Увійти

Готові списки джерел за темами / Planetary bodies / Статті в журналах

Статті в журналах з теми "Planetary bodies"

Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Planetary bodies.

Автор: Grafiati

Опубліковано: 8 червня 2024

Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями

Оберіть тип джерела:

Ознайомтеся з топ-50 статей у журналах для дослідження на тему "Planetary bodies".

Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.

Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.

Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.

1

Hu, H., and B. Wu. "PLANETARY3D: A PHOTOGRAMMETRIC TOOL FOR 3D TOPOGRAPHIC MAPPING OF PLANETARY BODIES." ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences IV-2/W5 (May 29, 2019): 519–26. http://dx.doi.org/10.5194/isprs-annals-iv-2-w5-519-2019.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

<p><strong>Abstract.</strong> Planetary remote sensing images are the primary datasets for high-resolution topographic mapping and modeling of the planetary surfaces. However, unlike the mapping satellites for Earth observations, cameras onboard the planetary satellites generally present special imaging geometries and configurations, which makes the stereo photogrammetric process difficult and requires a large number of manual interactions. At the Hong Kong Polytechnic University, we developed a unified photogrammetric software system, namely Planetary3D, for 3D topographic mapping modeling of various planetary bodies using images collected by various sensors. Planetary3D consists of three modules, including: (1) the pre-processing module to deliver standardized image products, (2) the bundle adjustment module to alleviate the inconsistencies between the images and possibly the reference frame, and (3) the dense image matching module to create pixel-wise image matches and produce high quality topographic models. Examples of using three changeling datasets, including the MRO CTX, MRO HiRISE and Chang’E-2 images, have revealed that the automatic pipeline of Planetary3D can produce high-quality digital elevation models (DEMs) with favorable performances. Notably, the notorious jitter effects visible on HiRISE images can be effectively removed and good consistencies with the reference DEMs are found for the test datasets by the Planetary3D pipeline.</p>

2

Kadish, Jon, J. R. Barber, P. D. Washabaugh, and D. J. Scheeres. "Stresses in accreted planetary bodies." International Journal of Solids and Structures 45, no. 2 (January 2008): 540–50. http://dx.doi.org/10.1016/j.ijsolstr.2007.08.008.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

3

Connolly, William E. "Bodies, Microbes and the Planetary." Theory & Event 21, no. 4 (October 2018): 962–67. http://dx.doi.org/10.1353/tae.2018.0058.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

4

Cockell, Charles S., and Gerda Horneck. "Planetary parks—formulating a wilderness policy for planetary bodies." Space Policy 22, no. 4 (November 2006): 256–61. http://dx.doi.org/10.1016/j.spacepol.2006.08.006.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

5

Kotliarov, I. D. "Classification of celestial bodies within planetary systems." Moscow University Physics Bulletin 63, no. 6 (December 2008): 416–19. http://dx.doi.org/10.3103/s0027134908060118.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

6

Melosh, H. J. "Ejection of rock fragments from planetary bodies." Geology 13, no. 2 (1985): 144. http://dx.doi.org/10.1130/0091-7613(1985)13<144:eorffp>2.0.co;2.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

7

Lin, Yucong, Melissa Bunte, Srikanth Saripalli, James Bell, and Ronald Greeley. "Autonomous volcanic plume detection on planetary bodies." Acta Astronautica 97 (April 2014): 151–63. http://dx.doi.org/10.1016/j.actaastro.2013.11.029.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

8

Binzel, Richard P. "Small bodies looming large in planetary science." Nature Astronomy 3, no. 4 (April 2019): 282–83. http://dx.doi.org/10.1038/s41550-019-0747-6.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

