Evolution of Periodic Orbits in the Sun-Saturn System

We analyze the periodic orbits, quasi periodic orbits and chaotic orbits in the photo gravitational Sun-Saturn system incorporating actual oblateness of Saturn in the planar circular restricted three body problem. In this paper, we study the effect of solar radiation pressure on the location of Sun centered and Saturn centered orbits, its diameter, semi major axis and eccentricity by taking different values of solar radiation pressure q and different values of Jacobi constant “C”, and by considering actual oblateness of Saturn using Poincare surface of section (PSS) method. It is ob-served that by the introduction of perturbing force due to solar radiation pressure admissible range of Jacobi constant C decreases, it is also observed that as value of C decreases the number of islands decreases and as a result the number of periodic and quasi periodic orbits decreases.Fur-ther, the periodic orbits around Saturn and Sun moves towards Sun by decreasing perturbation due to solar radiation pressure q for a specific choice of Jacobi constant C. It is also observed that due to solar radiation pressure, semi major axis and eccentricity of Sun centered periodic orbit reduces, whereas, due to solar radiation pressure uniform change in semi major axis and eccen-tricity of Saturn centered periodic orbits is observed.

Evolution of the “f” Family Orbits in the Photo Gravitational Sun-Saturn System with Oblateness

We analyze the periodic orbits of “f” family (simply symmetric retrograde periodic orbits) and the regions of quasi-periodic motion around Saturn in the photo gravitational Sun-Saturn system in the framework of planar circular restricted three-body problem with oblateness. The location, nature and size of these orbits are studied using the numerical technique of Poincare surface of sections (PSS). In this paper we analyze these orbits for different solar radiation pressure (q) and actual oblateness coefficient of Sun Saturn system. It is observed that as Jacobi constant (C) increases, the number of islands in the PSS and consequently the number of periodic and quasi-periodic orbits increase. The periodic orbits around Saturn move towards the Sun with decrease in solar radiation pressure for given value of “C”. It is observed that as the perturbation due to solar radiation pressure decreases, the two separatrices come closer to each other and also come closer to Saturn. It is found that the eccentricity and semi major axis of periodic orbits at both separatrices are increased by perturbation due to solar radiation pressure.

Multiverse/Hyperverse Models: (4 + 1)-Dimensional Landscape (Black Saturns, Bousso-Hawking Nucleation, Gogberashvili Multiverses, Schwarzschild-De Sitter Nurseries) and a (3 + 1)-Dimensional Model for Dark Energy

We consider the Hyperverse as a collection of multiverses in a (4 + 1)-dimensional spacetime with gravitational constant G. Multiverses in our model are bouquets of thin shells (with synchronized intrinsic times). If gis the gravitational constant of a shell Sand εits thickness, then G~εg. The physical universe is supposed to be one of those thin shells inside the local bouquet called Local Multiverse. Other remarkable objects of the Hyperverse are supposed to be black holes, black lenses, black rings and (generalized) Black Saturns. In addition, Schwarzschild-de Sitter multiversal nurseries can be hidden inside those Black Saturns, leading to their Bousso-Hawking nucleation. It also suggests that black holes in our physical universe might harbor embedded (2 + 1)-dimensional multiverses. This is compatible with outstanding ideas and results of Bekenstein, Hawking-Vaz and Corda about “black holes as atoms” and the condensation of matter on “apparent horizons”. It allows us to formulate conjecture 12.1 about the origin of the Local Multiverse. As an alternative model, we examine spacetime warping of our universe by external universes. It gives data for the accelerated expansion and the cosmological constant Λ, which are in agreement with observation, thus opening a possibility for verification of the multiverse model.

Quantum Locking and the Meissner Effect Lead to the Origin and Stability of the Saturn Rings System

It is demonstrated how superconducting iced particles of the protoplanetary cloud of Saturn are coming to magnetic equator plane and create the stable enough rings disk. There are two steps. First, after appearance of the Saturn magnetic field due to Meissner phenomenon, all particles orbits are moving to the magnetic equator plane. Finally they become distributed as rings and gaps like iron particles around magnet on laboratory table. And they are separated from each other by the magnetic field expelled from them. It takes up to few tens of thousands years with ten meters rings disk thickness. Second, because of quantum locking all particles become to be locked within magnetic well at the magnetic equator plane due to Abrikosov vortex for superconductor. Finally each particle is locked within three-dimensional magnetic well. It works even when particles have small fraction of superconductor. During the rings evolution some contribution to the disk also could come from the collision-generated debris of the current moon, coming meteorites and from the geysers like it happened due to magnetic coupling of Saturn and Enceladus. The rings are relict of the early days of the magnetic field of Saturn system.

