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Lunar Habitation
Lunar habitation is any human habitation on the Moon. Lunar habitation is provided by surface habitats, possibly as part of a moonbase. History alt='' Eagle'', the first ever '' Eagle'', the first ever surface habitat and the first time people stayed on an extraterrestrial body, July 20, 1969 Lunar habitats have been designed for many different proposed moonbases. The only lunar habitats to have been erected thus far were the temporary Apollo Lunar Modules, such as ''Eagle'' of Tranquility Base, the very first. As of 2024, two programs, the US-led Artemis program and Chinese-led International Lunar Research Station aim to establish permanent surface settlements. Analysis Growth of plants in lunar regolith, in a laboratory with Apollo program regolith samples. Setting up structures on a natural body would provide ample sources of material for their construction, particularly for purposes such as shielding from cosmic radiation. The energy required to send objects fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earth-crosser Asteroid
An Earth-crosser is a near-Earth asteroid whose orbit crosses that of Earth as observed from the ecliptic pole of Earth's orbit. The known numbered Earth-crossers are listed here. Those Earth-crossers whose semi-major axes are smaller than Earth's are Aten asteroids; the remaining ones are Apollo asteroids. ''(See also the Amor asteroids.)'' An asteroid with an Earth-crossing orbit is not necessarily in danger of colliding with Earth. The orbit of an Earth-crossing asteroid may not even intersect with that of Earth. This apparent contradiction arises because many asteroids have highly inclined orbits, so although they may have a perihelion less than that of Earth, their paths can never cross. An asteroid for which there is some possibility of a collision with Earth at a future date and which is above a certain size is classified as a potentially hazardous asteroid (PHA). Specifically, an asteroid is a PHA if its Earth minimum orbital intersection distance (MOID) is <0.05 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heat Reservoir
A thermal reservoir, also thermal energy reservoir or thermal bath, is a thermodynamic system with a heat capacity so large that the temperature of the reservoir changes relatively little when a significant amount of heat is added or extracted. As a conceptual simplification, it effectively functions as an infinite pool of thermal energy at a given, constant temperature. Since it can act as an inertial source and sink of heat, it is often also referred to as a heat reservoir or heat bath. Lakes, oceans and rivers often serve as thermal reservoirs in geophysical processes, such as the weather. In atmospheric science, large air mass In meteorology, an air mass is a volume of air defined by its temperature and humidity. Air masses cover many hundreds or thousands of square miles, and adapt to the characteristics of the surface below them. They are classified according to ...es in the atmosphere often function as thermal reservoirs. Since the temperature of a thermal rese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shackleton (crater)
Shackleton is an impact crater that lies at the lunar south pole. The peaks along the crater's rim are exposed to almost continual sunlight, while the interior is perpetually in shadow. The low-temperature interior of this crater functions as a cold trap that may capture and freeze volatiles shed during comet impacts on the Moon. Measurements by the ''Lunar Prospector'' spacecraft showed higher than normal amounts of hydrogen within the crater, which may indicate the presence of water ice. The crater is named after Antarctic explorer Ernest Shackleton. Description The rotational axis of the Moon passes through Shackleton, near the rim. The crater is in diameter and deep. From the Earth, it is viewed edge-on in a region of rough, cratered terrain. It is located within the South Pole–Aitken basin on a massif. The rim is slightly raised about the surrounding surface and it has an outer rampart that has been only lightly impacted. No significant craters intersect the rim, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peak Of Eternal Light
A peak of eternal light (PEL) is a hypothetical point on the surface of an astronomical body that is always in sunlight. Such a peak must have high latitude, high elevation, and be on a body with very small axial tilt. The existence of such peaks was first postulated by Beer and Mädler in 1837. The pair said about the lunar polar mountains: "...many of these peaks have (with the exception of eclipses caused by the Earth) eternal sunshine". These polar peaks were later mentioned by Camille Flammarion in 1879, who speculated that there may exist at the poles of the Moon. PELs would be advantageous for space exploration and space colonization, colonization due to the ability of an electrical device located there to receive solar power regardless of the time of day or day of the year, and the relatively stable temperature range. Detailed lunar topography collected by the Lunar Reconnaissance Orbiter (LRO) suggests that no points on the Moon receive perpetual light during both the wint ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hectare
The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100-metre sides (1 hm2), that is, square metres (), and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is about and one hectare contains about . In 1795, when the metric system was introduced, the ''are'' was defined as 100 square metres, or one square decametre, and the hectare (" hecto-" + "are") was thus 100 ''ares'' or km2 ( square metres). When the metric system was further rationalised in 1960, resulting in the International System of Units (), the ''are'' was not included as a recognised unit. The hectare, however, remains as a non-SI unit accepted for use with the SI and whose use is "expected to continue indefinitely". Though the dekare/decare daa () and are (100 m2) are not officially "accepted for use", they are still used in some contexts. Description The hectare (), although not a unit of SI, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ionic Liquid
