Salisbury Plain

Salisbury Plain is a chalk plateau in the south western part of central southern England covering . It is part of a system of chalk downlands throughout eastern and southern England formed by the rocks of the Chalk Group and largely lies within the county of Wiltshire, but stretches into Berkshire, Hampshire and a small part of Somerset.
The plain is famous for its rich archaeology, including Stonehenge, one of England's best known landmarks. Large areas are given over to military training and thus the sparsely populated plain is the biggest remaining area of calcareous grassland in northwest Europe. Additionally the plain has arable land, and a few small areas of beech trees and coniferous woodland. Its highest point is Easton Hill.
Physical geography.
The boundaries of Salisbury Plain have never been truly defined, and there is some difference of opinion as to its exact area. The river valleys surrounding it, and other downs and plains beyond them loosely define its boundaries. To the north the scarp of the downs overlooks the Vale of Pewsey, and to the northwest the Bristol Avon. The River Wylye runs along the southwest, and the Bourne runs to the east. The Hampshire Avon runs through the eastern half of the plain, and to the south the plain peters out as the river valleys close together before meeting at Salisbury. From here the Avon continues south to the English Channel at Christchurch. The Hampshire Downs and the Berkshire Downs are chalk downland to the east and north of Salisbury Plain, and the Dorset Downs and Cranborne Chase are to the southwest. In the west and north west the geology is mainly the clays and limestones of the Blackmore Vale, Avon Vale and Vale of Wardour. The Mendip Hills rise to the west of Salisbury Plain, and the Cotswolds to the north west.
Amesbury is considered the largest settlement on the plain, though there are a number of small villages, such as Tilshead, Chitterne and Shrewton in the middle of the plain, as well as various hamlets and army camps. The A303 road runs through the southern area of the plain, while the A345 and the A360 cut across the centre.
History.
Salisbury Plain is famous for its history and archaeology. In the Neolithic period, Stone Age people began to settle on the plain, most likely centred around the causewayed enclosure of Robin Hood's Ball. Large long barrows such as White Barrow and other earthworks were built across the plain. By 2500 BC areas around Durrington Walls and Stonehenge had become a focus for building, and the southern part of the plain continued to be settled into the Bronze Age.
Around 600 BC, Iron Age hillforts came to be constructed around the boundaries of the plain, including Scratchbury Camp and Battlesbury Camp to the southwest, Bratton Camp to the northwest, Casterley Camp to the north, Yarnbury and Vespasian's Camp to the south, and Sidbury Hill to the east.
Roman roads are visible features, probably serving a settlement near Old Sarum. Villas are sparse, however, and Anglo-Saxon place names suggest that the plain was mostly a grain-producing imperial estate.
In the 6th century, Anglo-Saxon incomers built planned settlements in the valleys surrounded by strip lynchets, with the downland left as sheep pasture. To the south is the city of Salisbury, whose 13th and 14th century cathedral is famous for having the tallest spire in the country, and the building was, for many centuries, the tallest building in Britain. The cathedral is evidence of the prosperity the wool and cloth trade brought to the area. In the mid-19th century the wool and cloth industry began to decline, leading to a decline in the population and change in land use from sheep farming to agriculture and military use. Wiltshire became one of the poorest counties in England during this period of decline.
There are a number of chalk carvings on the plain, of which the most famous is the Westbury White Horse. The Kennet and Avon Canal was constructed to the north of the plain, through the Vale of Pewsey.
In September 1896, George Kemp and Guglielmo Marconi experimented with wireless telegraphy on Salisbury Plain, and achieved good results over a distance of .
Military use.
The military training area covers roughly half of the plain. The army first conducted exercises on the plain in 1898. From that time, the Ministry of Defence bought up large areas of land until the Second World War. The MoD now own of land, making it the largest military training area in the United Kingdom. Much of this land is let to farmers or grazed under licence, while around (12,000 ha) are used for live firing, where public access is greatly restricted or permanently closed. The land and facilities are managed by the MoD's Defence Infrastructure Organisation.
The largest camps and barracks are at Larkhill, Bulford, Tidworth, Trenchard Lines (Upavon) and Waterloo Lines (Warminster). Copehill Down is an urban warfare training site. Several installations have been built and since removed, including a railway line and aerodrome that were constructed next to Stonehenge. A grass aerodrome at Netheravon was used by the RAF until 1963, then by the Army Air Corps until 2012, and now as a tri-service installation.
