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Journal articles on the topic 'Planetary Gravity'

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1

Lal, Ashwini Kumar. "On Planetary Electromagnetism and Gravity." International Journal of Astronomy and Astrophysics 01, no. 02 (2011): 62–66. http://dx.doi.org/10.4236/ijaa.2011.12009.

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2

Nerem, R. S. "Terrestrial and planetary gravity fields." Reviews of Geophysics 33 (1995): 469. http://dx.doi.org/10.1029/95rg00742.

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3

Scheffler, Guillermo, and Manuel Pulido. "Compensation between Resolved and Unresolved Wave Drag in the Stratospheric Final Warmings of the Southern Hemisphere." Journal of the Atmospheric Sciences 72, no. 11 (2015): 4393–411. http://dx.doi.org/10.1175/jas-d-14-0270.1.

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Abstract The role of planetary wave drag and gravity wave drag in the breakdown of the stratospheric polar vortex and its associated final warming in the Southern Hemisphere is examined using reanalyses from MERRA and a middle-atmosphere dynamical model. The focus of this work is on identifying the causes of the delay in the final breakdown of the stratospheric polar vortex found in current general circulation models. Sensitivity experiments were conducted by changing the launched momentum flux in the gravity wave drag parameterization. Increasing the launched momentum flux produces a delay of
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4

Hamouda, Samir A., Eman A. Alsslam Alfadeel, and Mohamed Belhasan Mohamed. "PLANETARY MAGNETIC FIELD AND GRAVITY IN THE SOLAR SYSTEM." International Journal of Research -GRANTHAALAYAH 5, no. 9 (2017): 145–51. http://dx.doi.org/10.29121/granthaalayah.v5.i9.2017.2224.

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Gravity plays a major role in the planetary formation and the development of the solar system. Gravity attraction is the essence of a power that holds and governs the universe; it makes the planets in the solar system revolve around the sun and the moons around their planets. Magnetic fields are also an important phenomenon in the solar system and beyond. Their causes are complex and have a variety of effects on their surroundings; they have become a critical tool for the exploration of solar system bodies. However, the study of the mechanisms of planets formation in the solar system is a diff
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Samir, A. Hamouda, A. Alsslam Alfadeel Eman, and Belhasan Mohamed Mohamed. "PLANETARY MAGNETIC FIELD AND GRAVITY IN THE SOLAR SYSTEM." International Journal of Research - Granthaalayah 5, no. 9 (2017): 145–51. https://doi.org/10.5281/zenodo.1002135.

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Gravity plays a major role in the planetary formation and the development of the solar system. Gravity attraction is the essence of a power that holds and governs the universe; it makes the planets in the solar system revolve around the sun and the moons around their planets. Magnetic fields are also an important phenomenon in the solar system and beyond. Their causes are complex and have a variety of effects on their surroundings; they have become a critical tool for the exploration of solar system bodies. However, the study of the mechanisms of planets formation in the solar system is a diff
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6

Campbell, Lucy J., and Theodore G. Shepherd. "Constraints on Wave Drag Parameterization Schemes for Simulating the Quasi-Biennial Oscillation. Part II: Combined Effects of Gravity Waves and Equatorial Planetary Waves." Journal of the Atmospheric Sciences 62, no. 12 (2005): 4196–205. http://dx.doi.org/10.1175/jas3617.1.

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Abstract This study examines the effect of combining equatorial planetary wave drag and gravity wave drag in a one-dimensional zonal mean model of the quasi-biennial oscillation (QBO). Several different combinations of planetary wave and gravity wave drag schemes are considered in the investigations, with the aim being to assess which aspects of the different schemes affect the nature of the modeled QBO. Results show that it is possible to generate a realistic-looking QBO with various combinations of drag from the two types of waves, but there are some constraints on the wave input spectra and
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7

Pérez-Cuéllar, G., and M. Sabido. "On planetary orbits in entropic gravity." Modern Physics Letters A 36, no. 08 (2021): 2150050. http://dx.doi.org/10.1142/s0217732321500504.

