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49-448: A 1961 New Scientist article speculating on the later-dismissed theory that the craters on the Moon might be volcanic in origin noted that "craters produced by volcanism are blessed with advantages of terrain and mineralization not found on impact craters". A crater may become a crater lake if conditions are suitable. This requires that the crater have relatively even and solid walls, and

98-408: A nuclear reactor , it has the advantage that the beam can be pulsed with relative ease. Furthermore, the energetic cost of one spallation neutron is six times lower than that of a neutron gained via nuclear fission. In contrast to nuclear fission, the spallation neutrons cannot trigger further spallation or fission processes to produce further neutrons. Therefore, there is no chain reaction, which makes

147-431: A particle accelerator may be used to produce a beam of neutrons . A particle beam consisting of protons at around 1 GeV is shot into a target consisting of mercury , tantalum , lead or another heavy metal. The target nuclei are excited and upon deexcitation, 20 to 30 neutrons are expelled per nucleus. Although this is a far more expensive way of producing neutron beams than by a chain reaction of nuclear fission in

196-447: A projectile . In planetary physics , spallation describes meteoritic impacts on a planetary surface and the effects of stellar winds and cosmic rays on planetary atmospheres and surfaces . In the context of mining or geology , spallation can refer to pieces of rock breaking off a rock face due to the internal stresses in the rock; it commonly occurs on mine shaft walls. In the context of metal oxidation, spallation refers to

245-764: A "slightly updated design, with ... a fresher, brighter feel". A dedicated "Views" section was added between news reports and in-depth features, including readers' letters, comment, and reviews on science, culture and society. Regular columnists were introduced, and columns in the culture pages. The light-hearted "Back Pages" includes the long-standing Feedback and The Last Word, puzzles, and a Q&A section. Online readership takes various forms. Overall global views of an online database of over 100,000 articles are 10.8m by 7m unique users according to Google Analytics , as of January 2019 . On social media there are 3.5m+ Twitter followers, 3.5m+ Facebook followers and 100,000+ Instagram followers as of January 2019 . Emily Wilson

294-672: A drilling rig. This phenomenon is called "cratering" in oil field slang. An example is the Darvaza gas crater near Darvaza , Turkmenistan. New Scientist New Scientist is a popular science magazine covering all aspects of science and technology. Based in London , it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organisation publishes

343-468: A function of laser fluence. Due to the non-contact application of load, this technique is very well suited to spall ultra- thin films (1 micrometre in thickness or less). It is also possible to mode convert a longitudinal stress wave into a shear stress using a pulse shaping prism and achieve shear spallation. Nuclear spallation from the impact of cosmic rays occurs naturally in Earth's atmosphere and on

392-407: A monthly Dutch-language edition. First published on 22 November 1956, New Scientist has been available in online form since 1996. Sold in retail outlets (paper edition) and on subscription (paper and/or online), the magazine covers news, features, reviews and commentary on science, technology and their implications. New Scientist also publishes speculative articles, ranging from the technical to

441-495: A pit crater chain collapse, they become troughs . In these cases, the craters may merge into a linear alignment and are commonly found along extensional structures such as fractures, fissures and graben. Pit craters usually lack an elevated rim as well as the ejecta deposits and lava flows that are associated with impact craters . Pit craters are characterized by vertical walls that are often full of fissures and vents. They usually have nearly circular openings. A subsidence crater

490-501: A source of water such as floodwaters, rain, snow, springs, or other groundwater. An impact crater is a depression in the surface of a planet , moon , or other solid body in the Solar System or elsewhere, formed by the hypervelocity impact of a smaller body. In contrast to volcanic craters , which result from explosion or internal collapse, impact craters typically have raised rims and floors that are lower in elevation than

539-442: A subscription. In the first half of 2013, the international circulation of New Scientist averaged 125,172. While this was a 4.3% reduction on the previous year's figure, it was a much smaller reduction in circulation than many mainstream magazines of similar or greater circulation. UK circulation fell by 3.2% in 2014, but stronger international sales increased the circulation to 129,585. A monthly Dutch edition of New Scientist

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588-587: A subsidence crater or collapse crater) is a depression formed by a sinking or collapse of the surface lying above a void or empty chamber, rather than by the eruption of a volcano or lava vent . Pit craters are found on Mercury , Venus , Earth , Mars , and the Moon . Pit craters are often found in a series of aligned or offset chains and in these cases, the features is called a pit crater chain. Pit crater chains are distinguished from catenae or crater chains by their origin. When adjoining walls between pits in

