demonstrated that several loop-like structures of enhanced brightness originate in the region of CME formation, and they move one after another with, as a rule, different velocities. These loop-like structures in the final analysis form the frontal structure of CME. Time dependences of the velocity and acceleration of the ejection’s front are obtained for all CMEs under consideration. A conclusion is drawn about possible existence of two classes of CMEs depending on their velocity time profiles. Ejections, whose velocity after reaching its maximum sharply drops by a value of more than 100 km/s and then goes over into a regime of slow change, belong to the first class. Another class of CMEs is formed by ejections whose velocity changes slowly immediately after reaching the maximum. It is demonstrated that the CME’s angular dimension increases at the initial stage of ejection motion up to a factor of 3 with a time scale of doubling the angular size value within the limits 3.5–11 min since the moment of the first measurement of this parameter of an ejection. For three CMEs it is shown that at the initial stage of their motion for a certain time interval they are stronger expanded than grow in the longitude direction.     

火箭飞行异常遥测天线实时跟踪角度预测研究

针对火箭飞行异常下的遥测天线继续实时跟踪难的问题,提出一种飞行异常后的实时跟踪角度的预测方法。首先介绍几种常用坐标系以及坐标系之间的转换关系,并将火箭飞行异常后的运动简化为考虑惯性速度的自由落体运动,给出自由落体速度模型和实时跟踪角度的计算方法步骤。设计仿真实验,验证方法的有效性,可以作为火箭飞行异常后遥测天线实时跟踪角度预测的有效参考。     

Reconstruction of spacecraft rotational motion using a Kalman filter

Quasi-static microaccelerations of four satellites of the Foton series (nos. 11, 12, M-2, M-3) were monitored as follows. First, according to measurements of onboard sensors obtained in a certain time interval, spacecraft rotational motion was reconstructed in this interval. Then, along the found motion, microacceleration at a given onboard point was calculated according to the known formula as a function of time. The motion was reconstructed by the least squares method using the solutions to the equations of satellite rotational motion. The time intervals in which these equations make reconstruction possible were from one to five orbital revolutions. This length is increased with the modulus of the satellite angular velocity. To get an idea on microaccelerations and satellite motion during an entire flight, the motion was reconstructed in several tens of such intervals. This paper proposes a method for motion reconstruction suitable for an interval of arbitrary length. The method is based on the Kalman filter. We preliminary describe a new version of the method for reconstructing uncontrolled satellite rotational motion from magnetic measurements using the least squares method, which is essentially used to construct the Kalman filter. The results of comparison of both methods are presented using the data obtained on a flight of the Foton M-3.     

Orbital manoeuvres of free flying platforms for retrieval by space shuttle

In a typical future mission a free flying platform will be released to space by Space Shuttle. After performing its active mission, it will have to wait for a suitable later Shuttle flight for retrieval at its original orbital altitude. To allow for the orbital descent during the total mission time of typically several months, one or several orbit raise manoeuvres have to be performed with the platform's own propulsion system. In the paper, the velocity-requirements Δv for these orbital transfers, depending on Sun activity, rendezvous-altitude, ballistic coefficient and longest expected mission time are treated.The simplest manoeuvre, consisting of one initial ascent transfer and one descent transfer at the actual retrieval date, is shown to be not optimal. Up to 25% of Δv can be saved, if several orbit raising transfers in a certain sequence are applied. A straightforward analytical treatment is presented for the optimization, while a computer program with the CIRA-atmosphere model is used for actual mission planning.     

T cell regulation in microgravity – The current knowledge from in vitro experiments conducted in space,parabolic flights and ground-based facilities

Dating back to the Apollo and Skylab missions, it has been reported that astronauts suffered from bacterial and viral infections during space flight or after returning to Earth. Blood analyses revealed strongly reduced capability of human lymphocytes to become active upon mitogenic stimulation. Since then, a large number of in vitro studies on human immune cells have been conducted in space, in parabolic flights, and in ground-based facilities. It became obvious that microgravity affects cell morphology and important cellular functions. Observed changes include cell proliferation, the cytoskeleton, signal transduction and gene expression. This review gives an overview of the current knowledge of T cell regulation under altered gravity conditions obtained by in vitro studies with special emphasis on the cell culture conditions used. We propose that future in vitro experiments should follow rigorous standardized cell culture conditions, which allows better comparison of the results obtained in different flight- and ground-based experiment platforms.     