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Starting with an entropy that includes volumetric, area and length terms as well as logarithmic contributions, we derive the corresponding modified Newtonian gravity and derive the expression for planetary orbits. We calculate the shift of the perihelion of Mercury to find bounds to the parameters associated to the modified Newtonian gravity. We compare the parameter associated to the volumetric contribution in the entropy-area relationship with the value derived for galactic rotation curves and the value obtained from the cosmological constant.
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8

Fienga, A., J. Laskar, P. Kuchynka, C. Leponcin-Lafitte, H. Manche, and M. Gastineau. "Gravity tests with INPOP planetary ephemerides." Proceedings of the International Astronomical Union 5, S261 (2009): 159–69. http://dx.doi.org/10.1017/s1743921309990330.

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AbstractWe present here several gravity tests made with the latest INPOP08 planetary ephemerides. We first propose two methods to estimate the PPN parameter β and its correlated value, the Sun J2, and we discuss the correlation between the Sun J2 and the mass of the asteroid ring. We estimate a possible advance in the planet perihelia. We also show that no constant acceleration larger than 1/4 of the Pioneer anomaly is compatible with the observed motion of the planets in our Solar System.
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9

Khantadze, A. G., G. V. Jandieri, A. Ishimaru, T. D. Kaladze, and Zh M. Diasamidze. "Electromagnetic oscillations of the Earth's upper atmosphere (review)." Annales Geophysicae 28, no. 7 (2010): 1387–99. http://dx.doi.org/10.5194/angeo-28-1387-2010.

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Abstract. A complete theory of low-frequency MHD oscillations of the Earth's weakly ionized ionosphere is formulated. Peculiarities of excitation and propagation of electromagnetic acoustic-gravity, MHD and planetary waves are considered in the Earth's ionosphere. The general dispersion equation is derived for the magneto-acoustic, magneto-gravity and electromagnetic planetary waves in the ionospheric E- and F-regions. The action of the geomagnetic field on the propagation of acoustic-gravity waves is elucidated. The nature of the existence of the comparatively new large-scale electromagnetic
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10

Niksirat, Parna, Adriana Daca, and Krzysztof Skonieczny. "The effects of reduced-gravity on planetary rover mobility." International Journal of Robotics Research 39, no. 7 (2020): 797–811. http://dx.doi.org/10.1177/0278364920913945.

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One of the major challenges faced by planetary exploration rovers today is the negotiation of difficult terrain, such as fine granular regolith commonly found on the Moon and Mars. Current testing methods on Earth fail to account for the effect of reduced gravity on the soil itself. This work characterizes the effects of reduced gravity on wheel–soil interactions between an ExoMars rover wheel prototype and a martian soil simulant aboard parabolic flights producing effective martian and lunar gravitational accelerations. These experiments are the first to collect wheel–soil interaction imagery
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11

Pérez-Cuéllar, Gemma, and Miguel Sabido. "On Planetary Orbits, Ungravity and Entropic Gravity." Universe 10, no. 10 (2024): 386. http://dx.doi.org/10.3390/universe10100386.

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In previous works, entropic gravity and ungravity have been considered as possible solutions to the dark energy and dark matter problems. To test the viability of these models, modifications to planetary orbits are calculated for ungravity and different models of entropic gravity. Using the gravitational sector of unparticles, an equation for the contribution to the effect of orbital precession is obtained. We conclude that the estimated values for the ungravity parameters from planetary orbits are inconsistent with the values needed for the cosmological constant. The same ideas are explored f
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12

Baruteau, Clément, and Frédéric Masset. "Type I planetary migration in a self-gravitating disk." Proceedings of the International Astronomical Union 3, S249 (2007): 393–96. http://dx.doi.org/10.1017/s1743921308016888.