An ionic liquid (IL) is a salt (chemistry), salt in the liquid state at ambient conditions. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such as water and gasoline are predominantly made of electric charge, electrically neutral molecules, ionic liquids are largely made of ions. These substances are variously called liquid electrolytes, ionic melts, ionic fluids, fused salts, liquid salts, or ionic glasses. Ionic liquids have many potential applications. They are powerful solvents and can be used as electrolytes. Salts that are liquid at near-ambient temperature are important for electric battery applications, and have been considered as sealants due to their very low vapor pressure. Any salt that melts without pyrolysis, decomposing or vaporizing usually yields an ionic liquid. Sodium chloride (NaCl), for example, melts at into a liquid that consists largely of sodium cations () and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zenith Telescope
A zenith telescope is a type of telescope that is designed to point straight up at or near the zenith. They are used for precision measurement of star positions, to simplify telescope construction, or both. A classic zenith telescope, also known as a zenith sector employs a strong altazimuth mount, fitted with levelling screws. Extremely sensitive levels are attached and the telescope has an eyepiece fitted with a Micrometer (device), micrometer. They are used for the measurement of small differences of zenith distance, and used in the determination of astronomic latitude. Other types of zenith telescopes include the Monument to the Great Fire of London, which includes a central shaft meant for use as a zenith telescope. High-precision (and fixed building) zenith telescopes were also used until the early 1980s to track Earth's north pole position e.g. Earth's rotation axis position (polar motion). Since then radio astronomy, radio astronomical quasar measurements (VLBI) have also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Telescope
A radio telescope is a specialized antenna (radio), antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency portion of the electromagnetic spectrum, just as optical telescopes are used to make observations in the visible light, visible portion of the spectrum in traditional optical astronomy. Unlike optical telescopes, radio telescopes can be used in the daytime as well as at night. Since astronomical radio sources such as planets, stars, nebulas and galaxy, galaxies are very far away, the radio waves coming from them are extremely weak, so radio telescopes require very large antennas to collect enough radio energy to study them, and extremely sensitive receiving equipment. Radio telescopes are typically large Parabolic antenna, parabolic ("dish") antennas similar to those employed in tracking and communicating with satellites an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Telescope
An infrared telescope is a telescope that uses infrared light to detect celestial bodies. Infrared light is one of several types of radiation present in the electromagnetic spectrum. All celestial objects with a temperature above absolute zero emit some form of electromagnetic radiation. In order to study the universe, scientists use several different types of telescopes to detect these different types of emitted radiation in the electromagnetic spectrum. Some of these are gamma ray, x-ray, ultra-violet, regular visible light (optical), as well as infrared telescopes. Leading discoveries There were several key developments that led to the invention of the infrared telescope: * In 1800, William Herschel discovered infrared radiation. * In 1878, Samuel Pierpoint Langley created the first bolometer. This was a very sensitive instrument that could electrically detect incredibly small changes in temperature in the infrared spectrum. * Thomas Edison used an alternative technolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Seeing
In astronomy, seeing is the degradation of the real image, image of an astronomical object due to turbulence in the atmosphere of Earth that may become visible as blurring, twinkling or variable Distortion (optics), distortion. The origin of this effect is rapidly changing variations of the optical refractive index along the light path from the object to the detector. Seeing is a major limitation to the angular resolution in astronomical observations with telescopes that would otherwise be Angular resolution#The Rayleigh criterion, limited through diffraction by the size of the telescope aperture. Today, many large scientific ground-based optical telescopes include adaptive optics to overcome seeing. The strength of seeing is often characterized by the angular diameter of the long-exposure image of a star (''seeing disk'') or by the Fried parameter ''r''0. The diameter of the seeing disk is the full width at half maximum of its optical intensity. An exposure time of several tens o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epoxy
Epoxy is the family of basic components or Curing (chemistry), cured end products of epoxy Resin, resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide functional group is also collectively called ''epoxy''. The IUPAC name for an epoxide group is an oxirane. Epoxy resins may be reacted (cross-linked) either with themselves through catalytic homopolymerisation, or with a wide range of co-reactants including polyfunctional amines, acids (and acid anhydrides), phenols, alcohols and thiols (sometimes called mercaptans). These co-reactants are often referred to as hardeners or curatives, and the cross-linking reaction is commonly referred to as Curing (chemistry), curing. Reaction of polyepoxides with themselves or with polyfunctional hardeners forms a thermosetting polymer, often with favorable mechanical properties and high thermal and chemical resistance. Epoxy has a wide range of application ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
