Journal articles: 'Venus (Planet)'

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Johnson, Natasha. "The Planet Venus." Eos, Transactions American Geophysical Union 80, no. 22 (June 1, 1999): 248. http://dx.doi.org/10.1029/99eo00187.

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Spohn, Tilman. "The Planet Venus." Planetary and Space Science 48, no. 4 (April 2000): 357–58. http://dx.doi.org/10.1016/s0032-0633(00)00004-0.

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Vidaurri, Monica R., Sandra T. Bastelberger, Eric T. Wolf, Shawn Domagal-Goldman, and Ravi Kumar Kopparapu. "The Outer Edge of the Venus Zone around Main-sequence Stars." Planetary Science Journal 3, no. 6 (June 1, 2022): 137. http://dx.doi.org/10.3847/psj/ac68e2.

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Abstract A key item of interest for planetary scientists and astronomers is the habitable zone: the distance from a host star where a terrestrial planet can maintain necessary temperatures in order to retain liquid water on its surface. However, when observing a system’s habitable zone, it is possible that one may instead observe a Venus-like planet. We define “Venus-like” as greenhouse-gas-dominated atmosphere occurring when incoming solar radiation exceeds infrared radiation emitted from the planet at the top of the atmosphere, resulting in a runaway greenhouse. Our definition of Venus-like includes both incipient and post-runaway greenhouse states. Both the possibility of observing a Venus-like world and the possibility that Venus could represent an end state of evolution for habitable worlds require an improved understanding of the Venus-like planet, specifically the distances where these planets can exist. Understanding this helps us define a “Venus zone”—the region in which Venus-like planets could exist—and assess the overlap with the aforementioned “habitable zone.” In this study, we use a 1D radiative−convective climate model to determine the outer edge of the Venus zone for F0V, G2V, K5V, and M3V and M5V stellar spectral types. Our results show that the outer edge of the Venus zone resides at 3.01, 1.36, 0.68, 0.23, and 0.1 au, respectively. These correspond to incident stellar fluxes of 0.8, 0.55, 0.38, 0.32, and 0.3 S ⊙, respectively, where stellar flux is relative to Earth (1.0). These results indicate that there may be considerable overlap between the habitable zone and the Venus zone.

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Siti Anisa Hidayati, Siti Anisa Hidayati, and Yushardi. "Kajian Penentuan Arah Kiblat Menggunakan Arah Planet Venus." AL - AFAQ : Jurnal Ilmu Falak dan Astronomi 5, no. 1 (June 25, 2023): 120–28. http://dx.doi.org/10.20414/afaq.v5i1.6338.

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The purpose of this research is to find out how to determine the Qibla direction of aplace using the position of the planet Venus and how to prove the calculation of the position ofVenus in the sky. This research is motivated by the question of how to determine the Qibladirection at night if the conditions do not have sophisticated technological equipment. Thisresearch is a descriptive analysis research where all the data is collected through observationtechniques. The research results show that the position of the planet Venus can be used as analternative reference to determine the Qibla direction. Based on observations using astronomicalcalculations, it is known that Venus looks very luminous on the western horizon when the sky isclear and the sun has set perfectly. We can also see one of the planets Venus at dawn on theeastern horizon, so Venus is also often referred to as the morning star. Data on the position of theplanet Venus such as the altitude and azimuth of the planet Venus somewhere are then calculatedusing the horizon coordinate system. The data is used as a theodolite reference. Furthermore, toobtain the actual Qibla direction, the theodolite lens is directed to the position of the planet Venusand rotated clockwise (same as the difference in the azimuth angle with the Qibla azimuth ofVenus). Thus, the position of the planet Venus can be used as an alternative to determine the Qibladirection.

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Lykawka, Patryk Sofia. "Can narrow discs in the inner Solar system explain the four terrestrial planets?" Monthly Notices of the Royal Astronomical Society 496, no. 3 (June 9, 2020): 3688–99. http://dx.doi.org/10.1093/mnras/staa1625.

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ABSTRACT A successful Solar system model must reproduce the four terrestrial planets. Here, we focus on (1) the likelihood of forming Mercury and the four terrestrial planets in the same system (a 4-P system); (2) the orbital properties and masses of each terrestrial planet; and (3) the timing of Earth’s last giant impact and the mass accreted by our planet thereafter. Addressing these constraints, we performed 450 N-body simulations of terrestrial planet formation based on narrow protoplanetary discs with mass confined to 0.7–1.0 au. We identified 164 analogue systems, but only 24 systems contained Mercury analogues, and eight systems were 4-P ones. We found that narrow discs containing a small number of embryos with individual masses comparable to that of Mars and the giant planets on their current orbits yielded the best prospects for satisfying those constraints. However, serious shortcomings remain. The formation of Mercury analogues and 4-P systems was too inefficient (5 per cent and 2 per cent, respectively), and most Venus-to-Earth analogue mass ratios were incorrect. Mercury and Venus analogues also formed too close to each other (∼0.15–0.21 au) compared to reality (0.34 au). Similarly, the mutual distances between the Venus and Earth analogues were greater than those observed (0.34 versus 0.28 au). Furthermore, the Venus–Earth pair was not reproduced in orbital-mass space statistically. Overall, our results suggest serious problems with using narrow discs to explain the inner Solar system. In particular, the formation of Mercury remains an outstanding problem for terrestrial planet formation models.

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Kaltenegger, L., R. C. Payne, Z. Lin, J. Kasting, and L. Delrez. "Hot Earth or Young Venus? A nearby transiting rocky planet mystery." Monthly Notices of the Royal Astronomical Society: Letters 524, no. 1 (June 13, 2023): L10—L14. http://dx.doi.org/10.1093/mnrasl/slad064.

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ABSTRACT Venus and Earth provide astonishingly different views of the evolution of a rocky planet, raising the question of why these two rocky worlds evolved so differently. The recently discovered transiting Super-Earth LP 890-9c (TOI-4306c, SPECULOOS-2c) is a key to the question. It circles a nearby M6V star in 8.46 d. LP890-9c receives similar flux as modern Earth, which puts it very close to the inner edge of the Habitable Zone (HZ), where models differ strongly in their prediction of how long rocky planets can hold onto their water. We model the atmosphere of a hot LP890-9c at the inner edge of the HZ, where the planet could sustain several very different environments. The resulting transmission spectra differ considerably between a hot, wet exo-Earth, a steamy planet caught in a runaway greenhouse, and an exo-Venus. Distinguishing these scenarios from the planet’s spectra will provide critical new insights into the evolution of hot terrestrial planets into exo-Venus. Our model and spectra are available online as a tool to plan observations. They show that observing LP890-9c can provide key insights into the evolution of a rocky planet at the inner edge of the HZ as well as the long-term future of Earth.

