Parts of many craters, particularly the bottoms of many polar craters, [104] are permanently shadowed, these " craters of eternal darkness" have extremely low temperatures. The Lunar Reconnaissance Orbiter measured the lowest summer temperatures in craters at the southern pole at 35K (−238°C; −397°F) [105] and just 26K (−247°C; −413°F) close to the winter solstice in the north polar crater Hermite. This is the coldest temperature in the Solar System ever measured by a spacecraft, colder even than the surface of Pluto. [103] The Earth and the Moon form the Earth-Moon satellite system with a shared center of mass, or barycenter. This barycenter is 1,700km (1,100mi) (about a quarter of Earth's radius) beneath the Earth's surface.

The Almost Moon by Alice Sebold | Waterstones The Almost Moon by Alice Sebold | Waterstones

The moon is whole all the time, but we can’t always see it. What we see is an almost moon or a not-quite moon. The rest is hiding just out of view, but there’s only one moon, so we follow it in the sky. We plan our lives based on its rhythms and tides.”

Stay Connected

The usual English proper name for Earth's natural satellite is simply Moon, with a capital M. [20] [21] The noun moon is derived from Old English mōna, which (like all its Germanic cognates) stems from Proto-Germanic *mēnōn, [22] which in turn comes from Proto-Indo-European *mēnsis "month" [23] (from earlier *mēnōt, genitive *mēneses) which may be related to the verb "measure" (of time). [24] The most commonly known effect of tidal forces are elevated sea levels called ocean tides. [171] While the Moon exerts most of the tidal forces, the Sun also exerts tidal forces and therefore contributes to the tides as much as 40% of the Moon's tidal force; producing in interplay the spring and neap tides. [171] As the Moon travels around Earth, different parts of it are lit up by the Sun. These changes in the Moon's appearance from our view on Earth are called moon phases. This graphic shows all eight moon phases we see as the Moon makes a complete orbit of Earth about every four weeks. Credit: NASA/JPL-Caltech Is there actually a “dark side" of the Moon? The Moon was volcanically active until 1.2billion years ago, which laid down the prominent lunar maria. Most of the mare basalts erupted during the Imbrian period, 3.3–3.7billion years ago, though some are as young as 1.2billion years [62] and some as old as 4.2billion years. [63] There are differing explanations for the eruption of mare basalts, particularly their uneven occurrence which mainly appear on the near-side. Causes of the distribution of the lunar highlands on the far side are also not well understood. Topological measurements show the near side crust is thinner than the far side. One possible scenario then is that large impacts on the near side may have made it easier for lava to flow onto the surface. [64] Physical characteristics Scientists believe that the Moon formed early in the solar system’s history after Earth and an object about the size of Mars smashed into each other. The impact sent chunks of Earth and the impactor into space that were pulled together by gravity, creating the Moon. How do we study the Moon?

Moon: NASA Science Overview | Composition – Moon: NASA Science

The very thin atmosphere, known as an exosphere, contains helium, argon, neon, ammonia, methane and carbon dioxide. It also contains sodium and potassium, which are not usually found as gases in the atmospheres of Earth, Venus or Mars. There are still many questions left to answer about the Moon. And the most exciting days of lunar activity may still lie ahead as NASA sends humans on the next missions to the Moon and eventually on to Mars! For more information visit: To take the tops off all the houses and mingle our miseries was too simple a solution, I knew. Houses had windows with shades. Yards had gates and fences. There were carefully planned out sidewalks and roads, and these were the paths that, if you chose to go into someone else's reality, you had to be willing to walk. There were no shortcuts.” Exhilarating, unforgettable ... This is a remarkable novel in which every word is vital, each nuance felt ... Candid, gut-wrenching, at times horribly funny and often beautifully touching ... The genius which guides The Almost Moon is its absolute, horrible, multiple truths; its staggering clarity' Eileen Battersby, Irish Times

Main articles: Selenography, Lunar terrane, List of lunar features, and List of quadrangles on the Moon Apollo 17 astronaut Harrison H. Schmitt next to a large Moon boulder The English adjective pertaining to the Moon is "lunar", derived from the Latin word for the Moon, lūna. Selenian / s ə l iː n i ə n/ [28] is an adjective used to describe the Moon as a world, rather than as a celestial object, [29] but its use is rare. It is derived from σελήνη selēnē, the Greek word for the Moon, and its cognate selenic was originally a rare synonym [30] but now nearly always refers to the chemical element selenium. [31] The element name selenium and the prefix seleno- (as in selenography, the study of the physical features of the Moon) come from this Greek word. [32] [33] The Greek goddess of the wilderness and the hunt, Artemis, equated with the Roman Diana, one of whose symbols was the Moon and who was often regarded as the goddess of the Moon, was also called Cynthia, from her legendary birthplace on Mount Cynthus. [34] These names – Luna, Cynthia and Selene – are reflected in technical terms for lunar orbits such as apolune, pericynthion and selenocentric. The Moon is by size and mass the fifth largest natural satellite of the Solar System, categorizeable as one of its planetary-mass moons, making it a satellite planet under the geophysical definitions of the term. [18] It is smaller than Mercury and considerably larger than the largest dwarf planet of the Solar System, Pluto. While the minor-planet moon Charon of the Pluto-Charon system is larger relative to Pluto, [f] [66] the Moon is the largest natural satellite of the Solar System relative to their primary planets. [g] The impact would have released enough energy to liquefy both the ejecta and the Earth's crust, forming a magma ocean. The liquefied ejecta could have then re-accreted into the Earth–Moon system. [54] [55] The newly formed Moon would have had its own lunar magma ocean; its depth is estimated from about 500km (300 miles) to 1,737km (1,079 miles). [54]

The Almost Moon by Alice Sebold | Goodreads

Waning Gibbous: The waning gibbous phase is between a full moon and a half moon. Waning means it is getting smaller.

The prevailing theory is that the Earth–Moon system formed after a giant impact of a Mars-sized body (named Theia) with the proto-Earth. The oblique impact blasted material into orbit about the Earth and the material accreted and formed the Moon [44] [45] just beyond the Earth's Roche limit of ~ 2.56 R 🜨. [46]