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AbstractWe investigate the impact of the disk self-gravity on type I migration. We first show that considering a planet migrating in a disk without self-gravity can lead to a significant overestimate of the migration rate. Unbiased drift rates can be obtained only if the planet and the disk feel the same gravitational potential. We then confirm that the disk gravity slightly accelerates type I migration.
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13

Macdonald, Malcolm, and Colin R. McInnes. "Spacecraft Planetary Capture Using Gravity-Assist Maneuvers." Journal of Guidance, Control, and Dynamics 28, no. 2 (2005): 365–69. http://dx.doi.org/10.2514/1.11866.

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14

McRonald, Angus D., and James E. Randolph. "Hypersonic maneuvering for augmenting planetary gravity assist." Journal of Spacecraft and Rockets 29, no. 2 (1992): 216–22. http://dx.doi.org/10.2514/3.26337.

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15

Ataiee, S., and W. Kley. "The role of disc torques in forming resonant planetary systems." Astronomy & Astrophysics 635 (March 2020): A204. http://dx.doi.org/10.1051/0004-6361/201936390.

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Context. The most accurate method for modelling planetary migration and hence the formation of resonant systems is using hydrodynamical simulations. Usually, the force (torque) acting on a planet is calculated using the forces from the gas disc and the star, while the gas accelerations are computed using the pressure gradient, the star, and the planet’s gravity, ignoring its own gravity. For a non-migrating planet the neglect of the disc gravity results in a consistent torque calculation while for a migrating case it is inconsistent. Aims. We aim to study how much this inconsistent torque calc
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16

Willmott, Andrew J., and Estanislao Gavilan Pascual-Ahuir. "Planetary and Gravity Waves in a Polar Basin." Journal of Physical Oceanography 47, no. 6 (2017): 1433–40. http://dx.doi.org/10.1175/jpo-d-16-0253.1.

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AbstractThe eigenfrequencies of freely propagating barotropic, divergent, planetary waves and gravity waves in a spherical polar cap are presented using an approximation in which full spherical geometry is retained in the derivation of the wave amplitude equation. Subsequently, the colatitude angle in the coefficients of the wave amplitude equation is fixed, thereby allowing the eigenvalue problem to be solved using analytical methods. The planetary wave frequencies are compared with published results that adopt the polar-plane approximation to solve the equivalent free-wave problem. Low-order
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17

Albers, John R., and Thomas Birner. "Vortex Preconditioning due to Planetary and Gravity Waves prior to Sudden Stratospheric Warmings." Journal of the Atmospheric Sciences 71, no. 11 (2014): 4028–54. http://dx.doi.org/10.1175/jas-d-14-0026.1.

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Abstract Reanalysis data are used to evaluate the evolution of polar vortex geometry, planetary wave drag, and gravity wave drag prior to split versus displacement sudden stratospheric warmings (SSWs). A composite analysis that extends upward to the lower mesosphere reveals that split SSWs are characterized by a transition from a wide, funnel-shaped vortex that is anomalously strong to a vortex that is constrained about the pole and has little vertical tilt. In contrast, displacement SSWs are characterized by a wide, funnel-shaped vortex that is anomalously weak throughout the prewarming perio
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18

Medvedev, Alexander S., and Erdal Yiğit. "Gravity Waves in Planetary Atmospheres: Their Effects and Parameterization in Global Circulation Models." Atmosphere 10, no. 9 (2019): 531. http://dx.doi.org/10.3390/atmos10090531.

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The dynamical and thermodynamical importance of gravity waves was initially recognized in the atmosphere of Earth. Extensive studies over recent decades demonstrated that gravity waves exist in atmospheres of other planets, similarly play a significant role in the vertical coupling of atmospheric layers and, thus, must be included in numerical general circulation models. Since the spatial scales of gravity waves are smaller than the typical spatial resolution of most models, atmospheric forcing produced by them must be parameterized. This paper presents a review of gravity waves in planetary a
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19

Parisi, Marzia. "The Case for Future Gravity Science Investigations at Saturn with a Planetary Orbiter." Planetary Science Journal 4, no. 8 (2023): 152. http://dx.doi.org/10.3847/psj/ace7ce.