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Widodo, Nanang. "Aplikasi Dua Segitiga Sebangun pada Studi Venus Transit di Matahari Tanggal 8 Juni 2004 dari BPD LAPAN Watukosek." CAUCHY 3, no. 1 (November 10, 2013): 38. http://dx.doi.org/10.18860/ca.v3i1.2570.

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Transit planet Venus di cakram matahari (jari-jari = 696000 km) merupakan peristiwa alam yang dapat dilihat secara berkala. Planet Venus merupakan planet kedua dalam sistem tata surya yang mempunyai orbit lebih dekat ke matahari (= 0,723 Astronomical Unit) dibanding jarak bumi-matahari (= 149.600.000 km = 1 AU). Sehingga pada suatu waktu tertentu ada peluang berada tepat di depan Bumi, saat menghadap matahari atau dikenal dengan transit Venus. Proses pengamatan fenomena transit Venus di cakram matahari tersebut dapat diimplimentasikan sebagai aplikasi dua segitiga sebangun, Dimana jari-jari planet Venus (jari-jari = 6051,8 km) dinyatakan sebagai tinggi benda dan jari-jari tinggi bayangan Venus sebesar 20880 km (= 3,65 mm pada cakram matahari). Dimana diameter matahari 1.392.000 km (= 240 mm pada lembar sket). Dengan pengukuran jarak tempuh Venus transit 72,4 mm (419 920 km di cakram matahari) terhadap waktu kontak pertama bayangan Venus pada jam 05.28 UT (12.28 WIB) di tepi timur hingga akhir transit pada 17.50 UT (14.50 WIB) diperoleh kecepatan bayangan Venus sebesar 49,286 km/detik

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Auclair-Desrotour, P., J. Laskar, S. Mathis, and A. C. M. Correia. "The rotation of planets hosting atmospheric tides: from Venus to habitable super-Earths." Astronomy & Astrophysics 603 (July 2017): A108. http://dx.doi.org/10.1051/0004-6361/201628701.

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The competition between the torques induced by solid and thermal tides drives the rotational dynamics of Venus-like planets and super-Earths orbiting in the habitable zone of low-mass stars. The resulting torque determines the possible equilibrium states of the planet’s spin. Here we have computed an analytic expression for the total tidal torque exerted on a Venus-like planet. This expression is used to characterize the equilibrium rotation of the body. Close to the star, the solid tide dominates. Far from it, the thermal tide drives the rotational dynamics of the planet. The transition regime corresponds to the habitable zone, where prograde and retrograde equilibrium states appear. We demonstrate the strong impact of the atmospheric properties and of the rheology of the solid part on the rotational dynamics of Venus-like planets, highlighting the key role played by dissipative mechanisms in the stability of equilibrium configurations.

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Clement, Matthew S., Sean N. Raymond, and John E. Chambers. "Mercury as the Relic of Earth and Venus Outward Migration." Astrophysical Journal Letters 923, no. 1 (December 1, 2021): L16. http://dx.doi.org/10.3847/2041-8213/ac3e6d.

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Abstract In spite of substantial advancements in simulating planet formation, the planet Mercury’s diminutive mass and isolated orbit and the absence of planets with shorter orbital periods in the solar system continue to befuddle numerical accretion models. Recent studies have shown that if massive embryos (or even giant planet cores) formed early in the innermost parts of the Sun’s gaseous disk, they would have migrated outward. This migration may have reshaped the surface density profile of terrestrial planet-forming material and generated conditions favorable to the formation of Mercury-like planets. Here we continue to develop this model with an updated suite of numerical simulations. We favor a scenario where Earth’s and Venus’s progenitor nuclei form closer to the Sun and subsequently sculpt the Mercury-forming region by migrating toward their modern orbits. This rapid formation of ∼0.5 M ⊕ cores at ∼0.1–0.5 au is consistent with modern high-resolution simulations of planetesimal accretion. In successful realizations, Earth and Venus accrete mostly dry, enstatite chondrite–like material as they migrate, thus providing a simple explanation for the masses of all four terrestrial planets, the inferred isotopic differences between Earth and Mars, and Mercury’s isolated orbit. Furthermore, our models predict that Venus’s composition should be similar to the Earth’s and possibly derived from a larger fraction of dry material. Conversely, Mercury analogs in our simulations attain a range of final compositions.

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Saraiya, Usha. "Medical Women on Planet Venus." Journal of South Asian Federation of Obstetrics and Gynaecology 13, no. 3 (September 9, 2021): 185–90. http://dx.doi.org/10.5005/jp-journals-10006-1900.

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11

Demangeon, O. D. S., M. R. Zapatero Osorio, Y. Alibert, S. C. C. Barros, V. Adibekyan, H. M. Tabernero, A. Antoniadis-Karnavas, et al. "Warm terrestrial planet with half the mass of Venus transiting a nearby star." Astronomy & Astrophysics 653 (September 2021): A41. http://dx.doi.org/10.1051/0004-6361/202140728.

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In recent years, the advent of a new generation of radial velocity instruments has allowed us to detect planets with increasingly lower mass and to break the one Earth-mass barrier. Here we report a new milestone in this context by announcing the detection of the lowest-mass planet measured so far using radial velocities: L 98-59 b, a rocky planet with half the mass of Venus. It is part of a system composed of three known transiting terrestrial planets (planets b–d). We announce the discovery of a fourth nontransiting planet with a minimum mass of 3.06−0.37+0.33 M⊕ and an orbital period of 12.796−0.019+0.020 days and report indications for the presence of a fifth nontransiting terrestrial planet. With a minimum mass of 2.46−0.82+0.66 M⊕ and an orbital period 23.15−0.17+0.60 days, this planet, if confirmed, would sit in the middle of the habitable zone of the L 98-59 system. L 98-59 is a bright M dwarf located 10.6ṗc away. Positioned at the border of the continuous viewing zone of the James Webb Space Telescope, this system is destined to become a corner stone for comparative exoplanetology of terrestrial planets. The three transiting planets have transmission spectrum metrics ranging from 49 to 255, which undoubtedly makes them prime targets for an atmospheric characterization with the James Webb Space Telescope, the Hubble Space Telescope, Ariel, or ground-based facilities such as NIRPS or ESPRESSO. With an equilibrium temperature ranging from 416 to 627 K, they offer a unique opportunity to study the diversity of warm terrestrial planets without the unknowns associated with different host stars. L 98-59 b and c have densities of 3.6−1.5+1.4 and 4.57−0.85+0.77 g cm−3, respectively, and have very similar bulk compositions with a small iron core that represents only 12 to 14% of the total mass, and a small amount of water. However, with a density of 2.95−0.51+0.79 g cm−3 and despite a similar core mass fraction, up to 30% of the mass of L 98-59 d might be water.