Astrometric Reduction of Saturnian Satellites with Cassini-ISS Images Degraded by Trailed Stars

The Imaging Science Subsystem(ISS)mounted on the Cassini spacecraft has taken a lot of images,which provides an important source of high-precision astrometry of some planets and satellites.However,some of these images are degraded by trailed stars.Previously,these degraded images cannot be used for astrometry.In this paper,a new method is proposed to detect and compute the centers of these trailed stars automatically.The method is then performed on the astrometry of ISS images with trailed stars.Finally,we provided 658 astrometric positions between 2004 and 2017 of several satellites that include Enceladus,Dione,Tethys,Mimas and Rhea.Compared with the JPL ephemeris SAT427,the mean residuals of these measurements are 0.11 km and 0.26 km in R.A.and decl.,respectively.Their standard deviations are 1.08 km and 1.37 km,respectively.The results show that the proposed method performs astrometric measurements of Cassini ISS images with trailed stars effectively.

土星系探测任务进展与展望

《2021中国的航天》白皮书表示中国行星探测工程将实施小行星探测、火星采样返回、木星系探测等任务,对于更为远期的行星探测任务尚未有明确规划。土星是太阳系第二大行星,拥有美丽的星环和众多天然卫星,其中土卫二可能存在冰下海洋、土卫六是太阳系第二大天然卫星且是唯一一个拥有浓密大气的卫星,均具有极大的科学研究价值。本文对国外土星探测任务的发展状况进行了调研分析,包括已实施的先驱者11号、旅行者1号、旅行者2号、卡西尼-惠更斯号,以及后续的土卫二轨道-着陆器、土卫二多次飞越探测等。对这些任务的特点及实施土星系探测面临的关键难点进行了归纳总结。最后,提出了土星系探测的总体任务设想,进行了任务分析与初步设计,可作为中国后续行星探测任务规划的参考。

SATURN软启动器在连铸机大包回转台电机控制中的应用

介绍SATURN软启动器的结构和功能,阐述了软启动器在大包回转台控制中的应用和控制效果。

Preliminarily study of Saturn’s upper atmosphere density by observing Cassini plunging via China’s deep space station

When the Cassini spacecraft finally plunged into the Saturnian atmosphere on 2017 September15,China’s deep space telescope pointed to Saturn to observe Cassini and study the Saturnian upper neutral atmosphere.In this first Chinese Saturnian radio science experiment,X band Doppler velocity radio science data between the deep space telescope and the Cassini spacecraft were obtained.After removing Saturnian and solar gravity effects,Earth rotation effect,the remaining Saturnian atmosphere drag information was retrieved in the Cassini final plunge progress.Saturn’s upper neutral atmosphere mass density profile is approximately estimated based on atmosphere mass density derived principally by real orbit measurement data.Saturn’s upper neutral atmosphere mass density from 76000 km to 1400 km is estimated from the orbit measurement data,the mass density results are about from 1.4×10^-15 kg cm^-3 to 2.5×10^-14 kg cm^-3.

地层流体取样和压力测量Saturn 3D圆径探头

地层流体取样和压力测量Saturn 3D圆径探头由Schlumberger公司研发,该探头设有4个自密封吸入口,每个吸入口的过流面积为128.1cm2,与常规探头相比,过流面积增大了500倍以上。4个吸入口间隔90°安装在探头上,从地层吸取流体。吸入口装有过滤装置,当其靠在井壁上吸取地层流体时,可有效避免堵塞,使流体持续流动。该探头可实时监测滤液的清除情况,提取未污染的地层流体。该探头集成了地层动态测试器（MDT）,一次起下作业即可完成大范围的产能测试、渗透试验及地层流体取样，从而建立储层预测模型，确定流体的组分和储层的连通性。

A prediction method for ground-based stellar occultations by ellipsoidal solar system bodies and its application

A new programmable prediction method is developed to refine the occultation band by taking into consideration the triaxiality of an occulting body, as well as two more factors, namely, the barycenter offset of an occulting planet from the relevant planetary satellite system and the gravitational deflection of light rays due to an occulting planet. Although these factors can be neglected in most cases, it is shown that there are cases when these factors can cause a variation ranging from several tens to thousands of kilometers in the boundaries of occultation bands. Knowledge of analytic geometry simplifies the process of derivation and computation. This method is applied to long-term predictions of Jovian and Saturnian events.