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Abstract The next phase in the robotic exploration of the Saturnian system will target unresolved questions about the gas giant’s atmosphere, interior, magnetosphere, and rings that were left open by investigations on board the Cassini mission. Among these, we find gravity science objectives, which relate mainly to explaining the origin of the large wind-induced gravity signal and reconciling existing incongruities regarding the internal density distribution. Here we attempt to identify which future observations may yield additional information about Saturn’s internal mechanisms. We report on
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20

Prado, Antonio F. B. A. "Using Tethered Gravity-Assisted Maneuvers for Planetary Capture." Journal of Guidance, Control, and Dynamics 38, no. 9 (2015): 1852–56. http://dx.doi.org/10.2514/1.g001009.

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21

Mayr, H. G., J. G. Mengel, E. R. Talaat, H. S. Porter, and K. L. Chan. "Planetary-scale inertio gravity waves in the Mesosphere." Geophysical Research Letters 30, no. 23 (2003): n/a. http://dx.doi.org/10.1029/2003gl018376.

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22

Cai, XingShan, JunFeng Li, and ShengPing Gong. "Solar sailing trajectory optimization with planetary gravity assist." Science China Physics, Mechanics & Astronomy 58, no. 1 (2014): 1–11. http://dx.doi.org/10.1007/s11433-014-5567-1.

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23

Kunze, A. W. Gerhard. "Local harmonic analysis of planetary Doppler gravity data." Earth, Moon and Planets 32, no. 2 (1985): 173–81. http://dx.doi.org/10.1007/bf00054174.

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24

Sridharan, S., S. Sathishkumar, and K. Raghunath. "Rayleigh lidar observations of enhanced stratopause temperature over Gadanki (13.5° N, 79.2° E) during major stratospheric warming in 2006." Annales Geophysicae 27, no. 1 (2009): 373–79. http://dx.doi.org/10.5194/angeo-27-373-2009.

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Abstract. Rayleigh lidar observations of temperature structure and gravity wave activity were carried out at Gadanki (13.5° N, 79.2° E) during January–February 2006. A major stratospheric warming event occurred at high latitude during the end of January and early February. There was a sudden enhancement in the stratopause temperature over Gadanki coinciding with the date of onset of the major stratospheric warming event which occurred at high latitudes. The temperature enhancement persisted even after the end of the high latitude major warming event. During the same time, the UKMO (United King
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25

Campbell, Lucy J., and Theodore G. Shepherd. "Constraints on Wave Drag Parameterization Schemes for Simulating the Quasi-Biennial Oscillation. Part I: Gravity Wave Forcing." Journal of the Atmospheric Sciences 62, no. 12 (2005): 4178–95. http://dx.doi.org/10.1175/jas3616.1.

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Abstract Parameterization schemes for the drag due to atmospheric gravity waves are discussed and compared in the context of a simple one-dimensional model of the quasi-biennial oscillation (QBO). A number of fundamental issues are examined in detail, with the goal of providing a better understanding of the mechanism by which gravity wave drag can produce an equatorial zonal wind oscillation. The gravity wave–driven QBOs are compared with those obtained from a parameterization of equatorial planetary waves. In all gravity wave cases, it is seen that the inclusion of vertical diffusion is cruci
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26

Fruman, Mark D. "Equatorially Bounded Zonally Propagating Linear Waves on a Generalized β Plane". Journal of the Atmospheric Sciences 66, № 9 (2009): 2937–45. http://dx.doi.org/10.1175/2009jas2932.1.