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Showstack, Randy. "Exploring Venus as a Terrestrial Planet." Eos, Transactions American Geophysical Union 89, no. 43 (October 21, 2008): 423–24. http://dx.doi.org/10.1029/2008eo430010.

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Blamont, J., L. Boloh, V. Kerzhanovich, L. Kogan, M. Kurgansky, V. Linkin, L. Matveenko, et al. "Balloons on planet Venus: Final results." Advances in Space Research 13, no. 2 (February 1993): 145–52. http://dx.doi.org/10.1016/0273-1177(93)90289-n.

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Akim, E. L., V. A. Brumberg, M. D. Kislik, Ju F. Koljuka, G. A. Krasinsky, E. V. Pitjeva, V. A. Shishov, V. A. Stepanianz, M. L. Sveshnikov, and V. F. Tikhonov. "A relativistic theory of motion of the inner planets." Symposium - International Astronomical Union 114 (1986): 63–68. http://dx.doi.org/10.1017/s0074180900147990.

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The theory of the motion of Mercury, Venus, Earth and Mars is constructed by numerical integration. The theory takes into account relativistic corrections in the frame of Schwarzschild's space-time metrics. The constants of the theory are determined by discussion of the Soviet and American radar observations of Mercury, Venus and Mars, position astrometric observations of these planets (and the Sun) and observations of the Soviet artificial satellites of Venus. Apart from the planet elements the value AU and corrections to the adopted radii of Mercury, Venus and Mars are determined. Statistics of residuals is given and accuracy of the theory is estimated. The theory presented is an ephemeris base for deep space experiments.

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Bowler, Sue. "Let's visit Venus!" Astronomy & Geophysics 61, no. 6 (December 1, 2020): 6.13–6.15. http://dx.doi.org/10.1093/astrogeo/ataa082.

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Ostberg, Colby, Stephen R. Kane, Zhexing Li, Edward W. Schwieterman, Michelle L. Hill, Kimberly Bott, Paul A. Dalba, Tara Fetherolf, James W. Head, and Cayman T. Unterborn. "The Demographics of Terrestrial Planets in the Venus Zone." Astronomical Journal 165, no. 4 (March 21, 2023): 168. http://dx.doi.org/10.3847/1538-3881/acbfaf.

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Abstract Understanding the physical characteristics of Venus, including its atmosphere, interior, and its evolutionary pathway with respect to Earth, remains a vital component for terrestrial planet evolution models and the emergence and/or decline of planetary habitability. A statistical strategy for evaluating the evolutionary pathways of terrestrial planets lies in the atmospheric characterization of exoplanets, where the sample size provides sufficient means for determining required runaway greenhouse conditions. Observations of potential exo-Venuses can help confirm hypotheses about Venus’s past, as well as the occurrence rate of Venus-like planets in other systems. Additionally, the data from future Venus missions, such as DAVINCI, EnVision, and VERITAS, will provide valuable information regarding Venus, and the study of exo-Venuses will be complimentary to these missions. To facilitate studies of exo-Venus candidates, we provide a catalog of all confirmed terrestrial planets in the Venus zone, including transiting and nontransiting cases, and quantify their potential for follow-up observations. We examine the demographics of the exo-Venus population with relation to stellar and planetary properties, such as the planetary radius gap. We highlight specific high-priority exo-Venus targets for follow-up observations, including TOI-2285 b, LTT 1445 A c, TOI-1266 c, LHS 1140 c, and L98–59 d. We also discuss follow-up observations that may yield further insight into the Venus/Earth divergence in atmospheric properties.

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Makarov, Valeri V., and Alexey Goldin. "Chaotic Capture of a Retrograde Moon by Venus and the Reversal of Its Spin." Universe 10, no. 1 (December 28, 2023): 15. http://dx.doi.org/10.3390/universe10010015.

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Planets are surrounded by fractal surfaces (traditionally called Hill spheres), separating the inner zones of long-term stable orbital motion of their satellites from the outer space where the gravitational pull from the Sun takes over. Through this surface, external minor bodies in trajectories loosely co-orbital to a planet can be stochastically captured by the planet without any assistance from external perturbative forces, and can become moons chaotically orbiting the planet for extended periods of time. Using state-of-the-art orbital integrators, we simulate such capture events for Venus, resulting in long-term attachment phases by reversing the forward integration of a moon initially attached to the planet and escaping it after an extended period of time. Chaotic capture of a retrograde moon from a prograde heliocentric orbit appears to be more probable because the Hill sphere is almost four times larger in area for a retrograde orbit than for a prograde orbit. Simulated capture trajectories include cases with attachment phases up to 860,000 years for prograde moons and up to 370,000 years for retrograde moons. Although the probability of a long-term chaotic capture from a single encounter is generally low, the high density of co-orbital bodies in the primordial protoplanetary disk makes this outcome possible, if not probable. The early Venus was surrounded by a dusty gaseous disk of its own, which, coupled with the tidal dissipation of the kinetic energy in the moon and the planet, could shrink the initial orbit and stabilize the captured body within the Hill surface. The tidal torque from the moon, for which we use the historical name Neith, gradually brakes the prograde rotation of Venus, and then reverses it, while the orbit continues to decay. Neith eventually reaches the Roche radius and disintegrates, probably depositing most of its material on Venus’ surface. Our calculations show that surface density values of about 0.06 kg m−2 for the debris disk may be sufficient to stabilize the initial chaotic orbit of Neith and to bring it down within several radii of Venus, where tidal dissipation becomes more efficient.

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Ksanfomality, Leonid. "Hypothetic Life Detected on the Planet Venus." International Letters of Chemistry, Physics and Astronomy 15 (September 2013): 76–89. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.15.76.

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Discovery and characterizations of extrasolar planets suppose that some of them possess physical conditions close to those of Venus. Therefore, the planet Venus, with its dense and hot (735 K) oxygen-free atmosphere of CO2 (mostly), having a high pressure of 9.2 MPa at the surface can be a natural laboratory for this kind of studies. On October 22/25, 1975 and March 1/5, 1982, experiments in television photography instrumented by the landers Venera-9, -10, -13 and -14 [1], yielded in large number of panoramas of the Venus surface (or their fragments) at the landing site. Over the past 31 and 38 years, no similar missions have been sent to Venus. In connection with the interest in what kind of life is possible existing on some of the exoplanets, the VENERA panoramas fit for analysis were re-processed and re-examined. A few relatively large objects were found with size ranging from a decimeter to half meter and with unusual morphology. The objects were observed in some images, but were absent in the other or altered their shape. Some of them were reviewed in Ksanfomality, 2012. Important is a search of Venusian flora. The article presents some of the obtained results.

