Crafted from silicone, each dual mold makes two icy Millennium Falcons that you can plop inside your favorite librations — whiskey, blue milk, whatever.
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But the Moon is basically locked with the same face pointing to the Earth, except that in practice there are small "librations" where the Moon wobbles a little back and forth—and these turn out to be particularly troublesome to predict.
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Kopff lies along the eastern inner edge, and Maunder on the northern inner side. Smaller craters include Lallemand to the northeast, Shuleykin to the south, and Fryxell in the west. Out of sight from the Earth, even during favorable librations, are the craters Lowell to the northwest, and Golitsyn to the west-southwest.
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The lunar phases and librations in 2020 as viewed from the Northern Hemisphere at hourly intervals, with titles and supplemental graphics The lunar phases and librations in 2020 as viewed from the Southern Hemisphere at hourly intervals, with titles and supplemental graphics full Moon sets behind San Gorgonio Mountain (in California) on a midsummer's morning. The lunar phase or Moon phase is the shape of the directly sunlit portion of the Moon as viewed from Earth. The lunar phases gradually change over the period of a synodic month (about 29.53 days), as the orbital positions of the Moon around Earth and of Earth around the Sun shift. The Moon's rotation is tidally locked by Earth's gravity; therefore, most of the same lunar side always faces Earth.
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Babcock, facing west, with Zasyadko at center, from Apollo 11 Zasyadko is a small lunar impact crater located to the northeast of Mare Smythii. It lies beyond the eastern lunar limb in an area that is only visible during favorable librations. It is located entirely within the crater Babcock. To the southwest is McAdie.
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Cassini's laws provide a compact description of the motion of the Moon. They were established in 1693 by Giovanni Domenico Cassini, a prominent scientist of his time.For the original statement of the laws, see Refinements of these laws to include physical librations have been made, and they have been generalized to treat other satellites and planets.
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From 2015 onwards this ephemeris is utilized in Astronomical Almanac. Beginning with this release only Mars' Barycenter was included due to the small masses of its moons Phobos and Deimos which create a very small offset from the planet's center. The complete ephemerides files is 128 megabytes but several alternative versions have been made available by JPL DE432 was created April 2014. It includes librations but no nutations.
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Pasteur is a large lunar impact crater, approximately 233 kilometers in diameter, belonging to the category termed a walled plain. It was named after French chemist and microbiologist Louis Pasteur. It lies on the far side of the Moon as seen from the Earth, just beyond the eastern limb. The vicinity of this crater is occasionally brought into view from Earth due to librations, although not much detail can be seen.
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However, proving that a body is in hydrostatic equilibrium is extremely difficult, but by using a combination of shape and gravity data, the hydrostatic contributions can be deduced. Specific techniques to detect inner oceans include magnetic induction, geodesy, librations, axial tilt, tidal response, radar sounding, compositional evidence, and surface features. Artist's cut-away representation of the internal structure of Ganymede, with a liquid water ocean "sandwiched" between two ice layers. Layers drawn to scale.
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Lunar Orbiter 4 image Hohmann is a lunar impact crater that lies within the central basin of the Mare Orientale formation, on the farside of the Moon. It is located to the south of the crater Maunder, and to the west of Kopff crater. Due to its proximity to the western lunar limb, this area of the surface is occasionally visible during favorable librations. However the basin is viewed from the side, restricting the amount of detail that can be observed from Earth.
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Arrhenius is a lunar impact crater that is located just on the far side of the Moon, near the southwest limb. In this location the vicinity of the crater can be viewed during favorable librations, although it is viewed from on edge. To the south-southeast is the worn crater Blanchard, and De Roy lies further to the west. The outer wall of Arrhenius has been somewhat worn and eroded due to a history of minor impacts, leaving the rim rounded and low.
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Oblique Lunar Orbiter 4 image centered on Riemann with Beals at lower left Beals is a lunar impact crater that is located near the eastern limb of the Moon, and lies across the southwestern rim of the crater Riemann. From the Earth the crater is viewed nearly from on edge, and is best seen during favorable librations. To the west is the large walled plain Gauss. This crater formation is only lightly worn, with no significant impacts within its perimeter.
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LRO Couder is a small lunar impact crater that is located just behind the western limb of the Moon, in a region of the surface that is brought into view during favorable librations. It lies on the inner foothills of the Montes Cordillera, a ring-shaped mountain range that surrounds the Mare Orientale impact basin. This region is relatively devoid of major craters, with the nearest being Schlüter almost due east. Slightly farther to the south of Couder is Maunder, at the edge of the mare.
