Journal articles: 'Lunar variations'

1

Winch, Denis E. "Lunar magnetic variations." Pure and Applied Geophysics PAGEOPH 131, no. 3 (1989): 533–49. http://dx.doi.org/10.1007/bf00876844.

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2

Palumbo, A. "Lunar daily variations in rainfall." Journal of Atmospheric and Terrestrial Physics 48, no. 2 (February 1986): 145–48. http://dx.doi.org/10.1016/0021-9169(86)90078-4.

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3

Winch, D. E. "Solar and Lunar Daily Geomagnetic Variations." Exploration Geophysics 24, no. 2 (June 1993): 147–50. http://dx.doi.org/10.1071/eg993147.

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4

Edwards, B. C., J. J. Bloch, D. Roussel-Dupré, T. E. Pfafman, and Sean Ryan. "ALEXIS Lunar Observations." International Astronomical Union Colloquium 152 (1996): 465–70. http://dx.doi.org/10.1017/s0252921100036393.

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The ALEXIS small satellite was designed as a large area monitor operating at extreme ultraviolet wavelengths (130 − 190 Å). At these energies, the moon is the brightest object in the night sky and was the first source identified in the ALEXIS data. Due to the design of ALEXIS and the lunar orbit, the moon is observed for two weeks of every month. Since lunar emissions in the extreme ultraviolet are primarily reflected solar radiation these observations may be useful as a solar monitor in the extreme ultraviolet. The data show distinct temporal and spectral variations indicating similar changes in the solar spectrum. We will present a preliminary dataset of lunar observations and discussions covering the variations observed and how they relate to the solar spectrum.

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Zaman, Fahad, Lawrence W. Townsend, Wouter C. de Wet, Harlan E. Spence, Jody K. Wilson, Nathan A. Schwadron, Andrew P. Jordan, and Sonya S. Smith. "Composition variations of major lunar elements: Possible impacts on lunar albedo spectra." Icarus 369 (November 2021): 114629. http://dx.doi.org/10.1016/j.icarus.2021.114629.

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TRIVEDI, NB, and RG RASTOGI. "Lunar tidal oscillations in horizontal magnetic intensity at Kodaikanal during periods of low and high sunspots." MAUSAM 20, no. 3 (April 30, 2022): 235–46. http://dx.doi.org/10.54302/mausam.v20i3.5452.

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The paper describes the lunar daily (L) variations at fixed lunar ages and the lunar monthly (M) variations at fixed solar hours in horizontal magnetic intensity (.H) at Kodaikanal for the low sunspot period, Jan, 1951 to Dec, 1955; and for the high sunspot period Jan. 1956 to Dec, 1960. The lunar daily variations at any of the seasons or solar activity epochs are found to follow Chapman's phase law: L=Cn sin [n~+(.n-2)v+an]. With the increase of solar activity the phase of Ls wave remains constant for each of the seasons, but the amplitude increases during D. and E. months and slightly decreases during the months, The lunar semi monthly (.M2) waves at fixed solar hours vary with the solar time in the same way as the electrojet current, i.e., the amplitude starts increasing with sunrise reaches a maximum near noon and decreases to a low value by sunset. The ratio of lunar semidiurnal (LB} wave to the solar semidiurnal (82) wave for any of the seasons decreases with solar activity. The amplitudes of LB or M2 wave at Kodaikanal are much smaller than the corresponding values at Huancayo indicating the longitudinal variation in the lunar daytime effects in H along the magnetic equator. The lunar semimonthly tides for the daytime hours are predominantly under the control of lunar time during the D. months and of lunar age during the J .months.

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Pearce, Steven J., and H. J. Melosh. "Terrace width variations in complex lunar craters." Geophysical Research Letters 13, no. 13 (December 1986): 1419–22. http://dx.doi.org/10.1029/gl013i013p01419.

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8

McKnight, J. D. "Lunar daily geomagnetic variations in New Zealand." Geophysical Journal International 122, no. 3 (December 1995): 889–98. http://dx.doi.org/10.1111/j.1365-246x.1995.tb06844.x.

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9

Antonov, Yu V. "ABOUT A POSSIBLE CONNECTION BETWEEN EARTHQUAKES AND LUNAR-SOLAR GRAVITY VARIATIONS." Proceedings of higher educational establishments. Geology and Exploration, no. 3 (June 25, 2018): 51–57. http://dx.doi.org/10.32454/0016-7762-2018-3-51-57.