9

Skripka, V. L., and L. H. Minyazeva. "Planetary rock-breaking bodies and horizontal drilling." Proceedings of higher educational establishments. Geology and Exploration, no. 5 (February 5, 2023): 86–93. http://dx.doi.org/10.32454/0016-7762-2022-64-5-86-93.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Background. The article considers one of the variants of the original planetary drilling organ, in which used multiple impacts on the mass to be destroyed. This makes it possible to improve the methods of sinking inclined and horizontal wells by significantly reducing the required feed force and reducing the energy intensity of bottom hole destructionAim. To investigate drilling methods and tools, which can be used to significantly reduce the radius of changes in drilling direction when creating inclined and horizontal wellbores.Materials and methods. An analysis of patent information and its experimental verification under laboratory conditions.Results. The main advantage of the analyzed drilling bodies is associated with their rock-breaking ability due to multiple shock pulses directed at an angle to the face surface. This allows the energy intensity of fracture and the required feed force in the axial direction to be significantly reduced, thus providing for larger wellbore diameters. A reduction in the axial length of the drilling body leads to a decrease in the radius of changes in drilling direction, thereby contributing to improved technologies of wellbore drilling, in particular, when creating horizontal wellbores.Conclusion. Planetary rock-breaking bodies implement quasi-dynamic rock destruction by multiple shock pulses and spalling off rock pieces from an automatically formed wavy face surface. On this basis, modern technologies of drilling inclined and horizontal wellbores can be improved.

10

Visser, R. G., C. W. Ormel, C. Dominik, and S. Ida. "Spinning up planetary bodies by pebble accretion." Icarus 335 (January 2020): 113380. http://dx.doi.org/10.1016/j.icarus.2019.07.014.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

11

Minglibayev, M. Zh, and A. B. Kosherbayeva. "EQUATIONS OF PLANETARY SYSTEMS MOTION." SERIES PHYSICO-MATHEMATICAL 6, no. 334 (December 15, 2020): 53–60. http://dx.doi.org/10.32014/2020.2518-1726.97.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The study of the dynamically evolution of planetary systems is very actually in relation with findings of exoplanet systems. free spherical bodies problem is considered in this paper, mutually gravitating according to Newton's law, with isotropically variable masses as a celestial-mechanical model of non-stationary exoplanetary systems. The dynamic evolution of planetary systems is learned, when evolution's leading factor is the masses' variability of gravitating bodies themselves. The laws of the bodies' masses varying are assumed to be known arbitrary functions of time. When doing so the rate of varying of bodies' masses is different. The planets' location is such that the orbits of planets don't intersect. Let us treat this position of planets is preserve in the evolution course. The motions are researched in the relative coordinates system with beginning in the center of the parent star, axes that are parallel to corresponding axes of the absolute coordinates system. The canonical perturbation theory is used on the base aperiodic motion over the quasi-canonical cross-section. The bodies evolution is studied in the osculating analogues of the second system of canonical Poincare elements. The canonical equations of perturbed motion in analogues of the second system of canonical Poincare elements are convenient for describing the planetary systems dynamic evolution, when analogues of eccentricities and analogues of inclinations of orbital plane are sufficiently small. It is noted that to obtain an analytical expression of the perturbing function main part through canonical osculating Poincare elements using computer algebra is preferably. If in expansions of the main part of perturbing function is constrained with precision to second orders including relatively small quantities, then the equations of secular perturbations will obtained as linear non-autonomous system. This circumstance meaningful makes much easier to study the non-autonomous canonical system of differential equations of secular perturbations of considering problem.

12

ten Kate, I. L., and M. Reuver. "PALLAS: Planetary Analogues Laboratory for Light, Atmosphere, and Surface Simulations." Netherlands Journal of Geosciences - Geologie en Mijnbouw 95, no. 2 (June 15, 2015): 183–89. http://dx.doi.org/10.1017/njg.2015.19.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractHumankind has been interested in space throughout the ages and studies of the universe and our own solar system have been ongoing since the first observations of celestial bodies. In the current era space exploration has provided in situ data for the different bodies in our solar system. To fully comprehend the underlying processes occurring in these bodies, missions and telescope observations are, however, not sufficient and additional modelling studies, both numerical and analogue, are necessary. In this paper we present a new facility specifically designed to experimentally study organic compounds under simulated planetary (sub)surface conditions on rocky bodies in our solar system: PALLAS, the Planetary Analogues Laboratory for Light, Atmosphere, and Surface Simulations. We give an overview of planetary conditions that can be simulated in this facility and that are known to affect organic compounds: radiation, atmospheric composition, temperature and surface composition.