Observations of loading-unloading process at Saturn's distant magnetotail

Using in-situ measurements from the Cassini spacecraft in 2013, we report an Earth substorm-like loading-unloading process at Saturn's distant magnetotail. We found that the loading process is featured with two distinct processes: a rapid loading process that was likely driven by an internal source and a slow loading process that was likely driven by solar wind. Each of the two loading processes could also individually lead to an unloading process. The rapid internal loading process lasts for ~ 1-2 hours; the solar wind driven loading process lasts for ~ 3-18 hours and the following unloading process lasts for ~1-3 hours. In this letter, we suggest three possible loadingunloading circulations, which are fundamental in understanding the role of solar wind in driving giant planetary magnetospheric dynamics.

GE SATURNE 41医用直线加速器偏转系统工作原理及典型故障分析

本文介绍了GE SATURNE 41型医用直线加速器偏转系统的构成和工作原理,同时分析了典型故障的排除方法。

A model of Saturn inferred from its measured gravitational field

We present an interior model of Saturn with an ice-rock core,a metallic region,an outer molecular envelope and a thin transition layer between the metallic and molecular regions.The shape of Saturn’s 1 bar surface is irregular and determined fully self-consistently by the required equilibrium condition.While the ice-rock core is assumed to have a uniform density,three different equations of state are adopted for the metallic,molecular and transition regions.The Saturnian model is constrained by its known mass,its known equatorial and polar radii,and its known zonal gravitational coefficients,J_（2n）,n=1,2,3.The model produces an ice-rock core with equatorial radius 0.203 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure surface;the core densityρ_c=10388.1 kgm^（3）corresponding to 13.06 Earth masses;and an analytical expression describing the Saturnian irregular shape of the 1-bar pressure level.The model also predicts the values of the higher-order gravitational coefficients,J_8,J_10 and J_12,for the hydrostatic Saturn and suggests that Saturn’s convective dynamo operates in the metallic region approximately defined by 0.2 R_S

Saturn＇s gravitational field induced by its equatorially antisymmetric zonal winds

The cloud-level zonal winds of Saturn are marked by a substantial equatorially antisymmetric component with a speed of about 50 m s^-1 which, if they are sufficiently deep, can produce measurable odd zonal gravitational coefficients △J2 k＋1, k = 1, 2, 3, 4. This study, based on solutions of the thermal-gravitational wind equation, provides a theoretical basis for interpreting the odd gravitational coefficients of Saturn in terms of its equatorially antisymmetric zonal flow. We adopt a Saturnian model comprising an ice-rock core, a metallic dynamo region and an outer molecular envelope. We use an equatorially antisymmetric zonal flow that is parameterized, confined in the molecular envelope and satisfies the solvability condition required for the thermal-gravitational wind equation. The structure and amplitude of the zonal flow at the cloud level are chosen to be consistent with observations of Saturn.We calculate the odd zonal gravitational coefficients △J2k＋1, k = 1, 2, 3, 4 by regarding the depth of the equatorially antisymmetric winds as a parameter. It is found that △J3 is-4.197 × 10^-8 if the zonal winds extend about 13 000 km downward from the cloud tops while it is-0.765 × 10^-8 if the depth is about 4000 km. The depth/profile of the equatorially antisymmetric zonal winds can eventually be estimated when the high-precision measurements of the Cassini Grand Finale become available.

The effect of the equatorially symmetric zonal winds of Saturn on its gravitational field

The penetration depth of Saturn’s cloud-level winds into its interior is unknown.A possible way of estimating the depth is through measurement of the effect of the winds on the planet’s gravitational field.We use a self-consistent perturbation approach to study how the equatorially symmetric zonal winds of Saturn contribute to its gravitational field.An important advantage of this approach is that the variation of its gravitational field solely caused by the winds can be isolated and identified because the leading-order problem accounts exactly for rotational distortion,thereby determining the irregular shape and internal structure of the hydrostatic Saturn.We assume that（i）the zonal winds are maintained by thermal convection in the form of non-axisymmetric columnar rolls and（ii）the internal structure of the winds,because of the Taylor-Proundman theorem,can be uniquely determined by the observed cloud-level winds.We calculate both the variation △J_n,n=2,4,6...of the axisymmetric gravitational coefficients J_n caused by the zonal winds and the non-axisymmetric gravitational coefficients △J_（nm） produced by the columnar rolls,where m is the azimuthal wavenumber of the rolls.We consider three different cases characterized by the penetration depth 0.36 R_S,0.2 R_S and 0.1 R_S,where R_S is the equatorial radius of Saturn at the 1-bar pressure level.We find that the high-degree gravitational coefficient （ J_（12）＋△J_（12）） is dominated,in all the three cases,by the effect of the zonal flow with ｜△J_（12）/J_（12）｜〉100%and that the size of the non-axisymmetric coefficientsdirectly reflects the depth and scale of the flow taking place in the Saturnian interior.