The Royal School of Artillery has been based at Larkhill since 1915, and live firing is conducted on the plain for approximately 340 days of each year. Military personnel from the UK and around the world spend some 600,000-man days on the plain every year.
In 1943, the village of Imber and the hamlet of Hinton Parva were evacuated to allow training for Operation Overlord to be conducted. Whilst the inhabitants of Hinton Parva were allowed to return at the end of hostilities, Imber village has remained closed, except for an annual church service and some bank holidays. Roads in the Imber area are also closed, as they lie within the Imber Range live firing area; it is possible to walk all of the perimeter of the range on public footpaths.
The training area is close to other military facilities including the Defence Science and Technology Laboratory at Porton Down (much of whose work is secret), Boscombe Down airfield and Middle Wallop Army Air Corps Base in Hampshire, where pilots train on the Westland Apache.
20,000 hectares are designated Sites of Special Scientific Interest and Special Areas of Conservation, and the entire SP is a Special Protection Area for birds.
BFBS Radio broadcasts from studios on Marlborough Road, Bulford, on DAB, FM and satellite channels.
Ecology.
Because of the large training areas inaccessible to the public, the plain is a wildlife haven, and home to two national nature reserves, but there is concern that the low level of grazing on the plain could allow scrub to encroach on the grassland. The plain supports the largest known expanse of unimproved chalk downland in north west Europe, and represents 41% of Britain's remaining area of this wildlife habitat. The plain supports 13 species of nationally rare and scarce plants, 67 species of rare and scarce invertebrates and forms a site of international importance for birds. In addition to chalk downland, the plain supports scrub and woodland habitats, temporary and permanent pools and the River Bourne.
Vegetation.
A diversity of soil types, slope, aspect and past and present land-use has given rise to various grassland communities. Historical evidence suggests that large areas of grassland are of great antiquity, and areas which were cultivated at the beginning of the 20th century have experienced nearly 100 years of chalk grassland re-colonisation. Parts of East Salisbury Plain and the periphery of Central and West comprise areas of grassland currently managed for grazing pasture and hay-cutting, whilst the middle of Centre and West are ungrazed. A large proportion of Salisbury Plain supports upright brome ("Bromus erectus") species-rich grassland, within which a continuous floristic variation is seen. A widespread type on the plain is characterised by an abundance of red fescue ("Festuca rubra"), crested hair-grass ("Koeleria macrantha"), salad burnet ("Sanguisorba minor"), lady's bedstraw ("Galium verum"), rough hawkbit ("Leontodon hispidus"), common rock-rose ("Helianthemum nummularium") and dropwort ("Filipendula vulgaris"). The high constancy of this last species is a distinctive feature of the upright brome grasslands on Salisbury Plain and is otherwise only known from one other site in Hampshire. Where upright brome is less dominating, plants such as small scabiosa ("Scabiosa columbaria"), clustered bellflower ("Campanula glomerata"), dyer's greenweed ("Genista tinctoria"), kidney vetch ("Anthyllis vulneraria"), sainfoin ("Onobrychis viciifolia") and horseshoe vetch ("Hippocrepis comosa") are characteristic associates.
The rare and notable plants which occur here include burnt-tip orchid ("Neotinea ustulata"), slender bedstraw ("Galium pumilum"), field fleawort ("Senecio integrifolius") and the nationally scarce British endemic early gentian ("Gentianella anglica"). Particularly associated with long established turf on thin rendzina soils, and rabbit-grazed areas of the eastern and central ranges, are low-growing perennials including squinancy-wort ("Asperula cynanchica"), chalk milkwort ("Polygala calcarea"), dwarf thistle ("Cirsium acaule"), wild thyme ("Thymus praecox"), the nationally scarce bastard toadflax ("Thesium humifusum") and purple milk-vetch ("Astragalus danicus") in its most southerly British station.