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Abstract Meridionally confined zonally propagating wave solutions to the linear hydrostatic Boussinesq equations on a generalized equatorial β plane that includes the “nontraditional” Coriolis force terms associated with the poleward component of planetary rotation are calculated. Kelvin, Rossby, inertia–gravity, and mixed Rossby–gravity modes generalize from the traditional model with the dispersion relation unchanged. The effects of the nontraditional terms on all waves are the curving upward with latitude of the surfaces of constant phase and the equatorial trapping width of the solutions (
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27

Ito, Yoichiro. "Two-phase Motion in Hydrodynamic Counter-current Chromatography." Current Chromatography 7, no. 2 (2020): 76–81. http://dx.doi.org/10.2174/2213240606666190912161221.

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Background: Motion of the two mutually immiscible liquids in hydrodynamic countercurrent chromatographic systems is speculated based on the observation of their behavior in a closed coiled tube rotating in unit gravity. Materials and Methods: The experiment revealed an up and down pattern of four stages of twophase volume ratio occupied at the head end of the coil according to the rotation speed. These two-phase behaviors are comprehensively explained on the bases of interplay between the unit gravity and centrifugal force generated by rotation of the coil. This theory is successfully extended
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28

Shepherd, Theodore G., and Tiffany A. Shaw. "The Angular Momentum Constraint on Climate Sensitivity and Downward Influence in the Middle Atmosphere." Journal of the Atmospheric Sciences 61, no. 23 (2004): 2899–908. http://dx.doi.org/10.1175/jas-3295.1.

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Abstract It is shown that under reasonable assumptions, conservation of angular momentum provides a strong constraint on gravity wave drag feedbacks to radiative perturbations in the middle atmosphere. In the time mean, radiatively induced temperature perturbations above a given altitude z cannot induce changes in zonal mean wind and temperature below z through feedbacks in gravity wave drag alone (assuming an unchanged gravity wave source spectrum). Thus, despite the many uncertainties in the parameterization of gravity wave drag, the role of gravity wave drag in middle-atmosphere climate per
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29

Karlsson, Bodil, and Erich Becker. "How Does Interhemispheric Coupling Contribute to Cool Down the Summer Polar Mesosphere?" Journal of Climate 29, no. 24 (2016): 8807–21. http://dx.doi.org/10.1175/jcli-d-16-0231.1.

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Abstract Interhemispheric coupling is commonly associated with events of high planetary wave activity in the winter stratosphere triggering a heating of the polar mesopause region in the opposite hemisphere. Here, a more fundamental role that this mechanism plays in the absence of planetary wave variability is highlighted. This study focuses directly on the mesospheric part of the coupling chain, which is induced by the gravity wave drag in the winter mesosphere. To investigate the effect that the winter residual flow has on the summertime high-latitude upwelling, the Kühlungsborn Mechanistic
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30

Dwarkadas, Vikram V., and Stanley Owocki. "Radiatively Driven Winds and the Formation of Bipolar Planetary Nebulae." Symposium - International Astronomical Union 209 (2003): 467–70. http://dx.doi.org/10.1017/s0074180900209376.

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We study the role of radiatively driven winds in the formation of PNe. The modulation of these winds due to stellar rotation, and Von Zeipel gravity darkening, are both considered. Rotation produces a wind that is faster at the poles but denser at the equator. The Von Zeipel effect, which states that the stellar flux is proportional to the effective surface gravity, results in the inverse density distribution, giving a wind that is both faster and denser at the poles. Both these effects produce bipolar nebulae for large rotational velocities of the star.
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31

Tenzer, Robert, Ismael Foroughi, Christian Hirt, Pavel Novák, and Martin Pitoňák. "How to Calculate Bouguer Gravity Data in Planetary Studies." Surveys in Geophysics 40, no. 1 (2018): 107–32. http://dx.doi.org/10.1007/s10712-018-9504-0.

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32

Flokstra, J., R. Cuperus, R. J. Wiegerink, and M. C. van Essen. "A MEMS-based gravity gradiometer for future planetary missions." Cryogenics 49, no. 11 (2009): 665–68. http://dx.doi.org/10.1016/j.cryogenics.2008.12.019.