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Ksanfomality, Leonid. "Hypothetic Life Detected on the Planet Venus." International Letters of Chemistry, Physics and Astronomy 15 (June 29, 2013): 76–89. http://dx.doi.org/10.56431/p-u2wmr7.

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Discovery and characterizations of extrasolar planets suppose that some of them possess physical conditions close to those of Venus. Therefore, the planet Venus, with its dense and hot (735 K) oxygen-free atmosphere of CO2 (mostly), having a high pressure of 9.2 MPa at the surface can be a natural laboratory for this kind of studies. On October 22/25, 1975 and March 1/5, 1982, experiments in television photography instrumented by the landers Venera-9, -10, -13 and -14 [1], yielded in large number of panoramas of the Venus surface (or their fragments) at the landing site. Over the past 31 and 38 years, no similar missions have been sent to Venus. In connection with the interest in what kind of life is possible existing on some of the exoplanets, the VENERA panoramas fit for analysis were re-processed and re-examined. A few relatively large objects were found with size ranging from a decimeter to half meter and with unusual morphology. The objects were observed in some images, but were absent in the other or altered their shape. Some of them were reviewed in Ksanfomality, 2012. Important is a search of Venusian flora. The article presents some of the obtained results.

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Ipatov, Sergei I. "Collision probabilities of migrating small bodies and dust particles with planets." Proceedings of the International Astronomical Union 5, S263 (August 2009): 41–44. http://dx.doi.org/10.1017/s174392131000147x.

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AbstractProbabilities of collisions of migrating small bodies and dust particles produced by these bodies with planets were studied. Various Jupiter-family comets, Halley-type comets, long-period comets, trans-Neptunian objects, and asteroids were considered. The total probability of collisions of any considered body or particle with all planets did not exceed 0.2. The amount of water delivered from outside of Jupiter's orbit to the Earth during the formation of the giant planets could exceed the amount of water in Earth's oceans. The ratio of the mass of water delivered to a planet by Jupiter-family comets or Halley-type comets to the mass of the planet can be greater for Mars, Venus, and Mercury, than that for Earth.

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Ga, Dheebakaran, Kokilavani S, Santosh Ganapati Patil, Sankar T, Rathika K, Arul Prasath S, Balamurali B, and Sathyamoorthy N.K. "Planet activeness: a new concept to enhance the accuracy of Astromet weather forecast." F1000Research 13 (July 5, 2024): 746. http://dx.doi.org/10.12688/f1000research.149941.1.

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Background Astrometeorology is an ancient science, that deals the relationship between planet position and weather events. Several Indian studies proved that Astrometeorology could be a complementary method to improve numerical weather forecast accuracy. Since 2011, Tamil Nadu Agricultural University is conducting astrometeorological research and devised a novel concept “Planet Activeness Chart”. The principle is that “planets’ influence on a location’s weather varies throughout the day and may be negative, inactive, active, highly active and rule depending on their angle to that location”. Most existing astromet studies used planetary position to predict the occurrence of weather events (yes/no) but failed to capture intensity of the event. The “Planet Activeness Concept” could address this limitation and enhance forecast usability. Methods A study was carried out from 2018 to 2021 with six years data (2011-16) to verify the “Planet activeness” on hourly rainfall and windspeed events in Tamil Nadu. The frequency of planet activeness for a weather event was calculated by dividing the number of times a planet was in the selected activeness during a specific event category by the total number of events. Results The results indicated that negative state of the Sun, active status of the Saturn, Uranus, Venus and Moon were positively associated with rainfall intensity. The windy planet Mercury and Neptune at active state, the Sun and Saturn at rule state, Venus and Uranus at negative state, Jupiter at highly active state had significant influence on the increased wind speed. Conclusion Applying the planet activeness concept with azimuth could enhance the accuracy and usability of Astrometeorological forecasts. This study establishes a mathematical relationship between planet activeness and weather as a first step to understand the science behind this relationship. It is suggested to study different combination of planet activeness during a weather event for more insights.

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Bolmont, E., S. N. Breton, G. Tobie, C. Dumoulin, S. Mathis, and O. Grasset. "Solid tidal friction in multi-layer planets: Application to Earth, Venus, a Super Earth and the TRAPPIST-1 planets." Astronomy & Astrophysics 644 (December 2020): A165. http://dx.doi.org/10.1051/0004-6361/202038204.

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With the discovery of TRAPPIST-1 and its seven planets residing within 0.06 au, it is becoming increasingly necessary to carry out correct treatments of tidal interactions. The eccentricity, rotation, and obliquity of the planets of TRAPPIST-1 do indeed result from the tidal evolution over the lifetime of the system. Tidal interactions can also lead to tidal heating in the interior of the planets (as for Io), which may then be responsible for volcanism or surface deformation. In the majority of studies aimed at estimating the rotation of close-in planets or their tidal heating, the planets are considered as homogeneous bodies and their rheology is often taken to be a Maxwell rheology. Here, we investigate the impact of taking into account a multi-layer structure and an Andrade rheology in the way planets dissipate tidal energy as a function of the excitation frequency. We use an internal structure model, which provides the radial profile of structural and rheological quantities (such as density, shear modulus, and viscosity) to compute the tidal response of multi-layered bodies. We then compare the outcome to the dissipation of a homogeneous planet (which only take a uniform value for shear modulus and viscosity). We find that for purely rocky bodies, it is possible to approximate the response of a multi-layer planet by that of a homogeneous planet. However, using average profiles of shear modulus and viscosity to compute the homogeneous planet response leads to an overestimation of the averaged dissipation. We provide fitted values of shear modulus and viscosity that are capable of reproducing the response of various types of rocky planets. However, we find that if the planet has an icy layer, its tidal response can no longer be approximated by a homogeneous body because of the very different properties of the icy layers (in particular, their viscosity), which leads to a second dissipation peak at higher frequencies. We also compute the tidal heating profiles for the outer TRAPPIST-1 planets (e to h).

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Svedhem, Håkan, Dmitry V. Titov, Fredric W. Taylor, and Olivier Witasse. "Venus as a more Earth-like planet." Nature 450, no. 7170 (November 2007): 629–32. http://dx.doi.org/10.1038/nature06432.