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A possible correlation between the destructive earthquakes of magnitude M = 7 and above and luni-solar gravity variations between 1975 and 2015 has been analyzed. The lunar-solar variations are characterized by three extreme points: the maximum and minimum values of gravity, and the maximum rate of change of variations. At this time, there is an extreme impact of lunar-solar attraction on the earth’s crust and the Earth as a whole. Variations can be a source of irreversible deformation in the earth’s crust. If in this case, there is an additional external impact of space factors, the probability of an earthquake is increased. In a time, the earthquakes are grouped near extremes of lunar-solar variations: half of the events are associated with the maximum gradient of variations change, and the second half is equally confined to the maximum and minimum value of gravity variations. Lunar-solar variations of gravity in conjunction with other cosmic influences can cause earthquakes.

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McGee, J. J. "Lunar ferroan anorthosites: Mineralogy, compositional variations, and petrogenesis." Journal of Geophysical Research: Planets 98, E5 (May 25, 1993): 9089–105. http://dx.doi.org/10.1029/93je00400.

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11

Stening, R. J. "What do lunar geomagnetic variations tell us about the lunar tide in the lower thermosphere?" Advances in Space Research 12, no. 6 (1992): 267–70. http://dx.doi.org/10.1016/0273-1177(92)90070-e.

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12

Jin, Da Wei, Jian Qiao Li, Shi Chao Fan, Hao Li, and Yang Wang. "Analysis on the Movement Effect of Lunar Rover Wheel." Applied Mechanics and Materials 307 (February 2013): 211–14. http://dx.doi.org/10.4028/www.scientific.net/amm.307.211.

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It is important to analyze mechanical relationship between lunar wheel and lunar soil for studying passing ability of regolith in lunar soil. Mechanical relationship between lunar wheel and regolith could be reflected by these parameters such as sinkage, drawbar pull, driving torque, motion resistance and slip when the lunar wheel moves. Thus, it is necessary to analyze these parameters of lunar wheel by soil bin test. The test results show that, the four parameters increase with slip and loading, except motion resistance of the test wheel which is under 70N at the speed of 25mm/s. The variations of the four parameters are not significantly influenced by velocity. The variations of the four parameters are significantly influenced by loading.

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13

Sedaghatpour, Fatemeh, and Stein B. Jacobsen. "Magnesium stable isotopes support the lunar magma ocean cumulate remelting model for mare basalts." Proceedings of the National Academy of Sciences 116, no. 1 (December 17, 2018): 73–78. http://dx.doi.org/10.1073/pnas.1811377115.

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We report high-precision Mg isotopic analyses of different types of lunar samples including two pristine Mg-suite rocks (72415 and 76535), basalts, anorthosites, breccias, mineral separates, and lunar meteorites. The Mg isotopic composition of the dunite 72415 (δ25Mg = −0.140 ± 0.010‰, δ26Mg = −0.291 ± 0.018‰), the most Mg-rich and possibly the oldest lunar sample, may provide the best estimate of the Mg isotopic composition of the bulk silicate Moon (BSM). This δ26Mg value of the Moon is similar to those of the Earth and chondrites and reflects both the relative homogeneity of Mg isotopes in the solar system and the lack of Mg isotope fractionation by the Moon-forming giant impact. In contrast to the behavior of Mg isotopes in terrestrial basalts and mantle rocks, Mg isotopic data on lunar samples show isotopic variations among the basalts and pristine anorthositic rocks reflecting isotopic fractionation during the early lunar magma ocean (LMO) differentiation. Calculated evolutions of δ26Mg values during the LMO differentiation are consistent with the observed δ26Mg variations in lunar samples, implying that Mg isotope variations in lunar basalts are consistent with their origin by remelting of distinct LMO cumulates.

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14

Starjinsky, S. S. "Studying the dynamics of the lunar daily geomagnetic variations." Geomagnetism and Aeronomy 48, no. 2 (April 2008): 265–76. http://dx.doi.org/10.1134/s0016793208020175.

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15

Venkatadri, T. K., and P. B. James. "Variations of porosity in intermediate-sized lunar impact basins." Icarus 352 (December 2020): 113953. http://dx.doi.org/10.1016/j.icarus.2020.113953.