13

Rietmeijer, Frans J. M. "A model for diagenesis in proto-planetary bodies." Nature 313, no. 6000 (January 1985): 293–94. http://dx.doi.org/10.1038/313293a0.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

14

Haghighipour, Nader. "Super-Earths: a new class of planetary bodies." Contemporary Physics 52, no. 5 (September 2011): 403–38. http://dx.doi.org/10.1080/00107514.2011.598370.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

15

Ibadov, Subhon, and Firuz S. Ibodov. "Explosive evolution of small bodies in planetary atmospheres." Proceedings of the International Astronomical Union 9, S310 (July 2014): 162–63. http://dx.doi.org/10.1017/s1743921314008126.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractThe entry of small celestial bodies such as cometary nuclei, asteroids and their large fragments, into a planetary atmosphere is accompanied by an “explosion”, i.e., sudden rise in brightness and the generation of a “blast” shock wave, like the 2013 Chelyabinsk event. Fully analytic approach to the phenomenon is developed taking into account aerodynamic crushing of the body and transversal expansion of the crushed mass, that leads to impulse generation of hot plasma and a “blast” shock wave in the thin “exploding” layer.

16

GIRISH, T. "Nighttime operation of photovoltaic systems in planetary bodies." Solar Energy Materials and Solar Cells 90, no. 6 (April 14, 2006): 825–31. http://dx.doi.org/10.1016/j.solmat.2005.04.018.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

17

WETHERILL, G. W. "Occurrence of Earth-Like Bodies in Planetary Systems." Science 253, no. 5019 (August 2, 1991): 535–38. http://dx.doi.org/10.1126/science.253.5019.535.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

18

Wang, X., J. Schwan, H. W. Hsu, E. Grün, and M. Horányi. "Dust charging and transport on airless planetary bodies." Geophysical Research Letters 43, no. 12 (June 25, 2016): 6103–10. http://dx.doi.org/10.1002/2016gl069491.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

19

Matsuyama, Isamu, and Francis Nimmo. "Tectonic patterns on reoriented and despun planetary bodies." Icarus 195, no. 1 (May 2008): 459–73. http://dx.doi.org/10.1016/j.icarus.2007.12.003.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

20

Brigham, Jonee Kulman. "Integrated Bodies: Language, Art, and Infrastructure in Planetary Health Education." Creative Nursing 27, no. 4 (November 1, 2021): 269–72. http://dx.doi.org/10.1891/cn-2021-0036.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The Planetary Health Education Framework recognizes the interdependence of human health and the health of planetary ecosystems, and centers its guidance on the paradigm of human interconnection within nature. Through the author's scholarship and art, she addresses this “paradigm work” to heal the human-nature divide. This essay explores ideas for the role of language, art, and infrastructure in supporting Planetary Health Education using the example of Earth Systems Journey, which is both an art form and a curriculum model for experiential, art-led environmental education about human integration within nature.

21

Wang, Y., R. B. Dong, D. N. C. Lin, and X. W. Liu. "Origin of debris disks and the supply of metals in DZ white dwarfs." Proceedings of the International Astronomical Union 3, S249 (October 2007): 389–92. http://dx.doi.org/10.1017/s1743921308016876.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractWe discuss the dynamical evolution of minor planetary bodies in the outer regions of planetary systems around the progenitors of DZ white dwarfs. We show that during the planetary-nebula phase of these stars, mass loss can lead to the expansion of all planetary bodies. The orbital eccentricity of the minor bodies, as relics of planetesimals, may be largely excited by the perturbation due to both gas drag effects and nearby gas giant planets. Some of these bodies migrate toward the host star, while others are scattered out of the planetary system. The former have modest probability of being captured by the sweeping secular resonances of giant planets, and induced to migrate toward the host star. When they venture close to their host stars, their orbits are tidally circularized so that they form compact disks where they may undergo further collisionally driven evolution. During the subsequent post main sequence evolution of their host stars, this process may provide an avenue which continually channels heavy elements onto the surface of the white dwarfs. We suggest that this scenario provides an explanation for the recently discovered Calcium line variation in G29-38.