Devil's-bit scabious ("Succisa pratensis"), saw-wort ("Serratula tinctoria") and betony ("Stachys officinalis") are all abundant and exemplify the oceanic character of the chalk grassland on the plain, a feature which is confined to South West England. Similarly restricted is a community in which dwarf sedge "Carex humilis" forms a conspicuous component. This type of grassland has its stronghold in Wiltshire and occurs on the less disturbed areas of the central ranges. Herb diversity is generally lower in the tall, upright brome-dominated swards, but wild parsnip ("Pastinaca sativa"), hogweed ("Heracleum sphondylium") and greater knapweed ("Centaurea scabiosa") are characteristic. Parasitic on the latter species is knapweed broomrape ("Orobanche elatior"), occurring in greater quantity on the plain than anywhere else in Britain. False-oat grass ("Arrhenatherum elatius") grassland is also widespread, but is particularly a feature of the western ranges, often indicating areas of past cultivation.
On anthills, and in the more disturbed turf that is especially a feature of the impact area, mouse-ear hawkweed ("Hieracium pilosella") is abundant together with sheep's fescue ("Festuca ovina") and wild thyme. Annuals are also characteristic of this habitat, including common whitlowgrass ("Erophila verna"), rue-leaved saxifrage ("Saxifraga tridactylites",) hairy rock-cress ("Arabis hirsuta") and the nationally scarce dwarf mouse-ear ("Cerastium pumilum") and fine-leaved sandwort ("Minuartia hybrida"). A very local community characterised by a lichen-rich turf ("Cladonia" species) and the broom moss ("Dicranum scoparium") is found in some stabilised missile-impaction craters on the central ranges. This vegetation type is found elsewhere only on Porton Down SSSI and on the Brecklands.
Small areas of chalk-heath vegetation occur on superficial clay-with-flints deposits. Here chalk-loving plants such as salad burnet ("Sanguisorba minor") and dropwort co-exist with plants typical of acid soils, including gorse ("Ulex europaeus"), heather ("Calluna vulgaris") and the uncommon annual knawel ("Scleranthus annuus"). Two Red Data Book (RDB) plants occur on the plain. The largest population in Britain of tuberous thistle ("Cirsium tuberosum") occurs on the western ranges and is notable for the low incidence of hybridisation with dwarf thistle, a contributory cause of its decline in other localities. Meadow clary ("Salvia pratensis") persists as a small colony in tall upright brome grassland.
Salisbury Plain supports a diverse bryophyte flora with seven nationally scarce species which have seen a general decline in other chalk grassland sites, including "Barbula acuta", "Phascum curvicolle", "Pleurochaete squarrosa", "Thuidium abietinum" and "Weissia sterilis".
Although there is some scrub development on the plain, it is remarkable that large expanses of the chalk grassland remain open with very little invasion of woody species. Of particular interest are the large stands of juniper ("Juniperus communis") on Bulford Downs and Beacon Hill. Both pyramidal and prostrate forms are present and this site, along with Porton Down SSSI to the south, supports the best remaining examples of the lowland type of juniper associated with chalk and mixed scrub in England.
Insects.
The botanically and structurally diverse grasslands support a large range of rare and uncommon chalk downland invertebrates. Where abundance has been assessed strong populations of national and local importance are present, and the large area of habitat available to them is important in ensuring their survival.
Butterflies.
The plain is an important stronghold for declining downland butterflies. A high concentration of colonies of three nationally scarce species, the Adonis blue ("Polyommatus bellargus"), Duke of Burgundy ("Hamearis lucina"), and the largest population of marsh fritillary ("Euphydryas aurinia") on the chalk, occur. A colony of brown hairstreak ("Thecla betulae") is present on East Salisbury Plain at one of its two Wiltshire localities. Strong populations of other downland species such as chalkhill blue ("Polyommatus coridon") and dark green fritillary ("Argynnis aglaja") are found, and of note here is the occurrence of grayling ("Hipparchia semele"), a butterfly rarely found away from the coast.
Moths.
An outstanding assemblage of two rare (RDB), 36 nationally scarce and two regionally notable moths are present, most of which are either chalk grassland specialists or are partly dependent on chalk grassland. The RDB species scarce forester ("Adscita globulariae") is present, and amongst many species of nationally scarce moths are the cistus forester ("Adscita geryon"), six-belted clearwing ("Bembecia scopigera"), oblique striped ("Phibalapteryx virgata"), pimpernel pug ("Eupithecia pimpinellata"), shaded pug ("Eupithecia subumbrata") and narrow-bordered bee hawk moth ("Hemaris tityus"). Larvae of these moths feed on the chalk grassland plants which are widespread on the plain. Other nationally scarce moths such as orange-tailed clearwing ("Synanthedon anthraciniformis") depend on the associated scrub habitats.