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16

Cloutis, Edward A., and Michael J. Gaffey. "Lunar Regolith Analogues: Spectral Reflectance Properties of Compositional Variations." Icarus 102, no. 2 (April 1993): 203–24. http://dx.doi.org/10.1006/icar.1993.1044.

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17

Jawin, Erica R., Sebastien Besse, Lisa R. Gaddis, Jessica M. Sunshine, James W. Head, and Sara Mazrouei. "Examining spectral variations in localized lunar dark mantle deposits." Journal of Geophysical Research: Planets 120, no. 7 (July 2015): 1310–31. http://dx.doi.org/10.1002/2014je004759.

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18

Arora, B. R., D. R. K. Rao, and N. S. Sastri. "Geomagnetic solar and lunar daily variations at Alibag, India." Pure and Applied Geophysics PAGEOPH 122, no. 1 (1985): 89–109. http://dx.doi.org/10.1007/bf00879651.

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19

Zhong, Zhen, Jianguo Yan, and Zhiyong Xiao. "Lunar Regolith Temperature Variation in the Rümker Region Based on the Real-Time Illumination." Remote Sensing 12, no. 4 (February 22, 2020): 731. http://dx.doi.org/10.3390/rs12040731.

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Chang’E-5 will be China’s first sample−return mission. The proposed landing site is at the late-Eratosthenian-aged Rümker region of the lunar nearside. During this mission, a driller will be sunk into the lunar regolith to collect samples from depths up to two meters. This mission provides an ideal opportunity to investigate the lunar regolith temperature variation, which is important to the drilling program. This study focuses on the temperature variation of lunar regolith, especially the subsurface temperature. Such temperature information is crucial to both the engineering needs of the drilling program and interpretation of future heat-flow measurements at the lunar landing site. Based on the real-time illumination, and particularly the terrain obscuration, a one-dimensional heat equation was applied to estimate the temperature variation over the whole landing region. Our results confirm that while solar illumination strongly affects the surface temperature, such effect becomes weak at increasing depths. The skin depth of diurnal temperature variations is restricted to the uppermost ~5 cm, and the temperature of regolith deeper than ~0.6 m is controlled by the interior heat flow. At such a depth, China’s future lunar exploration is adequate to measure the inner heat flow, considering the drilling depth will be close to 2 m.

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20

Stening, R. J., and C. Jacobi. "Lunar tidal winds in the upper atmosphere over Collm." Annales Geophysicae 18, no. 12 (December 31, 2000): 1645–50. http://dx.doi.org/10.1007/s00585-001-1645-6.

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Abstract. The lunar semidiurnal tide in winds measured at around 90 km altitude has been isolated with amplitudes observed up to 4 m s–1. There is a marked amplitude maximum in October and also a considerable phase variation with season. The average variation of phase with height indicated a vertical wavelength of more than 80 km but this, and other results, needs to be viewed in the light of the considerable averaging required to obtain statistical significance. Large year-to-year variations in both amplitude and phase were also found. Some phase comparisons with the GSWM model gave reasonable agreement but the model amplitudes above a height of 100 km were much larger than those measured. An attempt to make a comparison with the lunar geomagnetic tide did not yield a statistically significant result. Key words: Meteorology and atmospheric dynamics (middle atmosphere dynamics; waves and tides)

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21

Barkin, M. Yu, P. M. Shkapov, and Hideo Hanada. "The Physical Librations of the Moon Caused by its Tidal Deformation." Herald of the Bauman Moscow State Technical University. Series Natural Sciences, no. 83 (2018): 4–16. http://dx.doi.org/10.18698/1812-3368-2019-2-4-16.

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The Moon, like Earth, is not completely solid, and experiences deformation changes, for example due to the tides, caused by the gravitational pull of the Earth's orbit in a complex and resonant nature of the motion of the Moon. It is shown that these deformations lead to temporary variations of Moon inertia tensor components and consequently to the variations in the movement of the poles of the Moon, as well as to the variations of axial rotation. The indicated variations module is in the order of 10--12 mas (millisecond of arc). There variations are important for the development of the high-precision theory of lunar physical libration, suitable for modern projects for the reclamation of the Moon, in particular the Japanese project ILOM, which contemplates installing the telescope on the lunar surface and determining its orientation accuracy of the order of 1--0.1 msd, as well as the Russian lunar program, providing the launch of five automatic stations to the Moon in 2019--2024

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22

Fiedler, Jens, and Gerd Baumgarten. "Solar and lunar tides in noctilucent clouds as determined by ground-based lidar." Atmospheric Chemistry and Physics 18, no. 21 (November 8, 2018): 16051–61. http://dx.doi.org/10.5194/acp-18-16051-2018.