22

Bischoff, Adolf, and Dieter Stöffler. "Shock metamorphism as a fundamental process in the evolution of planetary bodies: Information from meteorites." European Journal of Mineralogy 4, no. 4 (August 11, 1992): 707–56. http://dx.doi.org/10.1127/ejm/4/4/0707.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

23

Williams, Iwan P., Edward L. G. Bowell, Mikhail Ya Marov, Guy J. Consolmagno, Michael F. A'Hearn, Alan P. Boss, Dale P. Cruikshank, Anny-Chantal Levasseur-Regord, David Morrison, and Christopher G. Tinney. "DIVISION III: PLANETARY SYSTEM SCIENCES." Proceedings of the International Astronomical Union 3, T26B (December 2007): 111–17. http://dx.doi.org/10.1017/s1743921308023764.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Division III gathers astronomers engaged in the study of a comprehensive range of phenomena in the solar system and its bodies, from the major planets via comets to meteorites and interplanetary dust.

24

Bowell, Edward L. G., Karen J. Meech, Iwan P. Williams, Alan P. Boss, Guy J. Consolmagno, Régis Courtin, Julio A. Fernández, et al. "DIVISION III: PLANETARY SYSTEMS SCIENCES." Proceedings of the International Astronomical Union 4, T27A (December 2008): 149–53. http://dx.doi.org/10.1017/s1743921308025398.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

25

Melita, M. D., and A. Brunini. "The evolution of the Kuiper belt during the formation of the outer planets." International Astronomical Union Colloquium 173 (1999): 37–44. http://dx.doi.org/10.1017/s0252921100031213.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractA self-consistent study of the formation of planetary bodies beyond the orbit of Saturn and the evolution of Kuiper disks is carried out by means of an N-body code where accretion and gravitational encounters are considered. This investigation is focused on the aggregation of massive bodies in the outer planetary region and on the consequences of such process in the corresponding cometary belt. We study the link between the bombardment of massive bodies and mass depletion and eccentricity excitation.

26

Tichá, Jana, Brian G. Marsden, Daniel Green, Rita M. Schulz, Michael F. A'Hearn, Julio A. Fernandez, Pamela Kilmartin, et al. "DIVISION III / WG: COMMITTEE SMALL BODIES NOMENCLATURE." Proceedings of the International Astronomical Union 3, T26B (December 2007): 118–19. http://dx.doi.org/10.1017/s1743921308023776.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

27

Minglibayev, M. Zh, and A. B. Kosherbayeva. "DIFFERENTIAL EQUATIONS OF PLANETARY SYSTEMS." REPORTS 2, no. 330 (April 15, 2020): 14–20. http://dx.doi.org/10.32014/10.32014/2020.2518-1483.26.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

In this article will be considered many spherical bodies problem with variable masses, varying non-isotropic at different rates as celestial-mechanical model of non-stationary planetary systems. In this article were obtained differential equations of motions of spherical bodies with variable masses to reach purpose exploration of evolution planetary systems. The scientific importance of the work is exploration to the effects of masses’ variability of the dynamic evolution of the planetary system for a long period of time. According to equation of Mescherskiy, we obtained differential equations of motions of planetary systems in the absolute coordinates system and the relative coordinates system. On the basis of obtained differential equations in the relative coordinates system, we derived equations of motions in osculating elements in form of Lagrange's equations and canonically equations in osculating analogs second systems of Poincare's elements on the base aperiodic motion over the quasi-canonical cross- section.

28

Singh, Surendra V., Haritha Dilip, Jaya K. Meka, Vijay Thiruvenkatam, Vishakantaiah Jayaram, Mariyappan Muruganantham, Vijayan Sivaprahasam, et al. "New Signatures of Bio-Molecular Complexity in the Hypervelocity Impact Ejecta of Icy Moon Analogues." Life 12, no. 4 (March 30, 2022): 508. http://dx.doi.org/10.3390/life12040508.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Impact delivery of prebiotic compounds to the early Earth from an impacting comet is considered to be one of the possible ways by which prebiotic molecules arrived on the Earth. Given the ubiquity of impact features observed on all planetary bodies, bolide impacts may be a common source of organics on other planetary bodies both in our own and other solar systems. Biomolecules such as amino acids have been detected on comets and are known to be synthesized due to impact-induced shock processing. Here we report the results of a set of hypervelocity impact experiments where we shocked icy mixtures of amino acids mimicking the icy surface of planetary bodies with high-speed projectiles using a two-stage light gas gun and analyzed the ejecta material after impact. Electron microscopic observations of the ejecta have shown the presence of macroscale structures with long polypeptide chains revealed from LCMS analysis. These results suggest a pathway in which impact on cometary ices containing building blocks of life can lead to the synthesis of material architectures that could have played a role in the emergence of life on the Earth and which may be applied to other planetary bodies as well.