637-418: A tree. Some evolutionary biologists who actively oppose the intelligent design movement thought the cover was both sensationalist and damaging to the scientific community. Spallation Spallation is a process in which fragments of material ( spall ) are ejected from a body due to impact or stress. In the context of impact mechanics it describes ejection of material from a target during impact by

686-491: A type of larger depression known as a caldera . A maar is a broad, low- relief volcanic crater caused by a phreatomagmatic eruption (an explosion which occurs when groundwater comes into contact with hot lava or magma ). A maar characteristically fills with water to form a relatively shallow volcanic crater lake which may also be called a maar. These lakes may become soda lakes , many of which are associated with active tectonic and volcanic zones. An explosion crater

735-534: Is a depression from an underground (usually nuclear) explosion. Many such craters are commonly present at bomb testing areas; one notable example is the Nevada Test Site , which was historically used for nuclear weapons testing over a period of 41 years. Subsidence craters are created as the roof of the cavity caused by the explosion collapses. This causes the surface to depress into a sink (which subsidence craters are sometimes called; see sink hole ). It

784-488: Is possible for further collapse to occur from the sink into the explosion chamber. When this collapse reaches the surface, and the chamber is exposed atmospherically to the surface, it is referred to as a chimney . It is at the point that a chimney is formed through which radioactive fallout may reach the surface. At the Nevada Test Site, depths of 100 to 500 meters (330 to 1,640 ft) were used for tests. When

833-409: Is produced by an explosion near or below the surface of the ground. A crater is formed by an explosive event through the displacement and ejection of material from the ground. It is typically bowl-shaped. High-pressure gas and shock waves cause three processes responsible for the creation of the crater, these being plastic deformation of the ground, projection of material ( ejecta ) from the ground by

882-429: Is pulsed at the rate of 50 Hz, and this intense beam of protons is focused onto a target. Experiments have been done with depleted uranium targets but although these produce the most intense neutron beams, they also have the shortest lives. Generally, therefore, tantalum or tungsten targets have been used. Spallation processes in the target produce the neutrons, initially at very high energies —a good fraction of

931-444: Is used to create a compressive stress pulse in the substrate wherein it propagates and reflects as a tensile wave at the free boundary. This tensile pulse spalls/peels the thin film while propagating towards the substrate. Using theory of wave propagation in solids it is possible to extract the interface strength. The stress pulse created in this example is usually around 3 to 8 nanoseconds in duration while its magnitude varies as

980-657: The European Spallation Source ) or a combination of linac and synchrotron (e.g. ISIS neutron source ) or a cyclotron (e.g. SINQ (PSI) ) . As an example, the ISIS neutron source is based on some components of the former Nimrod synchrotron . Nimrod was uncompetitive for particle physics so it was replaced with a new synchrotron, initially using the original injectors , but which produces a highly intense pulsed beam of protons. Whereas Nimrod would produce around 2 μA at 7 GeV, ISIS produces 200 μA at 0.8 GeV. This

1029-415: The Moon , Mercury , Callisto , Ganymede and most small moons and asteroids . On other planets and moons that experience more active surface geological processes, such as Earth , Venus , Europa , Io and Titan , visible impact craters are less common because they become eroded , buried or transformed by tectonics over time. Where such processes have destroyed most of the original crater topography,

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1078-480: The Letters page. A readers' letters section discusses recent articles and discussions also take place on the website. Readers contribute observations on examples of pseudoscience to Feedback, and offer questions and answers on scientific and technical topics to Last Word. New Scientist has produced a series of books compiled from contributions to Last Word. From issue 3228 of 4 May 2019, New Scientist introduced

1127-411: The article, saying that it is "an ideas magazine—that means writing about hypotheses as well as theories". In January 2009, New Scientist ran a cover with the title " Darwin was wrong". The actual story stated that specific details of Darwin's evolution theory had been shown incorrectly, mainly the shape of phylogenetic trees of interrelated species, which should be represented as a web instead of

1176-459: The breaking off of the oxide layer from a metal. For example, the flaking off of rust from iron. In the context of anthropology , spallation is a process used to make stone tools such as arrowheads by knapping . In nuclear physics , spallation is the process in which a heavy nucleus emits numerous nucleons as a result of being hit by a high-energy particle , thus greatly reducing its atomic weight . In industrial processes and bioprocessing