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Abstract. Noctilucent clouds (NLCs) occur during summer from midlatitudes to high latitudes. They consist of nanometer-sized ice particles in an altitude range from 80 to 90 km and are sensitive to ambient temperature and water vapor content, which makes them a suitable tracer for variability on all timescales. The data set acquired by the ALOMAR Rayleigh–Mie–Raman (RMR) lidar covers 21 years and is investigated regarding tidal signatures in NLCs. For the first time solar and lunar tidal parameters in NLCs were determined simultaneously from the same data. Several NLC parameters are subject to persistent mean variations throughout the solar day as well as the lunar day. Variations with lunar time are generally smaller compared to variations with solar time. NLC occurrence frequency shows the most robust imprint of the lunar semidiurnal tide. Its amplitude is about 50 % of the solar semidiurnal tide, which is surprisingly large. Phase progressions of NLC occurrence frequency indicate upward propagating solar tides. Below 84 km altitude the corresponding vertical wavelengths are between 20 and 30 km. For the lunar semidiurnal tide phase progressions vary symmetrically with respect to the maximum of the NLC layer.

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23

Kravchenko, Yu A. "The lunar influence on the vertical deflections and gravity variations." Geodesy and Cartography 928, no. 10 (November 20, 2017): 2–9. http://dx.doi.org/10.22389/0016-7126-2017-928-10-2-9.

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The increase of building complexity causes the raise of requirements for accuracy of geodetic observations and the necessity to revise the variety of factors influencing the measurement results. Such factors include the lunar influence on the gravity intensity and direction. The necessity of correcting geodetic observations by the lunar influence and estimation of their highest influence on the Earth gravity and vertical deflections are outlined. The results obtained from the computational experiment on extreme values estimation of vertical deflections (up to 1''), variations of measured heights (up to 0,5 mm by 100 m) and gravity variations (up to 5,44 × 10^(-5) m∙kg / с^2) are sufficient to modify the existing techniques for precision leveling and gravity observations. Another argument in favor of the need to take into account the Moon influence and other factors is the accuracy increase of geodetic instruments (levels and gravimeters).Without changing the method of performing high-precision leveling and gravity measurements and entering the necessary corrections, real accuracy increase of these works can not be achieved. In this case, the ideas about the accuracy achieved, for example, when it is estimated by internal convergence, will be overestimated.

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24

Müller, Jürgen, and Liliane Biskupek. "Variations of the gravitational constant from lunar laser ranging data." Classical and Quantum Gravity 24, no. 17 (August 21, 2007): 4533–38. http://dx.doi.org/10.1088/0264-9381/24/17/017.

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25

Stening, R. J., and R. G. Rastogi. "Variations of the lunar geomagnetic tide in the Indian region." Journal of Atmospheric and Solar-Terrestrial Physics 64, no. 4 (March 2002): 471–77. http://dx.doi.org/10.1016/s1364-6826(02)00075-5.

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26

Greber, Nicolas D., Nicolas Dauphas, Igor S. Puchtel, Beda A. Hofmann, and Nicholas T. Arndt. "Titanium stable isotopic variations in chondrites, achondrites and lunar rocks." Geochimica et Cosmochimica Acta 213 (September 2017): 534–52. http://dx.doi.org/10.1016/j.gca.2017.06.033.

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27

López, Ericson, Franklin Aldás, and Akimasa Yoshikawa. "Analysis of Magnetic Field Variations Produced by Equatorial Electro-Jets." Proceedings of the International Astronomical Union 13, S335 (July 2017): 125–27. http://dx.doi.org/10.1017/s1743921318000662.

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AbstractThe Equatorial Electrojet (EEJ) is a narrow band of electrons flowing from east to west at daytime at low latitudes. The electron current produces a magnetic field variation that can be measured at different latitudes. In this work, we have used the data analysis in order to quantify the solar and lunar contributions to those variations and study the morphology of the EEJ current.