29

Yeo, Li Hsia, Xu Wang, Jan Deca, Hsiang-Wen Hsu, and Mihály Horányi. "Dynamics of electrostatically lofted dust on airless planetary bodies." Icarus 366 (September 2021): 114519. http://dx.doi.org/10.1016/j.icarus.2021.114519.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

30

Dumoulin, C., O. Čadek, and G. Choblet. "Predicting surface dynamic topographies of stagnant lid planetary bodies." Geophysical Journal International 195, no. 3 (October 3, 2013): 1494–508. http://dx.doi.org/10.1093/gji/ggt363.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

31

Neto-Lima, J., M. Fernández-Sampedro, and O. Prieto-Ballesteros. "High Pressure Serpentinization Catalysed by Awaruite in Planetary Bodies." Journal of Physics: Conference Series 950 (October 2017): 042041. http://dx.doi.org/10.1088/1742-6596/950/4/042041.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

32

Vaitekhovich, P. E., D. V. Semenenko, and D. V. Yukhnevich. "Motion specifics of grinding bodies in vertical planetary mills." Chemical and Petroleum Engineering 45, no. 7-8 (July 2009): 395–401. http://dx.doi.org/10.1007/s10556-009-9199-7.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

33

Cole, G. H. A. "Concerning the occurrence of water in the planetary bodies." Surveys in Geophysics 8, no. 4 (December 1986): 439–57. http://dx.doi.org/10.1007/bf01903950.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

34

Ziglina, I. N., and O. Yu Schmidt. "Stochastic Behaviour of Planetary Orbits During the Accumulation Process." International Astronomical Union Colloquium 132 (1993): 137–48. http://dx.doi.org/10.1017/s025292110006601x.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractThe evolution of orbital elements of a growing planet during the accumulation process is considered. The planetary orbit undergoes perturbations because of random encounters and collisions with bodies of its accretion zone and also because of gravitational interaction with an already formed massive planet (“Jupiter”). The mass and velocity distributions of the swarm bodies are assumed to be given time-dependent functions. The Fokker-Planck equation describing the behaviour of the distribution function of orbital elements of the growing planet is worked out and solved. The present mean values of the eccentricities and inclinations of orbits of the terrestrial planets can be explained in the case of their accumulation from a single swarm of bodies with mean mass ~ 10−2 M⊕ and with mean eccentricities and inclinations ~ 0.2.

35

Englert, Peter A. J. "Planetary gamma ray spectrometry: remote sensing of elemental abundances." Proceedings in Radiochemistry 1, no. 1 (September 1, 2011): 349–55. http://dx.doi.org/10.1524/rcpr.2011.0062.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract Planetary gamma ray spectrometry is a form of nuclear spectroscopy applied remotely to provide geochemical maps of planetary bodies. From early developments it has by now become a standard modality of planetary exploration. Basic and applied nuclear science has made significant contributions to the advancement of planetary gamma ray spectrometry, as outlined in this methodological and historical assessment.

36

Sarid, Gal, Sarah T. Stewart, and Zoë M. Leinhardt. "Erosive Hit-and-Run Impact Events: Debris Unbound." Proceedings of the International Astronomical Union 10, S318 (August 2015): 9–15. http://dx.doi.org/10.1017/s1743921315009679.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractErosive collisions among planetary embryos in the inner solar system can lead to multiple remnant bodies, varied in mass, composition and residual velocity. Some of the smaller, unbound debris may become available to seed the main asteroid belt. The makeup of these collisionally produced bodies is different from the canonical chondritic composition, in terms of rock/iron ratio and may contain further shock-processed material. Having some of the material in the asteroid belt owe its origin from collisions of larger planetary bodies may help in explaining some of the diversity and oddities in composition of different asteroid groups.