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Lunar laser ranging data for the Moon was added for the first time since DE403, significantly improving the lunar orbit and librations. Estimated position data from the Cassini spacecraft was included in the fit, improving the orbit of Saturn, but rigorous analysis of the data was deferred to a later date. DE418 covered the years 1899 to 2051, and JPL recommended not using it outside of that range due to minor inconsistencies which remained in the planets' masses due to time constraints. DE421 was released in 2008.
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Lunar Orbiter 4 image Maunder is a lunar impact crater that is located on the far side of the Moon, just beyond the western limb. This region is sometimes brought into view during favorable librations, but not much detail can be seen. The crater lies at the northern end of the Mare Orientale, within the ring of mountains named Montes Rook, and it is the largest crater on this lunar mare. To the southeast is the crater Kopff, and due south is the small Hohmann.
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Kramarov is a small lunar impact crater that is located on the far side of the Moon. It lies just beyond the western limb, at the far edge of the region that is brought into view during favorable librations. The crater is situated in the northern part of the Montes Cordillera, the outer ring of the mountains that surround Mare Orientale. In the past this crater was designated Lents K, a satellite of Lents which lies to the northwest, before being named by the IAU.
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LRO mosaic Bohr is a lunar impact crater that is located near the western lunar limb, in the area that is affected by librations. It is attached to the southwestern rim of the larger, eroded Vasco da Gama formation, and to the southeast of the crater Einstein. The crater was observed for the first time in 1963 by Arthus and Ewen Whitaker in the book Rectified Lunar Atlas. The rim of Bohr is worn and eroded, and a pair of small, bowl-shaped craters lies across the western rim.
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Drude is a lunar impact crater that lies on the far side of the Moon, in the rugged Montes Cordillera range that forms the outer ring around the Mare Orientale impact basin. It is located just behind the west-southwest limb, and this area is sometimes brought into sight from Earth during favorable librations. However, even at such times, the crater is viewed from the edge and little detail can be seen. This is a circular crater with a relatively sharp edge, sloping inner walls and a fairly level interior.
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From 1910 onwards Kasprowy Wierch became very popular among ski tourists so much so an aerial tramway or téléphérique, reaching almost to the summit, was built between 1935-1936 as such it is one of the oldest in Europe. As part of its modernization, the cabin aerial ropeway was closed for a period until December 2007. In 1938 meteorological and astronomical observatories were built here. One of the faint Kordylewski clouds, at or circling the L4 and L5 librations points of the moon, was first photographed here by Kazimierz Kordylewski in 1961.
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Oblique Apollo 15 image, facing south Donner is a lunar impact crater on the far side of the Moon. It is located just to the northeast of the Mare Australe, behind the southeastern limb of the Moon. During favorable librations this part of the lunar surface can be brought into view of the Earth, but the site is viewed from the edge and so not much detail can be seen. This crater has a moderately eroded outer rim, and several small and tiny craterlets lie along the edge.
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Oblique view of Al-Biruni crater facing north, from Apollo 17 Oblique Apollo 14 Hasselblad camera image Al-Biruni is an impact crater that lies on the far side of the Moon, just beyond the eastern limb. This portion of the surface is sometimes brought into sight due to librations of the Moon, but due to its location the crater is viewed from the side. Al-Biruni lies to the south of the crater Joliot, and to the northeast of Goddard. It is named after the great Ghaznavid Scientist Al-Biruni.
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Oblique Lunar Orbiter 4 image of Goddard (large crater at left) and Ibn Yunus (right) Goddard is a lunar impact crater that is located along the eastern limb of the Moon, and so is visible from the edge from Earth. It is best viewed during favorable librations when the orientation of the Moon brings it further into sight. The crater is located in the Mare Marginis, to the northeast of the prominent crater Neper. Ibn Yunus, a crater remnant, is attached to the southeastern rim and is partly overlaid by Goddard.
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Babcock is located in a region of the Moon's surface that is occasionally brought into view during favorable librations, although it is seen from the edge and so little detail can be discerned from an observer on the Earth. LRO image The rim of Babcock has been eroded, notched and modified by subsequent impacts, leaving a somewhat irregular and uneven outer rim. The interior has been resurfaced by lava flows, and is relatively flat. In place of a central peak, a small crater lies very close to the crater midpoint.
