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Mab (moon)

Mab is a closer moon to the planet Uranus. It was found by Mark R. Showalter and Jack J. Lissauer in 2003 using the Hubble Space Telescope. It was named after Queen Mab, a fairy queen from English folklore who is noted in William Shakespeares pla ...

                                               

Macrosociology

Macro-sociology is a way of looking at the world of people in a broad way. It studies mass of many peoples. It is about "concerned with human societies". Macrosociology is considered one of the main foundations of sociology. In sociology there ar ...

                                               

Madness

Madness is a word that can have different meanings: Up to about the 19th century someone who acted strangely, or outside the socially accepted norms was called mad or insane. This could range from having bizarre ideas to someone having delusions ...

                                               

Magellan (spacecraft)

The Magellan spacecraft, also called the Venus Radar Mapper, was a NASA spaceprobe designed to explore the Venus planet. It was launched on May 4, 1989, and reached Venus on August 10, 1990. It was in orbit around Venus for four years making deta ...

                                               

Magnetic permeability

Magnetic permeability is a way to explain how easy or hard it is for a substance to support a magnetic field. It is usually represented in science by the Greek letter µ.

                                               

Magnetostatics

Magnetostatics is the study of magnetic fields in systems where the electric currents are steady. Magnetostatics is widely used in magnetic storage devices such as in computer memory. Magnetostatic focussing can be got by a permanent magnet or by ...

                                               

Makemake (dwarf planet)

Makemake is a dwarf planet. It was discovered on March 31, 2005 by astronomers Michael E. Brown, Chad Trujillo and David Rabinowitz. It was announced as a dwarf planet on June 11, 2008, and the discovery of a moon was announced on April 26, 2016. ...

                                               

Malleability

Malleability is a substances ability to deform under pressure. If malleable, a material may be flattened into thin sheets by hammering or rolling. Malleable materials can be flattened into metal leaf. One well-known type of metal leaf is gold lea ...

                                               

Man and the Biosphere Programme

The Man and the Biosphere Programme is a division of UNESCO that tries to improve and encourage conservation and sustainability around the world. It was created in 1971. Its main focus is a network of biosphere reserves. The programme acts as a k ...

                                               

Map projection

A map projection is a way of showing the surface of a three-dimensional sphere on a flat surface. Such projections are necessary to create maps. The problem with projections is that they change the surface in some way; this is called distortion. ...

                                               

Marble

For the toy, see marbles Marble is a metamorphic rock that developed from limestone. Most of the material is calcite and dolomite. It is often used for sculpture, as a building material, and for many other purposes. The word marble is also used f ...

                                               

Mare Tranquillitatis

Mare Tranquillitatis is a large area on the visible side of the Moon. It is also called the Sea of Tranquillity. It is called a sea because ancient astronomers looked at the Moon and thought they saw seas and oceans on the Moon. Now we know that ...

                                               

Mars Climate Orbiter

The Mars Climate Orbiter was a space probe. It was launched by NASA on 11 December 1998 to study the Martian climate and Martian atmosphere. However, on 23 September 1999, communication with the spacecraft was lost, when the spacecraft was about ...

                                               

Marsh

In geography, a marsh is a type of wetland. It has grasses, rushes, reeds, typhas, sedges, and other herbaceous plants in a context of shallow water. A marsh is different from a swamp, which has a greater proportion of open water surface, which i ...

                                               

MaS

A MaS or Mass is an old unit of measurement of liquid. Literally translated, it means mass. It is equal to 1.069 litre. Today, it is only used for measuring quantities of beer. Beer is usually served as 0.2 or 0.3 l or as 0.5 l, but at some occas ...

                                               

Mass spectrum

A mass spectrum is an intensity versus m/z plot that represents a chemical analysis. The mass spectrum of a sample is a pattern representing the distribution of ions by mass in a sample. It is a histogram usually made using an instrument called a ...