Bees.
The bee fauna is particularly rich in species which depend on chalk grassland. One of only two British populations of the endangered (RDB) mining bee "Melitta dimidiata" is present on the plain, and two other RDB species which occur are "Andrena hattorfiana" and its nest parasite the cuckoo bee "Nomada armata". This is a rare inland site for the nationally scarce brown-banded carder bee ("Bombus humilis"), and the only lowland English site for the broken-belted bumblebee ("Bombus soroeensis").
Flies.
The Diptera (flies) include four RDB species which depend on chalk grassland, the picture-wing flies "Chaetorellia loricata", "Urophora solstitialis" and "Terellia vectensis" and the hover fly "Volucella inflata".
Crustaceans.
Recent observations have shown that Salisbury Plain is an important site for the RDB crustacean, the fairy shrimp "Chirocephalus diaphanus" which is dependent on temporary pools, a rare and declining habitat. On the plain this habitat requirement is met by numerous pools created by repeated tank movements along the earth tracks which cross the chalk grassland.
Others.
Other nationally scarce invertebrates occur within the Orthoptera (grasshoppers and crickets), Heteroptera (bugs) and Coleoptera (beetles), the latter group including a RDB soldier beetle, "Cantharis fusca".
Birds.
The area as a whole is of national and international importance for breeding and wintering birds. It supports seven species listed on Annex 1 of the EC Directive on the Conservation of Wild Birds, populations of six species of Red Data bird and several species of candidate Red Data bird. Amongst the breeding birds three species are particularly noteworthy. Up to 20 pairs of stone curlew representing 12% of the British population breed on the plain. The area accounts for approximately 20% of breeding records for quail in Britain each year, and numbers of breeding Hobby are thought to exceed 1% of the British population on a regular basis. Other important breeding species include buzzard, barn owl, long-eared owl, nightingale, stonechat, whinchat, wheatear, corn bunting and, on occasion, Montagu's harrier.
The overall breeding assemblage is exceptionally diverse for a British dry grassland site. In winter the plain is an important area for foraging flocks of thrushes, finches and buntings. These, together with abundant small mammals are prey for wintering hen harrier, merlin and short-eared owl. Hen harriers occur in nationally significant numbers each winter, and the plain is an important winter roost for this species in southern England.
In 2003 the great bustard was reintroduced into Britain on Salisbury Plain.
Snakes and amphibians.
Other species of interest on Salisbury Plain include the great crested newt ("Triturus cristatus"). This newt occurs in dew ponds across the plain and in pools along the Bourne River, together with smooth newt ("Triturus vulgaris"), common frog ("Rana temporia") and common toad ("Bufo bufo"). Barred grass snake ("Natrix helvetica") are also often seen near pools, and common lizard ("Lacerta vivipara"), slowworm ("Anguis fragilis") and adder ("Vipera berus") are present.


Samuel Rowbotham

Samuel Birley Rowbotham (; 1816 – 23 December 1884, in London) was an English inventor and writer who wrote "Zetetic Astronomy: Earth Not a Globe" under the pseudonym Parallax. His work was originally published as a 16-page pamphlet (1849), and later expanded into a book (1865).
Rowbotham's method, which he called zetetic astronomy, models the Earth as a flat disc centered at the North Pole and bounded along its perimeter by a wall of ice, with the Sun, Moon, planets, and stars moving only several thousand miles above the surface of Earth.
Life.
Rowbotham started out as an organiser of an Owenite commune in The Fens, where he formulated his theories about the Earth. After measuring a lack of curvature on the long straight drainage ditches of the Bedford Levels in his first Bedford Level experiment, he was convinced of the flatness of the Earth and began to lecture on the topic. He took a little time to learn his trade, running away from a lecture in Blackburn when he couldn't explain why the hulls of ships disappeared before their masts when sailing out to sea. However, as he persisted in filling halls by charging sixpence a lecture, his quick-wittedness and debating skills were honed so much that he could "counter every argument with ingenuity, wit and consummate skill".