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33

MacLeod, Morgan, Antonija Oklopčić, Fabienne Nail, and Dion Linssen. "Streams and Bubbles: Tidal Shaping of Hydrodynamic Planetary Outflows." Astrophysical Journal 988, no. 1 (2025): 63. https://doi.org/10.3847/1538-4357/ade0b7.

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Abstract Planets, especially those close to their host stars, lose mass to atmospheric outflows, a process that is thought to shape the bimodal population of gaseous giant and rocky terrestrial exoplanets in close orbits. We model the hydrodynamic escape of planetary atmospheres in idealized, three-dimensional gas dynamic simulations in order to study their emergent morphology. As we vary the simulated system parameters, model outflows show a range of shapes from fast, isotropic outflows bounded by bow shocks to slower motion confined to thin streams. We show that a crucial factor is the role
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34

Scheeres, D. J. "The Dynamics of NEO Binary Asteroids." Proceedings of the International Astronomical Union 2, S236 (2006): 177–90. http://dx.doi.org/10.1017/s1743921307003213.

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AbstractThe dynamics of binary Near-Earth objects (NEO) are discussed and a simple model for the study of their dynamics is introduced. Main results on the motion and stability of binary asteroids are reviewed. The effect of perturbations external to the binary system, including solar gravity, solar radiation pressure, and planetary gravity, are considered.
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35

Liu, Zhenxing, Zhansheng Liu, and Xiangyu Yu. "Dynamic modeling and response of a spur planetary gear system with journal bearings under gravity effects." Journal of Vibration and Control 24, no. 16 (2017): 3569–86. http://dx.doi.org/10.1177/1077546317707878.

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This paper focuses on the modeling method and the gravity-induced dynamic response of a spur planetary gear system with journal bearings. The lumped-parameter model of a planetary gear system with journal bearings is established. Both contact on drive-side and back-side of the tooth are considered simultaneously. Linear and nonlinear bearing force models are introduced into the system model separately to take the planet bearing oil-film forces into account. A demonstration is given to show the adopted nonlinear oil-film force model is still valid for the lubrication of support for planet gears
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36

Goldreich, Peter. "Puzzles and Prospects in Planetary Ring Dynamics." Symposium - International Astronomical Union 152 (1992): 65–73. http://dx.doi.org/10.1017/s0074180900090951.

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I outline some of the main processes that shape planetary rings. Then I focus on two outstanding issues, the role of self-gravity in the precession of narrow rings and the dynamics of Neptune's arcs. By airing these well-defined but unsolved problems, I hope to encourage others to join me in the quest for their solutions.
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37

Wang, Jessie. "Law of Gravity Blurred by Perturbed Planetary Orbits for Alien Observers." Journal of Physics: Conference Series 2287, no. 1 (2022): 012039. http://dx.doi.org/10.1088/1742-6596/2287/1/012039.

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Abstract The Fermi paradox is the contradiction between the high probability for aliens and its lack of evidence. This is perhaps the most significant of all questions in astronomy. Nowadays, thousands of exoplanets have been detected, providing us more information directly from alien planets to revisit Fermi paradox. Over recent years, the detection of habitable exoplanets has grown rapidly, and most of them in multi-planet system with fairly compact structures, which is partly due to our observational techniques. In such systems, planets’ orbits are significantly perturbed by gravitational i
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38

Ern, Manfred, Quang Thai Trinh, Martin Kaufmann, et al. "Satellite observations of middle atmosphere gravity wave absolute momentum flux and of its vertical gradient during recent stratospheric warmings." Atmospheric Chemistry and Physics 16, no. 15 (2016): 9983–10019. http://dx.doi.org/10.5194/acp-16-9983-2016.