                                               

Material fracture

A fracture is the separation of a body into more than one piece under the action of stress. The word fracture is often applied to bones of living creatures or to crystals or crystalline materials, such as gemstones or metal. Sometimes, fractures ...

                                               

Material property

In science, a property is anything that describes a material or substance. It is a characteristic of that material. For example, how hard the material is, its colour, or its shape. Elasticity is a property of rubber; in other words: rubber is ela ...

                                               

May 2021 lunar eclipse

A total lunar eclipse will take place on 26 May 2021. It will be the first total lunar eclipse since the January 2019 lunar eclipse. It will be visible in areas of southeast Asia, all of Australia, all of Oceania, most of Alaska and Canada, all o ...

                                               

Mean anomaly

In the study of orbital dynamics the mean anomaly of an orbiting body is the angle the body would have traveled about the center of the orbits auxiliary circle. Unlike other measures of anomaly, the mean anomaly grows linearly with time. Because ...

                                               

Mechanical wave

A mechanical wave requires a medium. Sound waves, waves in a Slinky, and pressure waves are all examples of this phenomenon. Sound waves need a physical medium in order to exist; the Slinky waves need the Slinky, and the waves in the ocean need t ...

                                               

Medical laboratory

A medical laboratory or clinical laboratory is a laboratory where tests are usually done on laboratory specimens. This is to get information about the health of a patient. Labs perform tests on tissue, blood and other body fluids. Medical labs an ...

                                               

Megaclite (moon)

Megaclite or Jupiter XIX, is a moon of Jupiter. It was found by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2000, and given the designation S/2000 J 8. Megaclite is about 5.4 kilometres in diameter, and orbits ...

                                               

Melbourne Observatory

The Melbourne Observatory, in Melbourne, Victoria, Australia, was built in 1861. It replaced an earlier observatory at Williamstown. The Melbourne Observatory is now part of Melbournes Royal Botanic Gardens. The observatory had an important role ...

                                               

Melnick 34

BAT99-116 is a binary Wolf–Rayet star near R136 in the 30 Doradus complex in the Large Magellanic Cloud. Both parts are amongst the most massive and luminous stars known. It has a spectral type of WN5h and the most massive binary system with x-ra ...

                                               

Melting

Melting is the process of changing something from a solid into a liquid. It is the opposite of freezing. The temperature at which something begins to melt is called its melting point. When an object is heated, the objects particles begin to move ...

                                               

Membrane

A membrane is a thin soft layer of material. A membrane separates two things. In biology a membrane can mean two things: a tissue membrane or the membranes of a cell. The membranes of cells are very small, while tissue membranes are larger.

                                               

Memory

Memory is the personal record of past experiences. It is the brains ability to store information to use later. The Greeks considered memory as the mother of Muses, for without her there would be no art and no science. Memory is studied in science ...

                                               

Mercury-vapor lamp

A mercury-vapor lamp is a kind of gas discharge lamp. It makes light from mercury. The mercury atoms release ultraviolet and visible light. In some bulbs, the ultraviolet light shines on phosphors which make white light from it, although not all ...

                                               

Meridian

A meridian is an imaginary line of longitude drawn along the surface of the earth from the North Pole to the South Pole. Geographers today measure these lines from what they call the Prime Meridian. It is the line of longitude that goes through t ...

                                               

Mesoarchaean

The Mesoarchaean is the third geological era in the Archaean eon. It began 3.2 billion years ago, and ended 2.8 billion years ago. Before the Mesoarchaean era was the Palaeoarchaean era. After the Mesoarchaean era was the Neoarchaean. Fossils fro ...

                                               

Mesoproterozoic

The Mesoproterozoic is a geologic era which lasted from 1.600 million years ago to 1.000 mya. The major events of this era are: the breakup of the Columbia supercontinent ~1.500 mya; the evolution of sexual reproduction. the assembly of the Rodin ...