Spacelab experiments on space motion sickness

Recent research results from ground and flight experiments on motion sickness and space sickness conducted by the Man Vehicle Laboratory are reviewed. New tools developed include a mathematical model for motion sickness, a method for quantitative measurements of skin pallor and blush in ambulatory subjects, and a magnitude estimation technique for ratio scaling of nausea or discomfort. These have been used to experimentally study the time course of skin pallor and subjective symptoms in laboratory motion sickness. In prolonged sickness, subjects become hypersensitive to nauseogenic stimuli. Results of a Spacelab-1 flight experiment are described in which four observers documented the stimulus factors for and the symptoms/signs of space sickness. The clinical character of space sickness differs somewhat from acute laboratory motion sickness. However SL-1 findings support the view that space sickness is fundamentally a motion sickness. Symptoms were subjectively alleviated by head movement restriction, maintenance of a familiar orientation with respect to the visual environment, and wedging between or strapping onto surfaces which provided broad contact cues confirming the absence of body motion.     

Rotational motion of <Emphasis Type="Italic">Foton M-4</Emphasis>

The actual controlled rotational motion of the Foton M-4 satellite is reconstructed for the mode of single-axis solar orientation. The reconstruction was carried out using data of onboard measurements of vectors of angular velocity and the strength of the Earth’s magnetic field. The reconstruction method is based on the reconstruction of the kinematic equations of the rotational motion of a solid body. According to the method, measurement data of both types collected at a certain time interval are processed together. Measurements of the angular velocity are interpolated by piecewise-linear functions, which are substituted in kinematic differential equations for a quaternion that defines the transition from the satellite instrument coordinate system to the inertial coordinate system. The obtained equations represent the kinematic model of the satellite rotational motion. A solution of these equations that approximates the actual motion is derived from the condition of the best (in the sense of the least squares method) match between the measurement data of the strength vector of the Earth’s magnetic field and its calculated values. The described method makes it possible to reconstruct the actual rotational satellite motion using one solution of kinematic equations over time intervals longer than 10 h. The found reconstructions have been used to calculate the residual microaccelerations.     

Determination of parameters of rotational motion of the <Emphasis Type="Italic">Monitor-E</Emphasis> spacecraft from the telemetry data on solar batteries’ current

The Monitor-E spacecraft executed uncontrolled flight due to emergency situation, no telemetry information on parameters of the spacecraft’s attitude motion being available. So, the problem arose to determine the spacecraft’s rotational motion from the accessible indirect information—the electric current provided by solar batteries. In this paper the integrated statistical technique is described, that allows one to solve this problem. The values of current, obtained over the time interval some tens of minutes long, have been processed simultaneously by the least squares method using the integration of the equations of spacecraft’s rotational motion. As a result of processing, the initial conditions of motion were estimated, and the spacecraft’s moments of inertia were updated, as well as the angles, specifying solar batteries position in the spacecraft-fixed coordinate system. The results of processing of 12 data sets are presented, which allowed us to reconstruct the actual rotational motion of the spacecraft.     

Visions of exploration

The word “exploration” threads its way through every discussion of human space flight and often headlines national policy statements about the US space agency. Yet this concept, so rooted in our culture, remains remarkably ill-defined. In this paper, we examine various presumptions implicit in the term and its ramifications for federally supported space endeavors. We argue that historical examples of exploration, widely used by policy makers, often make poor models for contemporary space travel. In particular, historical precedents of exploration set up a land-biased view of discovery, a restriction which impedes full expression of the Vision for Space Exploration and its possible scientific returns. These same precedents also set up a view of discovery that is biased toward in situ human presence, a view that modern technology is rendering increasingly absurd.     