About Role of Electromagnetism to the Saturn Rings Origin<br/>—To the Unified Theory of the Planetary Rings Origin

Experimental data observation of the Saturn rings points to the conjecture that the particles constituting the rings may be superconductive. The main argument for this based on the fact that Saturn has a magnetic field and the temperature in its vicinity is low enough. Electromagnetic modeling shows the rings system emerges some time after appearance of the planetary magnetic field. Rings can be a result of the interaction of the superconducting carbon doped ice particles of the protoplanetary cloud with the nonuniform magnetic field. At the beginning all Keplerian orbits of the particles are located within protoplanetary cloud. After appearance of the magnetic field of Saturn, all iced particles demonstrate superconductivity and their orbits start to move to the magnetic equator plane where there is a minimum of magnetic energy. And then particles redistributed like iron particles nearby magnet on laboratory table forming system of rings and gaps. But rings particles are not stuck together because of Meissner phenomenon. The gravitational resonances and other interactions also play an important role and they help bring the order to the system of rings and gaps. It becomes to be clear why the rings appear only for the planets with magnetic field outside the asteroid belt such as Jupiter, Saturn, Uranus and Neptune. Inside the asteroid belt Sun’s heat is destroying superconductivity. Scenario of the rings creation for all planets could be the same. So we are coming to the unified theory of the rings origin. The presented model allows enriching the well-known theories that treat gravitational, mechanical, gas-plasma, dusty plasma and magnetohydrodynamic interactions in a consistent way.

Space Magnetism and Superconductivity: Diamagnetic Expulsion, Meissner Effect, Magnetic Pressure and Quantum Trapping Lead to the Origin and Stability of the Saturn Rings

Existence of the magnetic field of Saturn and the temperature around 70 - 100 K nearby of it bring us to the idea of diamagnetism and superconductivity of the rings particles. The rings could emerge from the icy particles moving on chaotic orbits around Saturn within protoplanetary cloud. After appearance of the magnetic field of Saturn all chaotic orbits of icy particles start to shift to the magnetic equator plane, where there is a minimum of the particles magnetic energy, due to diamagnetic force of expulsion like Meissner phenomenon. Each particle comes to the stable position preventing its own horizontal and vertical shift. Particles are locked within three-dimensional magnetic well due to Abrikosov quantum vortex phenomenon for superconductor. This mechanism is valid and it works even particles have a small fraction of superconductor. Final picture is similar to the picture of iron particles forms the same shape around a magnet on laboratory table. Any other phenomena like gravity resonances, dusty plasma and others may bring some peculiarities to the final picture of the rings. It follows that magnetic field of Saturn and low temperature around of it are the main reason for the rings origin and the rings is product of the early time of the magnetic field of Saturn appearance. Additional matter to the rings also may come from the frozen water particles generated from the Saturn sputniks geysers due to magnetic coupling between planet and satellites. The data of Cassini mission to Saturn rings are conforming suggested theory of their origin and existence.

Energy Gap in Saturn’s Rings

In this article, we consider, based on the super-diamagnetic model, the new problems of Saturn’s rings discovered by Cassini, such as: 1) anomalous purity of water ice;2) Saturn’s magnetic field alignment with the planet’s rotation axis;3) “ring rain” of the submicron particles;4) the deviation in the qualitative composition of the “rain” from the composition of the rings;5) “dirt” concentrated in the ring gaps;6) “plateaus” in Saturn’s C ring;7) age of the rings;8) roll-off in the spectrum of Saturn’s rings, and 9) “propellers” in Saturn’s A ring. Interpretation of Cassini’s observations of spectral roll-off in Saturn’s rings in the wavelength range from 100 micrometers to 0.5 mm is given. It was concluded that the substance of the rings could be in the superconducting state. An explanation of the Cassini spectral data is given using the hypothesis of the existence of a superconducting energy gap in the substance of rings.