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Stofan, E. R. "Venus: Divergent outcomes of terrestrial planet formation." Journal de Physique IV (Proceedings) 139, no. 1 (December 2006): 9–19. http://dx.doi.org/10.1051/jp4:2006139003.

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Jontof-Hutter, Daniel. "The Compositional Diversity of Low-Mass Exoplanets." Annual Review of Earth and Planetary Sciences 47, no. 1 (May 30, 2019): 141–71. http://dx.doi.org/10.1146/annurev-earth-053018-060352.

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Low-mass planets have an extraordinarily diverse range of bulk compositions, from primarily rocky worlds to those with deep gaseous atmospheres. As techniques for measuring the masses of exoplanets advance the field toward the regime of rocky planets, from ultrashort orbital periods to Venus-like distances, we identify the bounds on planet compositions, where sizes and incident fluxes inform bulk planet properties. In some cases, the precision of measurement of planet masses and sizes is approaching the theoretical uncertainties in planet models. An emerging picture explains aspects of the diversity of low-mass planets, although some problems remain: Do extreme low-density, low-mass planets challenge models of atmospheric mass loss? Are planet sizes strictly separated by bulk composition? Why do some stellar characterizations differ between observational techniques? With the Transiting Exoplanet Survey Satellite ( TESS) mission, low-mass exoplanets around the nearest stars will soon be discovered and characterized with unprecedented precision, permitting more detailed planetary modeling and atmospheric characterization of low-mass exoplanets than ever before. ▪ Following the Kepler mission, studies of exoplanetary compositions have entered the terrestrial regime. ▪ Low-mass planets have an extraordinary range of compositions, from Earth-like mixtures of rock and metal to mostly tenuous gas. ▪ The TESS mission will discover low-mass planets that can be studied in more detail than ever before.

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Beard, Corey, Paul Robertson, Shubham Kanodia, Jack Lubin, Caleb I. Cañas, Arvind F. Gupta, Rae Holcomb, et al. "GJ 3929: High-precision Photometric and Doppler Characterization of an Exo-Venus and Its Hot, Mini-Neptune-mass Companion." Astrophysical Journal 936, no. 1 (August 30, 2022): 55. http://dx.doi.org/10.3847/1538-4357/ac8480.

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Abstract We detail the follow-up and characterization of a transiting exo-Venus identified by TESS, GJ 3929b (TOI-2013b), and its nontransiting companion planet, GJ 3929c (TOI-2013c). GJ 3929b is an Earth-sized exoplanet in its star’s Venus zone (P b = 2.616272 ± 0.000005 days; S b = 17.3 − 0.7 + 0.8 S ⊕) orbiting a nearby M dwarf. GJ 3929c is most likely a nontransiting sub-Neptune. Using the new, ultraprecise NEID spectrometer on the WIYN 3.5 m Telescope at Kitt Peak National Observatory, we are able to modify the mass constraints of planet b reported in previous works and consequently improve the significance of the mass measurement to almost 4σ confidence (M b = 1.75 ± 0.45 M ⊕). We further adjust the orbital period of planet c from its alias at 14.30 ± 0.03 days to the likely true period of 15.04 ± 0.03 days, and we adjust its minimum mass to m sin i = 5.71 ± 0.92 M ⊕. Using the diffuser-assisted ARCTIC imager on the ARC 3.5 m telescope at Apache Point Observatory, in addition to publicly available TESS and LCOGT photometry, we are able to constrain the radius of planet b to R p = 1.09 ± 0.04 R ⊕. GJ 3929b is a top candidate for transmission spectroscopy in its size regime (TSM = 14 ± 4), and future atmospheric studies of GJ 3929b stand to shed light on the nature of small planets orbiting M dwarfs.

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Zhu, Xiangzhao. "Comparison Of Formation, Atmosphere and Habitability for Mercury and Venus." Highlights in Science, Engineering and Technology 38 (March 16, 2023): 653–58. http://dx.doi.org/10.54097/hset.v38i.5918.

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The solar system has very strong relationship with human. All the factors in it creates the distinctive circumstances for all life on Earth to survive. This study picks two planets in the solar system, i.e., Mercury and Venus, to discuss and compare on three features from the perspective of formation, atmosphere and habitability. According to the analysis, either planet is suitable for life’s existence or human’s residence based on the state-of-art techniques. To be specific, Mercury’s formation is still a problem to be solved while Venus’ is much clearer. Venus’ thicker atmosphere contains CO2, N2 and sulfuric chemicals as well as PH3, an indicator for the improbable life. Mercury’s atmosphere is rather poor, but is important partly because it can offer information of the planet’s formation. This article can help beginners obtain an understanding about two planets’ features in three aspects and aid students on similar topics. Overall, these results shed light on guiding further exploration of solar system.

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Ksanfomality, Leonid V. "Possible Signs of Life on the Planet Venus." International Journal of Astronomy and Astrophysics 03, no. 01 (2013): 57–79. http://dx.doi.org/10.4236/ijaa.2013.31007.

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Ksanfomality, L. V. "Possible detection of life on the planet venus." Doklady Physics 57, no. 9 (September 2012): 367–72. http://dx.doi.org/10.1134/s1028335812090029.

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Mulholland, Philip, and Stephen Paul Rathbone Wilde. "Inverse Climate Modelling Study of the Planet Venus." International Journal of Atmospheric and Oceanic Sciences 4, no. 1 (2020): 20. http://dx.doi.org/10.11648/j.ijaos.20200401.13.

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Nakamura, Masato, Takeshi Imamura, Munetaka Ueno, Naomoto Iwagami, Takehiko Satoh, Shigeto Watanabe, Makoto Taguchi, et al. "Planet-C: Venus Climate Orbiter mission of Japan." Planetary and Space Science 55, no. 12 (October 2007): 1831–42. http://dx.doi.org/10.1016/j.pss.2007.01.009.

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32

Williams, Sarah. "Sister planet: Mission to Venus reveals watery past." Science News 172, no. 22 (December 1, 2007): 339. http://dx.doi.org/10.1002/scin.2007.5591722202.

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Voosen, Paul. "Active volcano shows Venus is a living planet." Science 379, no. 6637 (March 17, 2023): 1076–77. http://dx.doi.org/10.1126/science.adh7974.

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Xie, Wenbin, Costantino Sigismondi, Xiaofan Wang, and Paolo Tanga. "Venus transit, aureole and solar diameter." Proceedings of the International Astronomical Union 8, S294 (August 2012): 485–86. http://dx.doi.org/10.1017/s1743921313002986.