                                               

Messier 15

Messier 15 is a globular cluster in the constellation of Pegasus. This globular cluster was discovered by Jean-Dominique Maraldi in 1746. M15 is about 33.600 lightyears from Earth, and 175 lightyears in diameter. It has more than 100.000 stars, 1 ...

                                               

Messier 38

Messier 38 or M38, also known as NGC 1912, is an open cluster of stars in the constellation of Auriga. It is about 1.066 kpc away from Earth.

                                               

Messier 52

Messier 52 or M52 is also known as NGC 7654. It is an open cluster of stars in the northern constellation of Cassiopeia. It was discovered by Charles Messier on September 7, 1774. M52 can be seen from Earth with binoculars.

                                               

Messier 7

Messier 7, also known as NGC 6475 or the Ptolemy cluster, is an open star cluster in the constellation of Scorpius. It is about 980 light-years away from Earth.

                                               

Messier 74

Messier 74, also known as NGC 628 and Phantom Galaxy is a spiral galaxy in the constellation of Pisces. It is about 32 million light-years away from Earth.

                                               

Methanol

Methanol is the simplest alcohol: CH 3 OH. It has similarities to ethanol, but it is toxic. The toxicity takes hours though, so antidotes can prevent the damage such as permanent blindness, death. It is used as fuel additive, solvent, and in the ...

                                               

Methone (moon)

Methone is a small moon of Saturn. It was discovered by the Cassini Imaging Science Team in 2004, the same time as a close-by moon, Pallene. It is only about 3 km in diameter.

                                               

Mexican Academy of Sciences

The Mexican Academy of Sciences is a non-profit organization made-up of over 1.800 Mexican scientists. It is in Mexico City.

                                               

Mica

The mica group of minerals are aluminosilicates with various metals. They split into fine sheets, which puts them in the phyllosilicate group of silicate minerals. Mica includes several closely related materials having perfect basal cleavage. All ...

                                               

Micro black hole

Micro black holes are very small black holes. Because they are small, they may shrink and disappear due to Hawking radiation. They may exist in nature as primordial black holes.

                                               

Micrograph

Micrographs are photographs taken through microscopes to show magnified versions of items. They are used for forensic engineering and forensic science to record trace evidence. Micrographs are also used for scanning electron microscopy so the sam ...

                                               

Micrometre

A micrometre is a unit of length in the SI measurement system. It can also be called a micron. It is one millionth of a metre. A micrometre is often used as a measurement for small things like bacteria. Like the Angstrom it is used for radiation ...

                                               

Microsleep

Microsleep is a very short sleep that occurs when people are awake. It can last from under a second to about 30 seconds. It may happen as a result of sleep deprivation, fatigue, sleep apnea, narcolepsy, or hypersomnia. Microsleeps can occur at an ...

                                               

Midnight sun

Midnight sun is a phenomenon that exists north of the Arctic Circle and south of the Antarctic Circle. It means that the sun, on parts of the year, is visible the whole night long. The sun above the horizon at midnight in the arctic or Antarctic ...

                                               

Mifepristone

Mifepristone is a synthetic steroid that is used as a drug. It can be used to cause a medical abortion in the first two months of pregnancy. It can also be used as an emergency contraceptive. It is often known as RU-486, the name it had in early ...

                                               

Mindset

A mindset is a state that usually a majority of people would have in a particular time or occasion. It is formed from things that people are convinced about. It is like a collected norm. Mindset can also be about how people see their abilities. I ...

                                               

Mineralogy

Mineralogy is the study of minerals. Minerals are things that make rocks. There are many different types of minerals. Some are hard, like diamonds. Some are soft, like talc. Some are metal, like gold or silver. Minerals are put into special group ...

                                               

Minmi

Minmi is a genus of small ankylosaurian dinosaur that lived during the Lower Cretaceous of Australia, about 119 to 113 million years ago. A recent cladistic analysis suggests that Minmi is the most basal known ankylosaur. That does not mean it wa ...