Low-Frequency Microaccelerations onboard the Foton-11 Satellite

We analyze the microacceleration measurements carried out onboard the Foton-11 satellite with the three-component accelerometer BETA. The microaccelerations were recorded virtually throughout the entire orbital flight of the Foton-11 satellite. The data obtained were analyzed in the following way. First they were used to determine the actual rotational motion of the satellite for several arbitrarily selected time intervals 4 h long. This problem was solved by constructing the approximation of the microacceleretation low-frequency component (previously determined from the data) by its calculated analog computed along the solutions to differential equations of rotational motion of the satellite. The approximation was made by the least squares method. As a result, those mathematical model parameters and the solutions to equations of motion were found that gave the best consistency of the microacceleretation low-frequency component and its calculated analog. Then the spectral analysis of the low-frequency component and its calculated analog was made. It was shown that, although basic harmonics of these functions coincided sufficiently well, some harmonics of the low-frequency component failed to be interpreted in terms of the satellite's rotational motion.     

Haploid deletion strains of Saccharomyces cerevisiae that determine survival during space flight

This study identifies genes that determine survival during a space flight, using the model eukaryotic organism, Saccharomyces cerevisiae. Select strains of a haploid yeast deletion series grew during storage in distilled water in space, but not in ground based static or clinorotation controls. The survival advantages in space in distilled water include a 133-fold advantage for the deletion of PEX19, a chaperone and import receptor for newly- synthesized class I peroxisomal membrane proteins, to 77–40 fold for deletion strains lacking elements of aerobic respiration, isocitrate metabolism, and mitochondrial electron transport. Following automated addition of rich growth media, the space flight was associated with a marked survival advantage of strains with deletions in catalytically active genes including hydrolases, oxidoreductases and transferases. When compared to static controls, space flight was associated with a marked survival disadvantage of deletion strains lacking transporter, antioxidant and catalytic activity. This study identifies yeast deletion strains with a survival advantage during storage in distilled water and space flight, and amplifies our understanding of the genes critical for survival in space.     

同时地形高程测量和地面运动目标检测的分布式InSAR最优编队构形

分布式小卫星干涉SAR为了同时获得时间基线(用于地面运动目标检测)和空间基线(用于地形高程测量),采取空间立体编队构形(即非沿航向直线编队),然而这种混合基线的情况会导致地面运动目标与地形杂波存在相位耦合,而且只靠信号处理方法很难分离,这对于检测地面运动目标极为不利。提出几种最优编队构形,在保证获得两种干涉基线的同时,通过对消两对干涉SAR图像来抑制掉固定杂波,从而可以检测地面运动目标,这种方法具有处理简单和性能较好等优点。最后给出了仿真结果。     

基于陀螺力学的旋转导弹锥形运动分析

针对旋转导弹飞行中弹体的锥形运动,利用陀螺动力学中的双自由度陀螺线性扰动方程建立数学模型,分别分析了纵向静稳定力矩和侧向力矩对旋转导弹锥形运动的作用机理;利用布尔加可夫相空间方程组,分析线性气动阻尼对旋转导弹的锥形运动的影响。结果表明, 旋转导弹锥形运动的幅度随弹体气动静稳定性而增加,故气动参数m αz的选择应以导弹质心最靠后时仍能保持弹体纵向中立静稳定为标准, 而且线性气动阻尼对旋转导弹的锥形运动的稳定是不利的,并最后导致旋转导弹锥形运动的发散。     

Vestibular tests in the selection of cosmonauts.

Vestibulo-vegetative disorders in cosmonauts and astronauts occurring during space flight compel otolaryngologists to search for vestibular tests enabling a precise evaluation of the activity of the vestibular apparatus and showing disposition to motion sickness. Otoneurological investigation of Polish candidates for cosmonaut status consisted of the following vestibular tests: caloric, rotatory, optokinetic, swinging torsion, statokinesimetric and vestibulo-vegetative. The value of various vestibular tests for aviation and space medicine is presented in this paper, taking into account the results of investigations of the equilibrium system with the group of pilots selected for space flight as well as extensive experience with candidates for the air service and also trained pilots and patients. The relatively frequent lack of correlation between the results of the applied tests, which renders difficult the proper evaluation of the equilibrium system, is emphasized in the paper. Finally, the results of investigations of acute habituation of the vestibular apparatus are discussed.