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28

Hapgood, M. "Modelling long-term trends in lunar exposure to the Earth's plasmasheet." Annales Geophysicae 25, no. 9 (October 2, 2007): 2037–44. http://dx.doi.org/10.5194/angeo-25-2037-2007.

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Abstract. This paper shows how the exposure of the Moon to the Earth's plasmasheet is subject to decadal variations due to lunar precession. The latter is a key property of the Moon's apparent orbit around the Earth – the nodes of that orbit precess around the ecliptic, completing one revolution every 18.6 years. This precession is responsible for a number of astronomical phenomena, e.g. the year to year drift of solar and lunar eclipse periods. It also controls the ecliptic latitude at which the Moon crosses the magnetotail and thus the number and duration of lunar encounters with the plasmasheet. This paper presents a detailed model of those encounters and applies it to the period 1960 to 2030. This shows that the total lunar exposure to the plasmasheet will vary from 10 h per month at a minimum of the eighteen-year cycle rising to 40 h per month at the maximum. These variations could have a profound impact on the accumulation of charge due plasmasheet electrons impacting the lunar surface. Thus we should expect the level of lunar surface charging to vary over the eighteen-year cycle. The literature contains reports that support this: several observations made during the cycle maximum of 1994–2000 are attributed to bombardment and charging of the lunar surface by plasmasheet electrons. Thus we conclude that lunar surface charging will vary markedly over an eighteen-year cycle driven by lunar precession. It is important to interpret lunar environment measurements in the context of this cycle and to allow for the cycle when designing equipment for deployment on the lunar surface. This is particularly important in respect of developing plans for robotic exploration on the lunar surface during the next cycle maximum of 2012–2019.

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29

Sherstyukov, B. G. "Lunar perturbations in variations of earth angular velocity and atmospheric pressure." Russian Meteorology and Hydrology 37, no. 8 (August 2012): 514–20. http://dx.doi.org/10.3103/s106837391208002x.

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30

Bhuyan, P. K., and T. R. Tyagi. "Lunar and solar daily variations of equivalent slab thickness at Delhi." Geophysical Journal International 88, no. 2 (February 1, 1987): 487–93. http://dx.doi.org/10.1111/j.1365-246x.1987.tb06655.x.

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31

De Meyer, Frans. "A modulation model for the solar and lunar daily geomagnetic variations." Earth, Planets and Space 55, no. 7 (July 2003): 405–18. http://dx.doi.org/10.1186/bf03351774.

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32

Çelik, Cengiz, Mustafa Kemal Tunçer, Elif Tolak-Çiftçi, Metin Zobu, Naoto Oshiman, and S. Bülent Tank. "Solar and lunar geomagnetic variations in the northwestern part of Turkey." Geophysical Journal International 189, no. 1 (February 20, 2012): 391–99. http://dx.doi.org/10.1111/j.1365-246x.2012.05382.x.

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33

Rastogi, R. G., H. Chandra, and G. Sethia. "Solar and lunar variations in TEC at low latitudes in India." Journal of Atmospheric and Terrestrial Physics 47, no. 4 (April 1985): 309–17. http://dx.doi.org/10.1016/0021-9169(85)90011-x.

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34

Bhuyan, P. K., and T. R. Tyagi. "Lunar and solar daily variations of ionospheric electron content at Delhi." Journal of Atmospheric and Terrestrial Physics 48, no. 3 (March 1986): 301–10. http://dx.doi.org/10.1016/0021-9169(86)90106-6.

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35

Jansen, J. C., J. C. Andrews-Hanna, Y. Li, P. G. Lucey, G. J. Taylor, S. Goossens, F. G. Lemoine, et al. "Small-scale density variations in the lunar crust revealed by GRAIL." Icarus 291 (July 2017): 107–23. http://dx.doi.org/10.1016/j.icarus.2017.03.017.

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McFadden, James, Ian Garrick-Bethell, Chae K. Sim, Sungsoo S. Kim, and Doug Hemingway. "Iron content determines how space weathering flux variations affect lunar soils." Icarus 333 (November 2019): 323–42. http://dx.doi.org/10.1016/j.icarus.2019.05.033.

