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Lunar X
The Lunar X (also known as the Werner X) is a clair-obscur effect in which light and shadow creates the appearance of a letter 'X' on the rim of the Blanchinus, La Caille and Purbach craters. The X is visible only for a few hours before the first quarter, slightly below the lunar terminator A terminator or twilight zone is a moving line that divides the daylit side and the dark night side of a planetary body. The terminator is defined as the locus of points on a planet or moon where the line through the center of its parent star is .... Near to the X, the Lunar V is also visible, formed by Ukert crater and several other small craters. References External links *LPOD articles: ** ** ** *APOD articles: ** ** - also includes the Lunar V Moon {{Moon-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clair-obscur
Chiaroscuro ( , ; ), in art, is the use of strong contrast (vision), contrasts between light and dark, usually bold contrasts affecting a whole composition. It is also a technical term used by artists and art historians for the use of contrasts of light to achieve a sense of volume in modelling three-dimensional objects and figures. Similar effects in cinema, and black and white and low-key photography, are also called chiaroscuro. Further specialized uses of the term include chiaroscuro woodcut for coloured woodcuts printed with different blocks, each using a different coloured ink; and chiaroscuro drawing for drawings on coloured paper in a dark medium with white highlighting. Chiaroscuro is one of the canonical painting modes of the Renaissance (alongside cangiante, sfumato and unione) (see also Renaissance art). Artists known for using the technique include Leonardo da Vinci, Caravaggio Rembrandt, Johannes Vermeer, Vermeer and Francisco Goya, Goya, and Georges de La Tour. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blanchinus (crater)
Blanchinus is a lunar impact crater that is situated in the rugged south-central highlands of the Moon. The crater is named after Italian astronomer Giovanni Bianchini whose Latinized name is Blanchinus. Adjacent to the south of Blanchinus is the crater Werner, and La Caille Abbé Nicolas-Louis de Lacaille (; 15 March 171321 March 1762), formerly sometimes spelled de la Caille, was a French astronomer and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the Cape of Goo ... is attached to the northwest rim. West of the crater is the prominent formation Purbach. The outer rim of Blanchinus has been significantly degraded by subsequent impacts, leaving an irregular, notched exterior ring of rugged hills and ridges. The inner floor, in contrast, is nearly flat and free of significant impacts. Only a few tiny craterlets mark the interior surface, with Blanchinus M located near the midpoint and the remainder lie near the southwest rim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Caille (crater)
La Caille is a lunar impact crater located in the rugged south-central highlands of the Moon. It was named after the French astronomer Nicolas-Louis de Lacaille. It is located to the northeast of the crater Purbach. Nearly attached to the southeast rim are the remains of Blanchinus, and the two are separated by a rugged stretch of terrain. To the northeast is Delaunay, a formation split in half by a ridge. The floor of La Caille has been flooded in the past by lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or un ..., and the surface is relatively smooth and flat with no central rise. Only a few tiny craterlets along the north and northwest edges disrupt the surface. Ray material lies across the central and southern parts of the floor, most likely from Tycho to the southwest. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purbach (crater)
Purbach is a large lunar impact crater located in the rugged southern highlands of the Moon. The distorted crater Regiomontanus is attached to the southern rim. To the northwest is Thebit and just to the northeast lies La Caille. Description The outer wall of Purbach is heavily worn, with the most intact section being along the east and northeast sides. The shared rim between Purbach and Regiomontanus is incised and rugged. The wall is distorted along the western edge, giving the appearance of a double rim, with the second rim distended towards the west. The northern wall is almost completely destroyed, and somewhat irregular Purbach G lies across the northwest rim. The crater floor is relatively smooth in the eastern half, with a low series of ridges and a partial ghost crater outline just to the west of the crater midpoint. If the crater possessed a central peak, it has either been removed or forms part of the ridges to the west. For a few hours before the first quarter, the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambridge University Press
Cambridge University Press is the university press of the University of Cambridge. Granted letters patent by Henry VIII of England, King Henry VIII in 1534, it is the oldest university press A university press is an academic publishing house specializing in monographs and scholarly journals. Most are nonprofit organizations and an integral component of a large research university. They publish work that has been reviewed by schola ... in the world. It is also the King's Printer. Cambridge University Press is a department of the University of Cambridge and is both an academic and educational publisher. It became part of Cambridge University Press & Assessment, following a merger with Cambridge Assessment in 2021. With a global sales presence, publishing hubs, and offices in more than 40 Country, countries, it publishes over 50,000 titles by authors from over 100 countries. Its publishing includes more than 380 academic journals, monographs, reference works, school and uni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lunar Terminator
A terminator or twilight zone is a moving line that divides the daylit side and the dark night side of a planetary body. The terminator is defined as the locus of points on a planet or moon where the line through the center of its parent star is tangent. An observer on the terminator of such an orbiting body with an atmosphere would experience twilight due to light scattering by particles in the gaseous layer. Earth's terminator On Earth, the terminator is a circle with a diameter that is approximately that of Earth. The terminator passes through any point on Earth's surface twice a day, at sunrise and at sunset, apart from polar regions where this only occurs when the point is not experiencing midnight sun or polar night. The circle separates the portion of Earth experiencing daylight from that experiencing darkness (night). While a little over one half of Earth is illuminated at any point in time (with exceptions during eclipses), the terminator path varies by time of day due ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ukert (crater)
Ukert is a lunar impact crater that lies on a strip of rugged ground between Mare Vaporum to the north and Sinus Medii in the south. It was named after German historian Friedrich August Ukert. It is located to the north-northwest of the crater Triesnecker and northeast of the crater pair of Pallas Pallas may refer to: Astronomy * 2 Pallas asteroid ** Pallas family, a group of asteroids that includes 2 Pallas * Pallas (crater), a crater on Earth's moon Mythology * Pallas (Giant), a son of Uranus and Gaia, killed and flayed by Athena * Pa ... and Murchison. The outer rim of this crater is not quite circular, with outward bulges to the north and the east. The interior floor is irregular in places, with a central ridge running from crater midpoint down to the southern wall. There is a tiny craterlet along the northern rim, but otherwise the crater contains no impacts of note. Satellite craters By convention these features are identified on lunar maps by placing the letter o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Half Waxing Moon With Inset Closeup Of Point X
One half ( : halves) is the irreducible fraction resulting from dividing one by two or the fraction resulting from dividing any number by its double. Multiplication by one half is equivalent to division by two, or "halving"; conversely, division by one half is equivalent to multiplication by two, or "doubling". One half often appears in mathematical equations, recipes, measurements, etc. Half can also be said to be one part of something divided into two equal parts. For instance, the area ''S'' of a triangle is computed. :''S'' = × perpendicular height. One half also figures in the formula for calculating figurate numbers, such as triangular numbers and pentagonal numbers: : \frac and in the formula for computing magic constants for magic squares : M_2(n) = \frac \left(n^ + 1\right) The Riemann hypothesis states that every nontrivial complex root of the Riemann zeta function has a real part equal to . One half has two different decimal expansions, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