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DE430 Lunar Orbit, Physical Librations, and Surface Coordinates p.10. "These derived values depend on a theory which is not accurate to the number of digits given." See also : Chapront, Chapront-Touzé, Francou (2002). A new determination of lunar orbital parameters, precession constant and tidal acceleration from LLR measurements : +38.08 ± 0.04 mm/yr in the mean Earth–Moon distance This is consistent with results from satellite laser ranging (SLR), a similar technique applied to artificial satellites orbiting Earth, which yields a model for the gravitational field of Earth, including that of the tides.
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Tycho's distinctive contributions to lunar theory include his discovery of the variation of the Moon's longitude. This represents the largest inequality of longitude after the equation of the center and the evection. He also discovered librations in the inclination of the plane of the lunar orbit, relative to the ecliptic (which is not a constant of about 5° as had been believed before him, but fluctuates through a range of over a quarter of a degree), and accompanying oscillations in the longitude of the lunar node. These represent perturbations in the Moon's ecliptic latitude.
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Oblique view facing south Lorentz is a huge lunar impact crater that lies just beyond the northwest limb of the Moon, in a region that is brought into sight of the Earth during favorable librations. This formation is nearly as large as the Mare Nectaris on the near side of the Moon, although it has not been submerged by lava as have the lunar mare. Sections of the crater floor are, however, relatively level, particularly an arc along the western rim. But this last region is still marked by a number of tiny craterlets.
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Kepler-80 d, e, b, c and g have orbits locked in a resonance. While their periods are in a ~ 1.000: 1.512: 2.296: 3.100: 4.767 ratio, in a frame of reference that rotates with the conjunctions this reduces to a ratio of 4:6:9:12:18. Conjunctions of d and e, e and b, b and c, and c and g occur at relative intervals of 2:3:6:6 in a pattern that repeats about every 191 days. Librations of possible three-body resonances have amplitudes of only about 3 degrees, and modeling indicates the resonant system is stable to perturbations.
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Solar eclipses on the Moon are caused when the planet Earth passes in front of the Sun and blocks its light. Viewers on Earth experience a lunar eclipse during a solar eclipse on the moon. These solar eclipses are only seen in the near side portion and smaller parts of the far side where Earth is seen during librations, these areas of the moon making up the visible portion of the Moon. Eclipses there are seen during the lunar sunrise and sunset and extend to the furthermost areas of the near side but mainly not in the polar areas of the Moon.
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About ninety-one percent of the far side never experiences solar eclipses as the Earth is never seen there because the limit of the view of the planet during librations is about eight degrees within the near side. Eclipses are generally not seen in the fringes of the near side, within the far side, or in the lower and most of the middle parts. Around it, it is not seen in the lower parts. In that location and around it, the eclipses are never seen in most crater hollows or some of the lowest parts of some crater hollows.
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Oblique Apollo 14 Hasselblad camera image Edison is right of center, Edison T is left of center Edison is a lunar impact crater on the far side of the Moon. It is located just behind the north- northeastern limb of the Moon, a region that is sometimes brought into sight from Earth during favorable librations. However even at such times not much detail can be discerned, and the crater is better observed by orbiting spacecraft. The Edison crater is attached to the southeastern outer rim of the crater Lomonosov, to the east of the walled plain Joliot.
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Differentiation itself is evaluated indirectly, by the mineralogy of a body's surface, versus its expected bulk density and mineralogy, or via shape effects due to slight variations in gravity. Differentiation may also be measured directly, by the higher-order terms of a body's gravity field as measured by a flyby or gravitational assist, and in some cases by librations. Edge cases include Vesta and some of the larger moons, which show differentiation but are assumed to have since fully solidified. The question of whether Earth's Moon has solidified, or retains some molten layers, has not been definitively answered.
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The October 7, 1959, image by Luna 3 which revealed, for the first time, the far side of the Moon Until the late 1950s, little was known about the far side of the Moon. Librations of the Moon periodically allowed limited glimpses of features near the lunar limb on the far side, but only up to 59% of the total surface of the moon. These features, however, were seen from a low angle, hindering useful observation (It proved difficult to distinguish a crater from a mountain range). The remaining 82% of the surface on the far side remained unknown, and its properties were subject to much speculation.