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37

Yamazaki, Y., and M. J. Kosch. "Geomagnetic lunar and solar daily variations during the last 100 years." Journal of Geophysical Research: Space Physics 119, no. 8 (August 2014): 6732–44. http://dx.doi.org/10.1002/2014ja020203.

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38

Scholz, M. "Stellar radii." Symposium - International Astronomical Union 189 (1997): 51–58. http://dx.doi.org/10.1017/s0074180900116493.

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Observing a stellar radius basically means observing a center-to-limb intensity variation. The significance and properties of center-to-limb variations, common approximations, the correlation with optical-depth radii in extended-photophere stars, and direct measurements of angular (interferometry, lunar occultation) and absolute diameters (binary eclipses) are discussed. Spectrophotometric and doppler techniques of diameter determination are also briefly outlined.

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NORDTVEDT, KENNETH. "SPACE–TIME VARIATION OF PHYSICAL CONSTANTS AND THE EQUIVALENCE PRINCIPLE." International Journal of Modern Physics A 17, no. 20 (August 10, 2002): 2711–15. http://dx.doi.org/10.1142/s0217751x02011655.

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Location-dependence of physical parameters such as the electromagnetic fine structure constant and Newton's G produce body accelerations which violate universality of free fall rates testable with laboratory and space experiments. Theoretically related cosmological time variation of these same parameters are also constrained by experiments such as lunar laser ranging, and these time variations produce accelerations of bodies relative to a preferred cosmological inertial frame.

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Fujimoto, Akiko, Akimasa Yoshikawa, Teiji Uozumi, and Shuji Abe. "Seasonal dependence of semidiurnal equatorial magnetic variation during quiet and disturbed periods." E3S Web of Conferences 127 (2019): 02025. http://dx.doi.org/10.1051/e3sconf/201912702025.

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The analysis of 20-year long-term semidiurnal lunar tidal variations gave the evidence that the semidiurnal variations are completely different between the magnetic quiet and disturbed periods. This is the first time that the seasonal dependence of disturbance-time semidiurnal variation has been provided from the analysis of the EE-index. We found the Kp dependence of semidiurnal variation: For full and new moon phase, counter troughs are amplified during disturbance time, possibly related to disturbance dynamo. For all moon phase, there are positive enhancements in dawn and strong depressions after sunset, resulting from the penetration of polar electric filed. For Seasonal dependence, semidiurnal variations are divided to three seasonal groups, and characterized as deep trough, enhanced crest and weak structure for D-solstice, Equinoxes and J-solstice, respectively. There is no significant longitudinal difference between Ancon and Davao, except for the amplitude of semidiurnal variations. The deep troughs occur during D-solstice and the enhanced crests during Equinoxes, at both Ancon and Davao.

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41

Ferrándiz, J. M., Yu V. Barkin, and J. Getino. "Tidal Variations of the Earth Rotation." International Astronomical Union Colloquium 178 (2000): 565–69. http://dx.doi.org/10.1017/s025292110006173x.

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AbstractThe equations for the rotation of a weakly deformable celestial body in non canonical Andoyer variables have been used to study the perturbation of Earth rotation due to tidal deformation raised by the Moon and Sun. A theory of the perturbed rotational motion of an isolated weakly deformable body in Andoyer variables and in components of the angular velocity has been developed. Mantle tidal deformations due to lunar and solar influences were analytically described and taken into account. Perturbations of the first order in the Earth’s polar motion were determined.

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Dawkins, E. C. M., M. Sarantos, D. Janches, E. Mierkiewicz, and A. Colaprete. "Selenographic and Local Time Dependence of Lunar Exospheric Sodium as Observed by LADEE." Planetary Science Journal 3, no. 9 (September 1, 2022): 220. http://dx.doi.org/10.3847/psj/ac8805.

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Abstract Even though sodium (Na) has been known to be a constituent of the lunar exosphere for the past thirty years, limitations introduced by Earth-based observations make it difficult to determine how its distribution varies with local time. We used observations from the Ultraviolet and Visible Spectrometer instrument on board the NASA Lunar Atmosphere and Dust Environment Explorer mission to search for evidence of near-instantaneous dayside variation of exospheric Na across one lunation (2014 February–March). Through comparison with model simulations, the data appear to be consistent with persistent southern enhancements of Na, while no evidence of systematic depletion of the Na exosphere reservoir within two hours of local noon was obtained. The results indicate an enhancement of the gas density over Mare regions and the lunar nearside; though this finding could mean that the weak Na emission is lost in the scattering continuum over brighter soils. Day-to-day variability is observed and may reflect a changing solar wind and meteoroid environment combined with inhomogeneities in the gas–surface interaction parameters and Na distribution on the lunar surface. We found that, due to the limited viewing geometry and sensitivity of the instrument to scattering from the bright lunar surface, it is difficult to uniquely separate the latitudinal and local time variations of Na.