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AbstractThe possibility to measure the solar diameter using the transits of Mercury has been exploited to investigate the past three centuries of its evolution and to calibrate these measurements made with satellites. This measurement basically consists to compare the ephemerides of the internal contact timings with the observed timings. The transits of Venus of 2004 and 2012 gave the possibility to apply this method, involving a planet with atmosphere, with the refraction of solar light through it creating a luminous arc all around the disk of the planet. The observations of the 2012 transit made to measure the solar diameter participate to the project Venus Twilight Experiment to study the aureole appearing around it near the ingress/egress phases.

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Yatsenko, M. Yu, V. A. Vorontsov, and V. V. Ryzhkov. "System engineering research of a multirotor aircraft as a prospective technical means of exploring the atmosphere and surface of the planet Venus." Spacecrafts & Technologies 7, no. 3 (September 26, 2023): 220–26. http://dx.doi.org/10.26732/j.st.2023.3.06.

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Currently, the exploration of the planet Venus is a very relevant and developing direction in space science. The development of rocket and space technologies has expanded the boundaries of accessibility of spacecraft to objects in the Solar System, allow for entire interplanetary expeditions, including flights to terrestrial planets, giant planets, and the outskirts of the Solar System. Currently, a program of planetary exploration for the next decades is being formed. Studying the history of expeditions to Venus and Mars clarifies the need to develop and improve methods for studying the atmosphere of the nearest planets to Earth, in particular, Venus, using vailable technical means, making them as efficient as possible. The exploration of Venus is proposed to be carried out using a technical means– a multirotor aircraft. This object is allocated as a system, and its role in the composition of the supersystem is also defined and described. The paper identifies scenarios for the functioning of the flying apparatus are highlighted, the tasks of its subsystems are described, as well as their interaction with each other. The main external factors affecting the work of the subsystems of the multirotor aircraft are presented. A functional scheme of the system is developed, as well as the main indicators used to assess the effectiveness of achieving the target task. This work is a preliminary stage before building a mathematical model.

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Fang, Tong, and Hongping Deng. "Extreme close encounters between proto-Mercury and proto-Venus in terrestrial planet formation." Monthly Notices of the Royal Astronomical Society 496, no. 3 (June 20, 2020): 3781–85. http://dx.doi.org/10.1093/mnras/staa1785.

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ABSTRACT Modern models of terrestrial planet formation require solids depletion interior to 0.5–0.7 au in the planetesimal disc to explain the small mass of Mercury. The Earth and Venus analogues emerge after ∼100 Myr collisional growth, while Mercury forms in the diffusive tails of the planetesimal disc. We carried out 250 N-body simulations of planetesimal discs with mass confined to 0.7–1.0 au to study the statistics of close encounters that were recently proposed as an explanation for the high iron mass fraction in Mercury. We formed 39 Mercury analogues in total and all proto-Mercury analogues were scattered inwards by proto-Venus. Proto-Mercury typically experiences six extreme close encounters (closest approach smaller than six Venus radii) with Proto-Venus after Proto-Venus acquires 0.7 Venus Mass. At such close separation, the tidal interaction can already affect the orbital motion significantly such that the N-body treatment itself is invalid. More and closer encounters are expected should tidal dissipation of orbital angular momentum accounted. Hybrid N-body hydrodynamic simulations, treating orbital and encounter dynamics self-consistently, are desirable to evaluate the degree of tidal mantle stripping of proto-Mercury.

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Klimczak, Christian, Paul K. Byrne, A. M. Celâl Şengör, and Sean C. Solomon. "Principles of structural geology on rocky planets." Canadian Journal of Earth Sciences 56, no. 12 (December 2019): 1437–57. http://dx.doi.org/10.1139/cjes-2019-0065.

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Although Earth is the only known planet on which plate tectonics operates, many small- and large-scale tectonic landforms indicate that deformational processes also occur on the other rocky planets. Although the mechanisms of deformation differ on Mercury, Venus, and Mars, the surface manifestations of their tectonics are frequently very similar to those found on Earth. Furthermore, tectonic processes invoked to explain deformation on Earth before the recognition of horizontal mobility of tectonic plates remain relevant for the other rocky planets. These connections highlight the importance of drawing analogies between the rocky planets for characterizing deformation of their lithospheres and for describing, applying appropriate nomenclature, and understanding the formation of their resulting tectonic structures. Here we characterize and compare the lithospheres of the rocky planets, describe structures of interest and where we study them, provide examples of how historic views on geology are applicable to planetary tectonics, and then apply these concepts to Mercury, Venus, and Mars.

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Yan, Maodong, Tong Dang, Yu-Tian Cao, Jun Cui, Binzheng Zhang, Zerui Liu, and Jiuhou Lei. "A Comparative Study of Ionospheric Response to Solar Flares at Earth, Venus, and Mars." Astrophysical Journal 939, no. 1 (October 28, 2022): 23. http://dx.doi.org/10.3847/1538-4357/ac92ff.

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Abstract It has been widely recognized that the ionosphere of the terrestrial planet responds greatly to the enhanced X-ray and extreme ultraviolet radiation during solar flares. However, little attention has been paid to the comparative study of the ionospheric response between different Earth-like planets. In this work, we investigate the responses of the ionospheres of Earth, Venus, and Mars to the 2017 September 6 solar flares, with self-consistent planetary ionospheric models. The result shows that the electron density increases significantly in the relatively low ionosphere region, and its maximum relative change displays profound differences between planets. The ion temperatures at Earth and Venus share a similar response to flares, but differ from those at Mars, which relates to the background atmospheric conditions. For the electron temperature response to the X9.3 flare, at Earth it increases with a maximum magnitude of 250 K, in contrast to the decrease of ∼45 K at Venus and ∼40 K at Mars. The vertical plasma velocity at all three planets exhibits enhancement during solar flares. As a result, the upward flux increases by 2.16 × 1012 m−2 s−1 at 800 km of Earth, 3.79 × 1010 m−2 s−1, and 8.45 × 109 m−2 s−1 at 400 km of Venus and Mars. This is the first self-consistent simulation of the flare-induced enhancement of upward plasma flow at Venus and Mars.

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Shah, Oliver, Ravit Helled, Yann Alibert, and Klaus Mezger. "Possible Chemical Composition And Interior Structure Models Of Venus Inferred From Numerical Modelling." Astrophysical Journal 926, no. 2 (February 1, 2022): 217. http://dx.doi.org/10.3847/1538-4357/ac410d.

