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Detection of ultrahighenergy cosmic rays and neutrinos by radio method using artificial lunar satellites


An estimate of the feasibility of the ultrahighenergy cosmic ray and neutrino detection using a lunar satelliteborne radio receiver is presented.


At the same time the lunar radio detector provides a means of searching for ultrahighenergy neutrinos with a high sensitivity combined with a very large target effective mass.


Optimizing Instrumental Neutron Activation Analysis of Extraterrestrial Materials: Fragments of Lunar Rocks, Meteorites, Chondru


It was shown that, along with geothermal brines (oceanic water), the most promising natural materials to be tested for SHEs are some volcanic (fumarole, griffon) products, lunar rocks, and asteroids.

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 This paper discusses the problem of distribution of points on the moon's surface intersected by the orbits of several kinds of lunar rocket, based on the planar and space double twobody problem. First we obtained the ingressregion on the moon's sphere of influence in which the orbits with different initial veloceties can hit the moon vertically, slantingly and tangentially. Then we get the distribution of hitting points on moon's surfaceof these orbits; hence we determine the forbbiden regions on the... This paper discusses the problem of distribution of points on the moon's surface intersected by the orbits of several kinds of lunar rocket, based on the planar and space double twobody problem. First we obtained the ingressregion on the moon's sphere of influence in which the orbits with different initial veloceties can hit the moon vertically, slantingly and tangentially. Then we get the distribution of hitting points on moon's surfaceof these orbits; hence we determine the forbbiden regions on the moon's surface of hitting orbits with different initial velocities. The result of calculation shows that: the magnitude of forbbiden region mainly depends upon the magnitude of initial velocity, when the initial velocity increases, then the magnitude of forbbided region increases monotonically; in the case of ascending orbits, the position of forbbiden region is at the posterior part (opposite to the direction of lunar motion) of the invisible half of the moon's surface; in the case of descending orbits, the position of forbbiden region is at the posterior part of the visible half of the moon's surface. Consequently, the anterior part of the invisible half of the moon can be hitten by ascending orbit; and every point on the moon's surface can be hitten by an ascending or descending orbit with specified initial velocity.  本文以平面和空間的双二体問題为基础,研究了几种类型的击中月球火箭的軌道在击中月球时同月面交点的分布問題。得到了几种不同初始速度能垂直击中,傾斜击中以及切向击中月球的軌道在月球作用范圍边界上的进口范圍。然后得出这些軌道在月面上击中点的分布情况;从而得出不同初始速度的軌道在月面上击中的禁区。从計算結果可看出:禁区大小主要同初始发射速度有关,速度愈大則禁区也愈大;禁区位置对上升軌道而言,在月球背面的后部(同月球运动反方向的部份),对下降軌道而言,在月球正面的后部;因此,用上升軌道也可以击中月球背面的一部份(前部),用适当的初始速度和軌道类型(上升或下降),可以击中月面上任何一点。  The purpose of this investigation is to study the possibility and condition for a lunar probe to hit or to fly over, at close range, any given region on the surface of the moon. We limit the ballistic speed of the vehicle to 11.2 km/sec and require that the height at the last burn out point should be about a few hundred kilometres. Six definite regions on the surface of the moon are considered as the objectives of these flights. Four regions lie on the great circle where the orbital plane of the moon cuts... The purpose of this investigation is to study the possibility and condition for a lunar probe to hit or to fly over, at close range, any given region on the surface of the moon. We limit the ballistic speed of the vehicle to 11.2 km/sec and require that the height at the last burn out point should be about a few hundred kilometres. Six definite regions on the surface of the moon are considered as the objectives of these flights. Four regions lie on the great circle where the orbital plane of the moon cuts the lunar surface. They are designated as the "near", "remote", "east", and "west" points. For these points, only trajectories in the orbital plane of the moon have been considered. The other two regions, namely, the poles of the aforesaid great circle, are called the "north" and "south" points respectively. In the preliminary survey of the possible trajectories, the approximate method of assuming the earthmoon space as divided into two by a sphere of action of radius 66000 km around the moon has been employed. The trajectory may then be considered to consist of several sections, each one of which is determined by the laws of twobody problem. From considerations on the permissible angular momentum of the orbit, it has been possible to derive limiting values for the velocity of hitting and the angle of incidence in the case of impact trajectories. For reconnaissance trajectories, we try to find out the allowable perilunar distance and velocity as well as how close may the perilunar point of the trajectory be brought to the surface of the moon. From preliminary investigation by the approximate method of sphere of action, we have come to the following conclusions: A. For impact trajectories: 1) To hit either the near or the remote point, the vehicle must be approaching the moon from the east side. With velocity of impact somewhere in the range 160—180km/min, the probe may hit these points at an angle of incidence of 30° or greater. 