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Abstract. Sudden stratospheric warmings (SSWs) are circulation anomalies in the polar region during winter. They mostly occur in the Northern Hemisphere and affect also surface weather and climate. Both planetary waves and gravity waves contribute to the onset and evolution of SSWs. While the role of planetary waves for SSW evolution has been recognized, the effect of gravity waves is still not fully understood, and has not been comprehensively analyzed based on global observations. In particular, information on the gravity wave driving of the background winds during SSWs is still missing.We i
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39

Harrison, H. Ron. "Basics of post Newtonian gravity- a new simpler approach." Aeronautics and Aerospace Open Access Journal 8, no. 1 (2024): 54–56. http://dx.doi.org/10.15406/aaoaj.2024.08.00193.

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Galileo studied bodies falling under gravity and Tycho Brahe made extensive astronomical observations which led Kepler to formulate his three famous laws of planetary motion. All these observations were of relative motion. This led Newton to propose his theory of gravity, which could just as well have been expressed in a form that does not involve the concept of force.
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40

Rubincam, David Parry, B. Fong Chao, Kenneth H. Schatten, and William W. Sager. "Non-Newtonian gravity or gravity anomalies?" Eos, Transactions American Geophysical Union 69, no. 50 (1988): 1636. http://dx.doi.org/10.1029/88eo01233.

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41

Erwin, Andrew, Leandro A. N. de Paula, Nicholas C. Schmerr, et al. "Brownian Noise and Temperature Sensitivity of Long-Period Lunar Seismometers." Bulletin of the Seismological Society of America 111, no. 6 (2021): 3065–75. http://dx.doi.org/10.1785/0120210072.

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ABSTRACT As long-period ground motion holds the key to understanding the interior of the Earth’s Moon, reducing long-period noise sources will be an essential area of focus in the design of future lunar seismometers. For the proposed Lunar Geophysical Network (LGN), the International Lunar Network (ILN) Science Definition Team specifies that an LGN enabling seismometer will need to be more sensitive than any previous seismometer at frequencies below 1 Hz. In an effort toward lowering the seismometer noise floor for lunar geophysical missions, we evaluate the 1/f Brownian noise and the temperat
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42

Križan, Peter. "Assessing the role of planetary and gravity waves in the vertical structure of ozone over midlatitudinal Europe." Annales Geophysicae 37, no. 4 (2019): 525–33. http://dx.doi.org/10.5194/angeo-37-525-2019.

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Abstract. Planetary and gravity waves play an important role in the dynamics of the atmosphere. They are present in the atmospheric distribution of temperature, wind, and ozone content. These waves are detectable also in the vertical profile of ozone and they cause its undulation. One of the structures occurring in the vertical ozone profile is laminae, which are narrow layers of enhanced or depleted ozone concentrations in the vertical ozone profile. They are connected with the total amount of ozone in the atmosphere and with the activity of the planetary and gravity waves. The aim of this pa
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43

Barriot, J. P., and G. Balmino. "Estimation of local planetary gravity fields using line of sight gravity data and an integral operator." Icarus 99, no. 1 (1992): 202–24. http://dx.doi.org/10.1016/0019-1035(92)90183-8.

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44

Borovin, Gennadii Konstantinovich, Yuri Filippovich Golubev, Aleksei Vasilievich Grushevskii, and Andrei Georgievich Tuchin. "Perturbation hollow spheres and planetary perturbation rings pursuant to the gravity assists scattering in the Solar system." Mathematica Montisnigri 55 (2022): 67–73. http://dx.doi.org/10.20948/mathmontis-2022-55-7.

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One of the types of gravitational scattering in the Solar system within the framework of the model of the circular restricted three-body problem (CR3BP) are the gravity assist maneuvers of the "particles of insignificant mass" (spacecraft, asteroids, comets, etc.). For their description, a physical analogy with the beam scattering of charged α-particles in a Coulomb field is useful. However, unlike the scattering of charged particles, there are external restrictions for the possibility of gravity assists executing related from the restricted size of planet's sphere of influence. At the same ti
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Lin, Zifan, Sara Seager, and Benjamin P. Weiss. "Interior and Gravity Field Models for Uranus Suggest a Mixed-composition Interior: Implications for the Uranus Orbiter and Probe." Planetary Science Journal 6, no. 2 (2025): 27. https://doi.org/10.3847/psj/ada124.