37

Beaugé, C., and S. J. Aarseth. "N-body simulations of planetary formation." Monthly Notices of the Royal Astronomical Society 245, no. 1 (July 1, 1990): 30. http://dx.doi.org/10.1093/mnras/245.1.30.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Summary We have performed numerical simulations of the last stage of terrestrial planetary formation using an N-body code similar to that of Lecar & Aarseth. An improved treatment of collisions has been applied, which allows fragmentation and cratering, as well as accretion. Initial models consist of 200 bodies of total mass 2.3 x 1028 g, distributed in a two-dimensional ring of size 1 au with initial circular orbits about the Sun. Planetary embryos begin to form by accretion in the early stages when the relative velocities are small. This growth is slowed down by the fragmentation process, which occurs when the typical eccentricities have reached ⋍ 0.04. Eventually, a small number of massive embryos emerge, and subsequently accrete nearly all the fragments. Final configurations of three different models yield four principal bodies with moderate eccentricities on a time-scale of ⋍ 5 x 105 yr (equivalent to ∽ 108 yr in a 3D model), and the corresponding parameters are qualitatively similar to those of the terrestrial planets.

38

Wilson, Alfred, Andrew Walker, Dario Alfè, and Chris Davies. "Solid-Liquid Interactions in Deep Planetary Interiors." Astronomy & Geophysics 65, no. 3 (June 1, 2024): 3.18–3.22. http://dx.doi.org/10.1093/astrogeo/atae036.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Abstract Alfred Wilson, Andrew Walker, Dario Alfè and Chris Davies report on a meeting bringing together experimental, theoretical, and observational studies of the deep mantles and cores of terrestrial bodies

39

Bergin, Edwin, Merel van’t Hoff, and Jes Jørgensen. "Searching For the t=0 of Planetary System Formation." EPJ Web of Conferences 265 (2022): 00043. http://dx.doi.org/10.1051/epjconf/202226500043.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

The composition of bodies in the solar system points to strong gradients in the volatile content within solid bodies hinting at the presence of gas-ice transitions across sublimation fronts in the young formative stages when the gas-rich disk was present. Terrestrial worlds are constructed out of the disk solids which are primarily silicate and water, but might also contain a significant fraction of organic material. These refractory organics are the source of carbon to Earth-like worlds, but have the potential to be destroyed if temperatures exceed 300-500 K (depending on pressure). These temperatures are most readily prevalent during the early stages of planetary system formation where the seeds of terrestrial worlds are potentially assembled. Here we present an ongoing observational search for refractory carbon grain destruction. We also discuss the implications on the overall gas phase chemistry within sublimation zones and on the ultimate composition of planetary bodies forming from available materials.

40

Bailey, Mark E. "Formation of Outer Solar System Bodies: Comets and Planetesimals." Symposium - International Astronomical Union 160 (1994): 443–59. http://dx.doi.org/10.1017/s0074180900046702.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Observations of massive, extended discs around both pre-main-sequence and main-sequence stellar systems indicate that protoplanetary discs larger than the observed planetary system are a common phenomenon, while the existence of large comets suggests that the total cometary mass is much greater than previous estimates. Both observations suggest that theories of the origin of the solar system are best approached from the perspective provided by theories of star formation, in particular that the protoplanetary disc may have extended up to ~103 AU. A model with a surface density distribution similar to a minimum-mass solar nebula, but extending further in radius, is derived by considering the gravitational collapse of a uniform, slowly rotating molecular cloud. The boundary of the planetary system is determined not by lack of mass, as in previous ‘mass-limited’ models (i.e. those with a sharp decrease in surface density Σ beyond the radius of the observed planetary system), but instead by the increasing collision time between the comets or planetesimals initially formed by gravitational instability beyond the planetary zone. Bodies formed beyond ~50 AU have sizes on the order of 102 km and represent a collisionally unevolved population; they are composed of relatively small, unaltered clumps of interstellar dust and ices with individual sizes estimated to range up to ~10 m. By contrast, bodies formed closer in, for example in the Uranus-Neptune zone, consist of larger agglomerations of dust and ices with individual sizes ranging up to ~1 km. Planetesimals formed by gravitational instability at smaller heliocentric distances r are typically much smaller than those formed further out, the masses mp being proportional to Σ3r6, but subsequent collisional aggregation in the planetary region is expected to produce bodies with sizes ranging up to 102 km or more. In both cases the first-formed solid objects may be identified with observed cometary nuclei; some accumulate to produce the outer planets, but the majority are ejected, either to interstellar space or into the Oort cloud. Observed comets represent a dynamically well-mixed group from various sources; they are expected to comprise a heterogeneous mix of both pristine and relatively altered material and to have a broad mass distribution ranging up to the size of the largest planetesimals.