2) Vertical impact is possible only at the east point with the velocity of hitting at slightly less than 160 km/min. 3) The west point may be hit by a lunar probe, but only at grazing incidence. 4) The trajectories for hitting the north and the south points could be mirror images of each other. These points may be hit at an angle of incidence of about 60°, at a speed of less than 160 km/min. B. For reconnaissance trajectories: 1) Over the near and the remote points, there is a whole series of symmetrical orbits in which the vehicle would be sure to return to the neighbourhood of the earth. When the perilunar velocity is about 100 km/min, the distance of close approach to the centre of the moon may be no more than 5000 km. We can make the trajectory come in contact with the surface of the moon, if we allow the perilunar velocity to be increased to 160 km/min. 2) With perilunar distance over 30000 km, it is possible for the vehicle to fly horizontally over the east point of the moon. Such reconnaissance flight is possible over the west point, but the vehicle has to be so low that the orbit becomes identical with the impact trajectory grazing the west point. 3) When the perilunar point of the orbit may be permitted to deviate about 45° from the zenith of the east or the west point, we can still have reconnaissance trajectories that will bring the vehicle back to the neighbourhood of the earth. 4) When we consider only trajectories whose motion inside the sphere of action is in a plane perpendicular to the earthmoon direction, we could have symmetrical orbits with horizontal flight over the north or the south point at a distance of about 24000 km from the centre of the moon. With permissible values at the moon for different definite points, the path of the vehicle is traced backward in time to verify if it did pass by the vicinity of the earth with reasonable speed. If so, the position and velocity of the vehicle near the earth are taken as the initial values at the last burn out point, and the impact or reconnaissance trajectory is computed once again. In such computations the attractions of both the moon and the earth are taken into account by the method of numerical integration. The trajectories thus obtained are listed in Tables 5, 6, and 7.  在月球表面上考虑了六个定点,它们是自道面内的近、远、东、西四点和此外的南北两点。为了要找到可以实现用火箭击中和航测这六点的轨道,我们以在月面定点上可以容许的初值为轨道出发点,倒推出火箭在地球附近时的位置和速度。月面定点上的初值是依据火箭大约在地面上200公里高空以第二宇宙速度发射的假定选取的。所用方法是按作用范围和简单的角动量和能量守恒的原理来考虑的。计算结果表明,火箭从地面上以通常的高度和速度发射能够击中这六个定点:东点可以垂直击中,西点只能切向击中。航测这六个定点,都可以找到有去有回的轨道,航测远、近、南、北四点还可以有对称的轨道。航测远、近点可以和月面接近到任意距离,航测其他各点,距离便要远些,约为二、三万公里。  The data of this paper were obtained with the 16in refractor (D= 40 cm, F = 690 cm) from observations made immediately after the total lunar eclipse of Sep. 15, 1913. The values of measurements of radiusvectors have been published in Annals of ZoSè Observatory Vol.Ⅹ 1915. We corrected for differential refration and the defect, of which all the maximum values were only 0."13. It has been found from these data that the most probable figure of the moon's disk is an ellipse with flattening 1/1150; this... The data of this paper were obtained with the 16in refractor (D= 40 cm, F = 690 cm) from observations made immediately after the total lunar eclipse of Sep. 15, 1913. The values of measurements of radiusvectors have been published in Annals of ZoSè Observatory Vol.Ⅹ 1915. We corrected for differential refration and the defect, of which all the maximum values were only 0."13. It has been found from these data that the most probable figure of the moon's disk is an ellipse with flattening 1/1150; this corresponds to a difference between the major and minor axes amounting to 1."5. The major axis is inclined to the axis of rotation of the moon at an angle of 2° (from N. W. to S. E.), libration 1 =1.°1, b =0.°4. In order to obtain the parameters of the ellipse, it is recommended to use the method of the Fourier series.  月球轮廓是指投影在天球上的月球边缘平均形状。本文资料取自佘山天文年刊第十卷(1915年),这些月球照片系在1913年9月赤道仪(D=40cm,F=6.90m)所拍。本文求得月球轮廓的最或然形状是椭圆,长轴此短轴长1″.5,印扁率约为1/1150;长轴方向与自转轴的交角为2°(偏西)。看来,利用谐波分析方法来求椭圆参数,更为简单而不失其精确度。   << 更多相关文摘 
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