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43

Huang, Yinn-Nien. "Solar and Lunar Daily Geomagnetic Variations at Lunping from 1966 to 1989." Terrestrial, Atmospheric and Oceanic Sciences 1, no. 3 (1990): 243. http://dx.doi.org/10.3319/tao.1990.1.3.243(a).

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Baumann-Pickering, Simone, Ana Širović, Marie A. Roch, Anne E. Simonis, Sean M. Wiggins, Erin M. Oleson, and John A. Hildebrand. "Diel and lunar variations of marine ambient sound in the North Pacific." Journal of the Acoustical Society of America 130, no. 4 (October 2011): 2536. http://dx.doi.org/10.1121/1.3655131.

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45

Miljkovic, K., M. A. Wieczorek, G. S. Collins, M. Laneuville, G. A. Neumann, H. J. Melosh, S. C. Solomon, R. J. Phillips, D. E. Smith, and M. T. Zuber. "Asymmetric Distribution of Lunar Impact Basins Caused by Variations in Target Properties." Science 342, no. 6159 (November 7, 2013): 724–26. http://dx.doi.org/10.1126/science.1243224.

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Rosser, W. G. V., and D. M. Schlapp. "Geomagnetic lunar variations due to the ocean dynamo measured at European observatories." Geophysical Journal International 103, no. 1 (October 1990): 257–60. http://dx.doi.org/10.1111/j.1365-246x.1990.tb01767.x.

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Anufriev, G. S. "Long-term variations of solar corpuscular fluxes based on lunar soil samples." Astrophysical Bulletin 68, no. 3 (July 2013): 352–57. http://dx.doi.org/10.1134/s1990341313030097.

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CHENET, H., P. LOGNONNE, M. WIECZOREK, and H. MIZUTANI. "Lateral variations of lunar crustal thickness from the Apollo seismic data set." Earth and Planetary Science Letters 243, no. 1-2 (March 15, 2006): 1–14. http://dx.doi.org/10.1016/j.epsl.2005.12.017.

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Hofmeister, Anne M., Robert E. Criss, and Everett M. Criss. "Theoretical and Observational Constraints on Lunar Orbital Evolution in the Three-Body Earth-Moon-Sun System." Astronomy 1, no. 2 (July 11, 2022): 58–84. http://dx.doi.org/10.3390/astronomy1020007.

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Abstract:

Extremely slow recession of the Moon from the Earth has been recently proposed and attributed to conversion of Earth’s axial spin to lunar orbital momentum. This hypothesis is inconsistent with long-standing recognition that the Moon’s orbit involves three-body interactions. This and other short-comings, such as Earth’s spin loss being internal, are summarized here. Considering point-masses is justified by theory and observational data on other moons. We deduce that torque in the Earth-Moon-Sun system increases eccentricity of the lunar orbit but decreases its inclination over time. Consequently, the average lunar orbital radius is decreasing. We also show that lunar drift is too small to be constrained through lunar laser ranging measurements, mainly because atmospheric refraction corrections are comparatively large and variations in lunar cycles are under-sampled. Our findings support co-accretion and explain how orbits evolve in many-body point-mass systems.

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Eade, J. C. "Southeast Asian Intercalation: Variations and Complexities." Journal of Southeast Asian Studies 24, no. 2 (September 1993): 239–50. http://dx.doi.org/10.1017/s0022463400002617.

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Abstract:

One of the constant problems for historians of Southeast Asia is to assimilate its system of adding extra days and extra years to the lunar calendar to make it keep pace with the solar calendar. It is well known that the addition of an extra month should take place 7 times in every 19 years (adhikames), and that the addition of an extra day should occur 11 times in every 57 years (adhikawan). It is also known that the extra month is called second Ashadha and that in Thailand and Cambodia the extra day is given to the previous month, Jyestha.

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Journal articles on the topic 'Lunar variations'

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