41

Richter, Robert, and Filip Maric. "Ecological Bodies and Relational Anatomies: Toward a Transversal Foundation for Planetary Health Education." Challenges 13, no. 2 (August 9, 2022): 39. http://dx.doi.org/10.3390/challe13020039.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

As planetary health education enters medical and health professional training, transversal implementation across curricula is critical in developing its full potential and enabling future health professionals to meet the social, environmental, and health challenges of current and future generations in an integrated manner. To advance the transversal implementation of planetary health education, our study proceeded through: (1) a sequence analysis of documents framing physiotherapy education to identify relevant nexus points; (2) an explorative implementation of planetary health into foundational anatomy and physiology modules identified as critical nexus points; (3) practical implementation during the 2021 autumn semester. Implementation in the operative foundations of healthcare education—anatomy and physiology—enables the emphasis of the ecological nature of human bodies and interconnection with our planetary environment. Musculoskeletal joints accentuate the relational nature of bodies highlighted across current research and traditional knowledges, as dynamically pervaded and in interaction with culture, technology, objects, ideas, plants, planets, etc. Teaching relational anatomies thus highlights planetary health as the transversal foundation of medical and healthcare education. Making this foundation more explicit will be critical for the transversal implementation of planetary health education and subsequent practice, as well as the fundamental shifts in our understanding of human lives and health they require.

42

Mrozewski, Tomasz. "Planetary GIS and the USGS Astrogeology Science Center." Bulletin - Association of Canadian Map Libraries and Archives (ACMLA), no. 161 (April 1, 2019): 17–20. http://dx.doi.org/10.15353/acmla.n161.725.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

43

Gussie, Grant. "A Speculation into the Origin of Neutral Globules in Planetary Nebulae: Could the Helix’s Comets Really be Comets?" Publications of the Astronomical Society of Australia 12, no. 2 (August 1995): 170–73. http://dx.doi.org/10.1017/s1323358000020221.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractA novel explanation for the origin of the cometary globules within NGC 7293 (the ‘Helix’ planetary nebula) is examined, namely that these globules originate as massive cometary bodies at large astrocentric radii. The masses of such hypothetical cometary bodies would have to be several orders of magnitude larger than those of any such bodies observed in our solar system in order to supply the observed mass of neutral gas. It is, however, shown that comets at ‘outer Oort cloud’ distances are likely to survive past the red giant and asymptotic giant branch evolutionary phases of the central star, allowing them to survive until the formation of the planetary nebula. Some observational tests of this hypothesis are proposed.

44

Sicardy, Bruno. "Small Bodies Around Other Stars." Symposium - International Astronomical Union 160 (1994): 429–42. http://dx.doi.org/10.1017/s0074180900046696.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

We briefly review recent advances in the observation and study of planetary bodies in extra-solar systems. We summarize in particular the main physical properties of the β-Pictoris dust disk, and the status of new disk observations. Theoretical implications of infalling discrete bodies are considered, in particular, the existence of possible perturbing planet(s) causing this influx. Such planets could spectacularly disturb circumstellar dust disks, thus revealing themselves in spite of their intrinsic faintness as mere point sources. Finally, we describe the recent possible discovery of at least two planets around a pulsar. This underlines the potential existence of planets in rather exotic circumstances.