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Despite the Moon's rotational and orbital periods being exactly locked, about 59 percent of the Moon's total surface may be seen with repeated observations from Earth, due to the phenomena of libration and parallax. Librations are primarily caused by the Moon's varying orbital speed due to the eccentricity of its orbit: this allows up to about 6° more along its perimeter to be seen from Earth. Parallax is a geometric effect: at the surface of Earth we are offset from the line through the centers of Earth and Moon, and because of this we can observe a bit (about 1°) more around the side of the Moon when it is on our local horizon.
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Jet Propulsion Laboratory Development Ephemeris (abbreved JPL DE(number), or simply DE(number)) designates one of a series of mathematical models of the Solar System produced at the Jet Propulsion Laboratory in Pasadena, California, for use in spacecraft navigation and astronomy. The models consist of numeric representations of positions, velocities and accelerations of major Solar System bodies, tabulated at equally spaced intervals of time, covering a specified span of years. Barycentric rectangular coordinates of the Sun, eight major planets and Pluto, and geocentric coordinates of the Moon are tabulated. DE405, created in May 1997, include both nutations and librations, and is considered the fundamental planetary and lunar ephemerides of The Astronomical Almanac.
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A least-squares technique was used to perform the fitting. As of DE421, perturbations from 343 asteroids, representing about 90% of the mass of the main asteroid belt, have been included in the dynamical model. The physics modeled included the mutual Newtonian gravitational accelerations and their relativistic corrections (a modified form of the Einstein-Infeld-Hoffmann equation), the accelerations caused by the tidal distortion of the Earth, the accelerations caused by the figure of the Earth and Moon, and a model of the lunar librations. The observational data in the fits has been an evolving set, including: ranges (distances) to planets measured by radio signals from spacecraft,See for a good summary of spacecraft radio-navigation.
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After Jupiter and Saturn cross the 2:1 resonance their combined gravitational influence destabilizes the Trojan co-orbital region allowing existing Trojan groups in the L4 and L5 Lagrange points of Jupiter and Neptune to escape and new objects from the outer planetesimal disk to be captured. Objects in the trojan co-orbital region undergo libration, drifting cyclically relative to the L4 and L5 points. When Jupiter and Saturn are near but not in resonance the location where Jupiter passes Saturn relative to their perihelia circulates slowly. If the period of this circulation falls into resonance with the period that the trojans librate the range of their librations can increase until they escape.
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The presence of an internal salty ocean in contact with the moon's rocky core, places Enceladus "among the most likely places in the Solar System to host alien microbial life". On June 30, 2014, NASA celebrated ten years of Cassini exploring Saturn and its moons, highlighting the discovery of water activity on Enceladus among other findings. In September 2015, NASA announced that gravitational and imaging data from Cassini were used to analyze the librations of Enceladus' orbit and determined that the moon's surface is not rigidly joined to its core, concluding that the underground ocean must therefore be global in extent. On October 28, 2015, Cassini performed a close flyby of Enceladus, coming within of the surface, and passing through the icy plume above the south pole.
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They are not usually at an exact right angle to the incoming beam, so the different corner cubes of the retroreflectors are at different distances from the transmitter. This is because the Moon, although it keeps one face to the Earth, does not do so exactly—it wobbles from side to side and up and down, by as much as 10° in magnitude. (See libration.) These librations occur since the Moon rotates at constant speed, but has an elliptical and inclined orbit. This effect may seem small, but it is not only measurable, it forms the largest unknown in finding the range, since there is no way to tell which corner cube reflected each photon. The biggest array, the Apollo 15 reflector, can have a corner-to-corner range spread of ≈ 1.2 sin (10°) m, or 210 mm, or about 1.4 ns of round-trip time.
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Surprisingly, despite its orbit being nearly in the plane of Mars's equator and despite its very close distance to Mars, there are some occasions when Phobos escapes being eclipsed. Phobos and Deimos both have synchronous rotation, which means that they have a "far side" that observers on the surface of Mars can't see. The phenomenon of libration occurs for Phobos as it does for Earth's Moon, despite the low inclination and eccentricity of Phobos's orbit.1990A&A...233..235B; Page 2351991BAICz..42..271P Page 271 Due to the effect of librations and the parallax due to the close distance of Phobos, by observing at high and low latitudes and observing as Phobos is rising and setting, the overall total coverage of Phobos's surface that is visible at one time or another from one location or another on Mars's surface is considerably higher than 50%.
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