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Abstract The interior composition and structure of Uranus are ambiguous. It is unclear whether Uranus is composed of fully differentiated layers dominated by an icy mantle or has smooth compositional gradients. The Uranus Orbiter and Probe (UOP), the next NASA flagship mission prioritized by the Planetary Science and Astrobiology Survey 2023–2032, will constrain the planet's interior by measuring its gravity and magnetic fields. To characterize the Uranian interior, here we present CORGI, a newly developed planetary interior and gravity model. We confirm that high degrees of mixing are require
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Liu, Jiachen, Jun Yang, Yixiao Zhang, and Zhihong Tan. "Convection and Clouds under Different Planetary Gravities Simulated by a Small-domain Cloud-resolving Model." Astrophysical Journal 944, no. 1 (2023): 45. http://dx.doi.org/10.3847/1538-4357/aca965.

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Abstract In this study, we employ a cloud-resolving model to investigate how gravity influences convection and clouds in a small-domain (96 × 96 km) radiative–convective equilibrium. Our experiments are performed with a horizontal grid spacing of 1 km, which can resolve large (>1 km2) convective cells. We find that under a given stellar flux, sea surface temperature increases with decreasing gravity. This is because a lower-gravity planet has larger water vapor content and more clouds, resulting in a larger clear-sky greenhouse effect and a stronger cloud warming effect in the small domain.
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Napiwotzki, R. "Central Stars of Old Planetary Nebulae." Symposium - International Astronomical Union 155 (1993): 88. http://dx.doi.org/10.1017/s0074180900170184.

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During a program for the observation of central stars of old planetary nebulae 29 stars are classified until now. Most of them (22) are belonging to the hydrogen-rich sequence and resemble either high-gravity sdO stars or white dwarfs (14 DAOs, 3 DAs). 3 are hydrogen-deficient PG 1159 stars, and also 3 are hybrid type stars Further 3 CPN are close binaries, whose evolution has been certainly influenced by this circumstance. A complete list of so far observed objects is given in Napiwotzki (1992).
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Früh, W. G. "Using magnetic fluids to simulate convection in a central force field in the laboratory." Nonlinear Processes in Geophysics 12, no. 6 (2005): 877–89. http://dx.doi.org/10.5194/npg-12-877-2005.

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Abstract. Large-scale convection in planetary or stellar interiors plays a significant role but it is difficult to reproduce the central force field of those systems in experimental studies. A technique to approximate a central force field through the magnetic field from magnets acting on a magnetic liquid is presented. The thermomagnetic convection in a spherical shell filled with a magnetic liquid is analyzed in the context of a terrestrial laboratory using a 2D Finite Element model. Two configurations of magnetic fields were investigated, one resulting in a radially decreasing force field,
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Runyon, Kirby D., Daniel D. Durda, Viliam Klein, et al. "Methods for Experimental Planetary Geology in Reduced-gravity Parabolic Flight: A Case Study of Researching Impact Crater Ejecta." Planetary Science Journal 6, no. 3 (2025): 58. https://doi.org/10.3847/psj/adb74c.

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Abstract Geologists have long conducted laboratory experiments to offer a controlled environment for understanding processes that occur in nature and linking those processes with natural geologic landforms. And, for over 70 yr, pilots and researchers have accessed reduced-gravity and microgravity conditions by flying aircraft in parabolic arc-shaped trajectories. However, only recently (technically since the 1980s but practically since the 2010s) has experimental geology begun to find a home in reduced-gravity flight with application to the solid-bodied worlds of the solar system. The methodol
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LIU, Zhen, Haibo GAO, and Zongquan DENG. "Design of the Low Gravity Simulation System for Planetary Rovers." Robot 35, no. 6 (2013): 750. http://dx.doi.org/10.3724/sp.j.1218.2013.00750.

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