45

Ji, Jianghui, L. Liu, and G. Y. Li. "On secular resonances of small bodies in the planetary systems." Proceedings of the International Astronomical Union 2, S236 (August 2006): 77–84. http://dx.doi.org/10.1017/s1743921307003092.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

AbstractWe investigate the secular resonances for massless small bodies and Earth-like planets in several planetary systems. We further compare the results with those of Solar System. For example, in the GJ 876 planetary system, we show that the secular resonances ν1 and ν2 (respectively, resulting from the inner and outer giant planets) can excite the eccentricities of the Earth-like planets with orbits 0.21≤ a <0.50 AU and eject them out of the system in a short timescale. However, in a dynamical sense, the potential zones for the existence of Earth-like planets are in the area 0.50≤ a ≤1.00 AU, and there exist all stable orbits last up to 105 yr with low eccentricities. For other systems, e.g., 47 UMa, we also show that the Habitable Zones for Earth-like planets are related to both secular resonances and mean motion resonances in the systems.

46

Aliev, F. R., A. V. Lazurkevich, and I.-Kan An. "Planetary Gear on Basis of Diplane Meshing with Intermediate Bodies." Intellekt. Sist. Proizv. 15, no. 1 (March 15, 2017): 4. http://dx.doi.org/10.22213/2410-9304-2017-1-4-8.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Рассмотрена конструкция и предложена методика геометрического расчета и кинематического анализа одной из разновидностей планетарных передач с зацеплением промежуточных тел-шариков с улучшенными характеристиками [1]: высоким КПД за счет уменьшения потерь на трение, увеличенной нагрузочной способностью за счет многопарности зацепления, компактностью и т. д. Планетарная передача содержит два солнечных колеса, водило, сателлит и две группы промежуточных тел-шариков, контактирующихся с поверхностями зубьев, выполненных на обращенных друг к другу торцевых поверхностях солнечных колес и сателлита. При этом каждая группа промежуточных тел-шариков отдельно позиционируются и объединяются с помощью сепаратора, представляющего диск с отверстиями для шариков. Для исключения нагрузки на сепараторе оси зацепления в каждой паре зацеплений, составленной солнечным колесом, сателлитом и сепаратором с промежуточными телами-шариками, совмещены. Приведен численный пример геометрического и кинематического расчетов передачи. Показано, что соответствующим подбором параметров можно свести скорость скольжения шариков относительно поверхностей зубьев близкой к нулю.

47

Yoshimitsu, Tetsuo, Takashi Kubota, and Ichiro Nakatani. "New Mobility System of Exploration Rover for Small Planetary Bodies." Journal of the Robotics Society of Japan 18, no. 2 (2000): 292–99. http://dx.doi.org/10.7210/jrsj.18.292.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

48

Kerr, R. A. "LUNAR AND PLANETARY SCIENCE CONFERENCE: Cold, Cold Bodies, Warm Hearts." Science 315, no. 5820 (March 30, 2007): 1789a. http://dx.doi.org/10.1126/science.315.5820.1789a.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

49

Wilkman, Olli, Karri Muinonen, and Jouni Peltoniemi. "Photometry of dark atmosphereless planetary bodies: an efficient numerical model." Planetary and Space Science 118 (December 2015): 250–55. http://dx.doi.org/10.1016/j.pss.2015.06.004.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

50

Price, P. Buford. "Life in Solid Ice on Earth and Other Planetary Bodies." Symposium - International Astronomical Union 213 (2004): 363–66. http://dx.doi.org/10.1017/s0074180900193556.

Повний текст джерела

Стилі APA, Harvard, Vancouver, ISO та ін.

Анотація:

Theory and direct observation indicate that micro-organisms exist in liquid veins in ice and permafrost, provided the temperature is above the eutectic for H2O and soluble impurities present. Microbes can exist and metabolize in glacial ice and permafrost on Earth, Mars, and Europa. One can search directly (with fluorescence microscopy at liquid veins in Vostok ice core samples) or with a biologging instrument (for microbial fluorescence in a borehole in terrestrial or martian permafrost or ice). The viability lifetime against DNA destruction of bacterial spores can be measured with analytical techniques that identify calcium dipicolinate, which is unique to spores.