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Abstract Venus’ mass and radius are similar to those of Earth. However, dissimilarities in atmospheric properties, geophysical activity, and magnetic field generation could hint toward significant differences in the chemical composition and interior evolution of the two planets. Although various explanations for the differences between Venus and Earth have been proposed, the currently available data are insufficient to discriminate among the different solutions. Here we investigate the possible range of models for Venus’ structure. We assume that core segregation happened as a single-stage event. The mantle composition is inferred from the core composition using a prescription for metal-silicate partitioning. We consider three different cases for the composition of Venus defined via the bulk Si and Mg content, and the core’s S content. Permissible ranges for the core size, mantle, and core composition as well as the normalized moment of inertia (MoI) are presented for these compositions. A solid inner core could exist for all compositions. We estimate that Venus’ MoI is 0.317–0.351 and its core size 2930–4350 km for all assumed compositions. Higher MoI values correspond to more oxidizing conditions during core segregation. A determination of the abundance of FeO in Venus’ mantle by future missions could further constrain its composition and internal structure. This can reveal important information on Venus’ formation and evolution, and, possibly, the reasons for the differences between Venus and our home planet.

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Kukanova, Viktoria V. "Астрономическая терминология монгольских языков: материалы к этимологическому словарю." Oriental studies 13, no. 6 (December 29, 2020): 1652–66. http://dx.doi.org/10.22162/2619-0990-2020-52-6-1652-1666.

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Introduction. The system of astronomical terms in Mongolic languages is structurally complicated due to multiple layers of both pre-Buddhist and Buddhist beliefs adopted by proto-Mongols. The latter had tended to revere celestial bodies and elaborated a number of cults still traceable in spiritual and material culture of descending nations. Goals. The work aims at identifying Mongolic astronomical terms and provides preliminary analyses of their semantics and etymologies. Materials and methods. The paper focuses on dictionaries of Mongolic languages, examines etymological studies and Turkic dictionaries, special attention be paid to An Etymological Dictionary of Altaic Languages. The reference proto-Mongolian lexical constructs are represented by those contained in Hans Nugteren’s Mongolic Phonology and ones reproduced by O. Mudrak (available on The Tower of Babel website). The study employs etymological and linguocultural analytical tools. Results. The astronomical system developed in ancient times contains several layers characterizing archaic perceptions and worldviews of proto-Mongols. Some astronyms — including the words for ‘sky’, ‘star’, ‘Sun’, ‘Moon’, ‘Venus’ — seem to have evolved from proto-Altaic stems. In Mongolic languages, the concept ‘planet’ proves a more recent phenomenon and initially all celestial bodies had been perceived as stars, which resulted in multiple onyms with the component odn ‘star’ (e.g., Venus, Mars, Mercury, Sun and Moon used to be identified as stars). The Earth proper was not believed to be a star or planet since it first and foremost served as home to ancient Mongols, their habitat. In subsequent eras, only visible celestial bodies — Sun, Moon, Mars, Mercury, Jupiter, Venus, Saturn — started being referred to as planets, their names employed for denoting the days of the week. The mobility of the Sun and Moon prompted proto-Mongols that the former were planets, though ancient humans rarely tended to distinguish between planets and stars as such. As for currently known planets of the Solar System, ancient Mongols were aware of Venus, Mars, Jupiter, and supposedly Mercury. It is after their conversion to Buddhism that they gained an onym denoting Saturn, while those of Neptune, Pluto, and Uranus are more recently adopted lexemes.

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Gunell, Herbert, Romain Maggiolo, Hans Nilsson, Gabriella Stenberg Wieser, Rikard Slapak, Jesper Lindkvist, Maria Hamrin, and Johan De Keyser. "Why an intrinsic magnetic field does not protect a planet against atmospheric escape." Astronomy & Astrophysics 614 (June 2018): L3. http://dx.doi.org/10.1051/0004-6361/201832934.

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The presence or absence of a magnetic field determines the nature of how a planet interacts with the solar wind and what paths are available for atmospheric escape. Magnetospheres form both around magnetised planets, such as Earth, and unmagnetised planets, like Mars and Venus, but it has been suggested that magnetised planets are better protected against atmospheric loss. However, the observed mass escape rates from these three planets are similar (in the approximate (0.5–2) kg s−1 range), putting this latter hypothesis into question. Modelling the effects of a planetary magnetic field on the major atmospheric escape processes, we show that the escape rate can be higher for magnetised planets over a wide range of magnetisations due to escape of ions through the polar caps and cusps. Therefore, contrary to what has previously been believed, magnetisation is not a sufficient condition for protecting a planet from atmospheric loss. Estimates of the atmospheric escape rates from exoplanets must therefore address all escape processes and their dependence on the planet’s magnetisation.

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Mendonça, João M., and Lars A. Buchhave. "Modelling the 3D climate of Venus with oasis." Monthly Notices of the Royal Astronomical Society 496, no. 3 (June 9, 2020): 3512–30. http://dx.doi.org/10.1093/mnras/staa1618.

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ABSTRACT Flexible 3D models to explore the vast diversity of terrestrial planets and interpret observational data are still in their early stages. In this work, we present oasis: a novel and flexible 3D virtual planet laboratory. With oasis we envision a platform that couples self-consistently seven individual modules representing the main physical and chemical processes that shape planetary environments. Additionally, oasis is capable of producing simulated spectra from different instruments and observational techniques. In this work, we focus on the benchmark test of coupling four of the physical modules: fluid dynamics, radiation, turbulence, and surface/soil. To test the oasis platform, we produced 3D simulations of the Venus climate and its atmospheric circulation and study how the modelled atmosphere changes with various cloud covers, atmospheric heat capacity, and surface friction. 3D simulations of Venus are challenging because they require long integration times with a computationally expensive radiative transfer code. By comparing oasis results with observational data, we verify that the new model is able to successfully simulate Venus. With simulated spectra produced directly from the 3D simulations, we explore the capabilities of future missions, like LUVOIR, to observe Venus analogues located at a distance of 10 pc. With oasis, we have taken the first steps to build a sophisticated and very flexible platform capable of studying the environment of terrestrial planets, which will be an essential tool to characterize observed terrestrial planets and plan future observations.

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43

Voosen, Paul. "Jilted again, Venus scientists pine for their neglected planet." Science 355, no. 6321 (January 12, 2017): 116–17. http://dx.doi.org/10.1126/science.355.6321.116.

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TITOV, Dmitri, and Håkan SVEDHEM. "Venus Express: a Fascinating Journey to Our Planet-neighbor." TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN 8, ists27 (2010): Tk_39—Tk_46. http://dx.doi.org/10.2322/tastj.8.tk_39.