1225-408: The cosmic rays were evidently formed from spallation of oxygen, nitrogen, carbon and perhaps silicon in the cosmic ray sources or during their lengthy travel here. Cosmogenic isotopes of aluminium , beryllium , chlorine , iodine and neon , formed by spallation of terrestrial elements under cosmic ray bombardment, have been detected on Earth. Nuclear spallation is one of the processes by which

1274-525: The explosion, and spallation of the ground surface. Two processes partially fill the crater back in, the immediate fall-back of ejecta, and later erosion and landslides of the crater lip and wall. The relative importance of the five processes varies, depending on the height above or depth below the ground surface at which the explosion occurs and on the composition of the ground. Differences in these characteristics will yield craters of different shapes, sizes, and other characteristics. A pit crater (also called

1323-403: The feasibility of nuclear transmutation of high level waste into less harmful substances. Besides having a neutron multiplication factor just below criticality , subcritical reactors can also produce net usable energy as the average energy expenditure per neutron produced ranges around 30 MeV (1GeV beam producing a bit over 30 neutrons in the most productive targets) while fission produces on

1372-756: The first issue included an article "Where next from Calder Hall?" on the future of nuclear power in the UK, a topic that it has covered throughout its history. In 1964, there was a regular "Science in British Industry" section with several items. Throughout most of its history, New Scientist has published cartoons as light relief and comment on the news, with contributions from regulars such as Mike Peyton and David Austin . The Grimbledon Down comic strip, by cartoonist Bill Tidy , appeared from 1970 to 1994. The Ariadne pages in New Scientist commented on

1421-458: The first page of an issue in March could be 649 instead of 1. Later issues numbered issues separately. From the beginning of 1961 " The " was dropped from the title. From 1965, the front cover was illustrated. Until the 1970s, colour was not used except on the cover. Since its first issue, New Scientist has written about the applications of science, through its coverage of technology. For example,

1470-459: The free end of the plate. This fragment known as " spall " acts as a secondary projectile with velocities that can be as high as one third of the stress wave speed on the material. This type of failure is typically an effect of high explosive squash head ( HESH ) charges. Laser induced spallation is a recent experimental technique developed to understand the adhesion of thin films with substrates . A high energy pulsed laser (typically Nd:YAG )

1519-402: The lighter side of science and technology and included contributions from David E. H. Jones , Daedalus . The fictitious inventor devised plausible but impractical and humorous inventions, often developed by the (fictitious) DREADCO corporation. Daedalus later moved to Nature . Issues of (The) New Scientist from issue 1 to the end of 1989 are free to read online; subsequent issues require

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1568-466: The loss of tubing material due to the repeated flexing of the tubing within a peristaltic pump is termed spallation. Spallation can occur when a tensile stress wave propagates through a material and can be observed in flat plate impact tests. It is caused by an internal cavitation due to stresses, which are generated by the interaction of stress waves, exceeding the local tensile strength of materials. A fragment or multiple fragments will be created on

1617-469: The magazine to Kingston Acquisitions, a group established by Sir Bernard Gray , Louise Rogers and Matthew O'Sullivan to acquire New Scientist . Kingston Acquisitions then renamed itself New Scientist Ltd. The New Scientist was subsequently sold to the Daily Mail and General Trust (DMGT) for £70 million in March 2021; DMGT guaranteed the magazine's editorial independence, and ruled out staff cuts and

1666-581: The magazine. The British monthly science magazine Science Journal , published from 1965 until 1971, was merged with New Scientist to form New Scientist and Science Journal . In 1970, the Reed Group, which became Reed Elsevier , acquired New Scientist when it merged with IPC Magazines . Reed retained the magazine when it sold most of its consumer titles in a management buyout to what is now TI Media . In April 2017 New Scientist changed ownership when RELX Group , formerly known as Reed Elsevier, sold

1715-411: The main countries where it is purchased. In the 21st century, until May 2019, New Scientist contained the following sections: Leader, News (Upfront), Technology, Opinion (interviews, point-of-view articles and letters), Features (including cover article), CultureLab (book and event reviews), Feedback (humour), The Last Word (questions and answers) and Jobs & Careers. A Tom Gauld cartoon appears on

1764-487: The makers of New Scientist , exploring the future through the world of science fiction" and fact was launched. In the same year the magazine launched a dating service, NewScientistConnect, operated by The Dating Lab. Since 2016 New Scientist has held an annual science festival in London. Styled New Scientist Live , the event has attracted high-profile scientists and science presenters. In September 2006, New Scientist

1813-415: The material above the explosion is solid rock, then a mound may be formed by broken rock that has a greater volume. This type of mound has been called "retarc", "crater" spelled backwards. When a drilling oil well encounters high-pressured gas which cannot be contained either by the weight of the drilling mud or by blow-out preventers, the resulting violent eruption can create a large crater which can swallow

1862-411: The order of 200 MeV per actinide atom that is split. Even at relatively low energy efficiency of the processes involved, net usable energy could be generated while being able to use actinides unsuitable for use in conventional reactors as "fuel". Generally the production of neutrons at a spallation source begins with a high-powered proton accelerator . The accelerator may consist of a linac only (as in

1911-409: The philosophical. New Scientist was acquired by Daily Mail and General Trust (DMGT) in March 2021. The magazine was founded in 1956 by Tom Margerison , Max Raison and Nicholas Harrison as The New Scientist , with Issue 1 on 22 November 1956, priced at one shilling (equivalent to £1.58 in 2023 ). An article in the magazine's 10th anniversary issues provides anecdotes on the founding of

1960-411: The process non-critical. Observations of cosmic ray spallation had already been made in the 1930s, but the first observations from a particle accelerator occurred in 1947, and the term "spallation" was coined by Nobelist Glenn T. Seaborg that same year. Spallation is a proposed neutron source in subcritical nuclear reactors like the upcoming research reactor MYRRHA , which is planned to investigate

2009-439: The publication of "meaningless double-talk" designed to bypass a fatal objection to Shawyer's proposed space drive, namely that it violates the law of conservation of momentum . Egan urged others to write to New Scientist and pressure the magazine to raise its standards, instead of "squandering the opportunity that the magazine's circulation and prestige provides". The editor of New Scientist , then Jeremy Webb, replied defending

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2058-475: The sharing of editorial content. In December 2021, DMGT announced that both New Scientist and the DMGT-owned daily i newspaper would be moved to a new division of the company, to be called Harmsworth Media. Originally, the cover of New Scientist listed articles in plain text. Initially, page numbering followed academic practice with sequential numbering for each quarterly volume. So, for example,

2107-459: The surfaces of bodies in space such as meteorites and the Moon . Evidence of cosmic ray spallation is seen on outer surfaces of bodies and gives a means of measuring the length of time of exposure. The composition of cosmic rays themselves may also indicate that they have suffered spallation before reaching Earth, because the proportion of light elements such as lithium, boron, and beryllium in them exceeds average cosmic abundances; these elements in

2156-487: The surrounding terrain. All lunar craters are impact craters, ranging from microscopic craters on lunar rocks returned by the Apollo program and small, simple, bowl-shaped depressions in the lunar regolith to large, complex, multi-ringed impact basins . Meteor Crater is a well-known example of a small impact crater on Earth. Impact craters are the dominant geographic features on many solid Solar System objects including

2205-414: The terms impact structure or astrobleme are more commonly used. In early literature, before the significance of impact cratering was widely recognised, the terms cryptoexplosion or cryptovolcanic structure were often used to describe what are now recognised as impact-related features on Earth. A volcanic crater is a bowl-shaped depression in the ground caused by volcanic activity, usually located above

2254-472: The volcano's vent. During volcanic eruptions , molten magma and volcanic gases rise from an underground magma chamber , through a conduit, until they reach the crater's vent, from where the gases escape into the atmosphere and the magma is erupted as lava . A volcanic crater can be of large dimensions, and sometimes of great depth. During certain types of explosive eruptions , a volcano's magma chamber may empty enough for an area above it to subside, forming

2303-414: Was appointed editor-in-chief in 2018. New Scientist has published books derived from its content, many of which are selected questions and answers from the "Last Word" section of the magazine and website: Other books published by New Scientist include: New Scientist has also worked with other publishers to produce books based on the magazine's content: In 2012 Arc , "a new digital quarterly from

2352-457: Was criticised by science fiction writer Greg Egan , who wrote that "a sensationalist bent and a lack of basic knowledge by its writers" was making the magazine's coverage sufficiently unreliable "to constitute a real threat to the public understanding of science". In particular, Egan found himself "gobsmacked by the level of scientific illiteracy" in the magazine's coverage of Roger Shawyer's " electromagnetic drive ", where New Scientist allowed

2401-580: Was launched in June 2015. It replaced the former Natuurwetenschap & Techniek  [ nl ] (NWT) magazine, adopting its staff and subscribers. The editorially independent magazine is published by Veen Media. It contains mainly translations of articles in the English-language edition, but also its own articles. These are typically focused on research in the Netherlands and Belgium,

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