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45

Ishii, N., H. Yamakawa, S. Sawai, M. Shida, T. Hashimoto, M. Nakamura, T. Imamura, T. Abe, K. Oyama, and I. Nakatani. "Current status of the PLANET-C Venus orbiter design." Advances in Space Research 34, no. 8 (January 2004): 1668–72. http://dx.doi.org/10.1016/j.asr.2004.07.006.

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46

Drake, Nadia. "Venus unveiled: Spacecraft finds Earthy features on sister planet." Science News 180, no. 12 (November 29, 2011): 26–27. http://dx.doi.org/10.1002/scin.5591801223.

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Fys, M. M., P. M. Zazuliak, and A. R. Sohor. "Gravity potential and its component of centrifugal force inside the ellipsoidal planet." Kosmìčna nauka ì tehnologìâ 28, no. 4 (August 9, 2022): 71–77. http://dx.doi.org/10.15407/knit2022.04.071.

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A method for determining the gravitational potential of a celestial body whose surface is a sphere or ellipsoid with an abrupt mass distribution function is proposed. For these cases, the formulas for determining the internal potential and gravity are obtained. The calculations performed according to these formulas make it possible to analyze the contribution of the ellipticity of the planet to the value of its internal potential and compare it with the magnitude of the centrifugal force for the planets of the Earth group (Earth, Mars, Venus) and the Moon.

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Lenardic, A., and J. Seales. "Habitability: a process versus a state variable framework with observational tests and theoretical implications." International Journal of Astrobiology 20, no. 2 (January 21, 2021): 125–32. http://dx.doi.org/10.1017/s1473550420000415.

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The term habitable is used to describe planets that can harbour life. Debate exists as to specific conditions that allow for habitability but the use of the term as a planetary variable has become ubiquitous. This paper poses a meta-level question: What type of variable is habitability? Is it akin to temperature, in that it is something that characterizes a planet, or is something that flows through a planet, akin to heat? That is, is habitability a state or a process variable? Forth coming observations can be used to discriminate between these end-member hypotheses. Each has different implications for the factors that lead to differences between planets (e.g. the differences between Earth and Venus). Observational tests can proceed independent of any new modelling of planetary habitability. However, the viability of habitability as a process can influence future modelling. We discuss a specific modelling framework based on anticipating observations that can discriminate between different views of habitability.

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Ezcurdia, Maite. "Modos de presentación y modos de determinación." Crítica (México D. F. En línea) 27, no. 80 (January 8, 1995): 57–96. http://dx.doi.org/10.22201/iifs.18704905e.1995.992.

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In this paper I argue that, in order to make (T1) and (T2) compatible within a Fregean approach, we must reject the view that all modes of presentation are senses. (T1) There is a diversity of ways in which Venus may be presented to each subject, and which are associated with the name ‘Venus’. (T2) There is only one Fregean thought expressed by the sentence ‘Venus is a planet’. Modes of presentation are those things which are essentially psychological and have causal powers on minds. The mind of a subject is sensitive to differences in modes of presentation, so that if an object is presented to a subject under different modes of presentation and she has no reason to believe that they are modes of presentation of one and the same object, then she may take opposing attitudes involving those different modes of presentation. In contrast, senses are those things which are essentially semantic. For this reason, I propose that they be understood as certain ways of determining the reference of terms, and either are given by the semantic rules for those terms or are identical to those semantic rules. I agree with McDowell that an interpretive truth-theory for a language L gives us a theory of sense for L, and that something like (V) ‘Venus’ refers to Venus will give us the axiom which assigns the semantic value for ‘Venus’ within such a theory, and which is necessary in order to derive the interpretive truth-conditions of a sentence like ‘Venus is a planet’. An axiom like ‘Venus’ refers to Hesperus will not do within a theory of sense. Nonetheless, it will do within a theory of reference, a truth-theory which delivers not interpretive truth-conditions, but purely referential truth conditions. The purely referential truth-conditions for an indicative atomic sentence are, I claim, those which are specified by specifying those features in the world (objects, properties, etc.) to which the meaningful parts of the sentence refer, representing them as related in a certain way. For the specification of such truth-conditions, the difference in cognitive value between two sentences will not matter, whereas it will matter for the specification of interpretive truth-conditions. Now, senses are introduced to allow for an explanation of the difference in cognitive value between sentences with the same purely referential truth-conditions. An indication of when two sentences differ in cognitive value is when it is possible for a subject who is rational and understands the language in question to take opposing attitudes to those sentences (or their contents —whatever those contents are); and if there is in fact such a subject who takes opposing attitudes to those sentences, then those sentences differ in their cognitive value. Given this connection between cognitive value and a subject’s attitudes, and given the purpose for which senses are introduced, we must suppose that a subject’s mind must be sensitive to differences in senses, and so, that senses must be psychologically relevant. My proposal, which aims to establish some kind of identity between some modes of presentation under certain conditions and those ways of determination which are senses, is as follows: A psychological mode of presentation M is a way of determination which is a sense relative to a particular expression e in a public language L which aids in expressing propositional attitude P if and only if i the subject who has M and who is sufficiently competent in L knows (or realizes) that M goes with e in L; ii no other proposition e′ in L is more adequate for reporting the subject’s propositional attitude P; iii M is crucial in the subject’s rational failure to make certain identifications; and iv M is an appropriate function to an appropriate reference. Only the mode of presentation associated with ‘Venus’ that satisfies conditions i-iv relative to ‘Venus’ which aids in expressing a propositional attitude like the belief that Venus is a planet, will be the sense of ‘Venus’. I argue that only the mode of presentation of Venus as Venus will do, and that such mode of presentation is implicit in the way of determination shown by (V). Other modes of presentation of Venus as being big or appearing in the sky in the evenings or being the second planet in proximity to the sun will not satisfy conditions i–iv. Thus, although a subject may have all these modes of presentation of Venus and associate them with ‘Venus’ (i.e. (T1)), only the mode of presentation of Venus as Venus will do as the sense of ‘Venus’. Hence, only one thought will be expressed by a sentence like ‘Venus is a planet’ (i.e. (T2)).

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Udalski, A., Y. K. Jung, C. Han, A. Gould, S. Kozłowski, J. Skowron, R. Poleski, et al. "A VENUS-MASS PLANET ORBITING A BROWN DWARF: A MISSING LINK BETWEEN PLANETS AND MOONS." Astrophysical Journal 812, no. 1 (October 8, 2015): 47. http://dx.doi.org/10.1088/0004-637x/812/1/47.

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Journal articles on the topic 'Venus (Planet)'

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