When finally pinned down to a challenge in Plymouth in 1864 by allegations that he wouldn't agree to a test, Parallax appeared on Plymouth Hoe at the appointed time, witnessed by Richard A. Proctor, a writer on astronomy, and proceeded to the beach where a telescope had been set up. His opponents had claimed that only the lantern of the Eddystone Lighthouse, some 14 miles out to sea, would be visible. In fact, only half the lantern was visible, yet Rowbotham claimed his opponents were wrong and that it proved the Earth was indeed flat so that many Plymouth folk left the Hoe agreeing that "some of the most important conclusions of modern astronomy had been seriously invalidated".
In 1861, Rowbotham married for a second time (to the 16-year-old daughter of his laundress) and settled in London, producing 14 children, of whom four survived. He was also alleged to be using the name "Dr. Samuel Birley", living in a beautiful 12-roomed house, selling the secrets for prolonging human life and curing every disease imaginable. Augustus De Morgan refers to him as S. Goulden. He patented a number of inventions, including a "life-preserving cylindrical railway carriage".
His book "Zetetic Astronomy: The Earth not a Globe" appeared in 1864. His lectures continued and concerned citizens addressed letters to the Astronomer Royal seeking rebuttals for his claims. A correspondent to the Leeds Times observed that "One thing he did demonstrate was that scientific dabblers unused to platform advocacy are unable to cope with a man, a charlatan if you will (but clever and thoroughly up in his theory), thoroughly alive to the weakness of his opponents".
Influence.
One of Rowbotham's followers, John Hampden, a Christian polemicist, gained notoriety by engaging in raucous public debates with leading scientists of the day. A bet involving the prominent naturalist Alfred Russel Wallace in the famous Bedford Level experiment led to several lawsuits for fraud and libel and Hampden's imprisonment.
In the United States, Rowbotham's ideas were taken up by the Christian Catholic Apostolic Church and promoted widely on their radio station. His work in the United States was continued by William Carpenter. Carpenter, a printer originally from Greenwich, England, a supporter of Rowbotham and published "Theoretical Astronomy Examined and Exposed — Proving the Earth not a Globe" in eight parts from 1864 under the name "Common Sense". He later emigrated to Baltimore where he published "A hundred proofs the Earth is not a Globe" in 1885.
Legacy.
After Rowbotham's death, Lady Elizabeth Blount continued the "Universal Zetetic Society" which Rowbotham had founded. They published a magazine entitled "The Earth Not a Globe Review" and remained active well into the early part of the 20th century. After World War I, the movement underwent a slow decline, but it was revived in 1956 as The Flat Earth Society.


779 Nina

779 Nina ("prov. designation": "or" ) is a large background asteroid, approximately in diameter, located in the central region of the asteroid belt. It was discovered on 25 January 1914, by Russian astronomer Grigory Neujmin at the Simeiz Observatory on the Crimean peninsula. The metallic X-type asteroid with an intermediate albedo has a rotation period of 11.2 hours. It was named after the discoverer's sister, Nina Neujmina (1877–1956).
Orbit and classification.
"Nina" is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the central main-belt at a distance of 2.1–3.3 AU once every 4 years and 4 months (1,588 days; semi-major axis of 2.66 AU). Its orbit has an eccentricity of 0.23 and an inclination of 15° with respect to the ecliptic. The body's was first observed as and at Heidelberg Observatory on 16 December 1908 and 14 October 1912, respectively. The observation arc begins at Vienna Observatory on 31 July 1916, more than two years after to its official discovery observation at Simeiz Observatory on Crimea.
Naming.
This minor planet was after Nina Nikolaevna Neujmina (1877–1956), mathematician and sister of Russian discoverer Grigory Neujmin.
Physical characteristics.
In the Bus–Binzel SMASS classification, "Nina" is an X-type asteroid. It is also an X-type in both the Tholen- and SMASS-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2). Belskaya classifies "Nina" as a metallic M-type asteroid, which is the equivalent spectral type in the Tholen taxonomy for X-types with an intermediate albedo "(see below)".
Rotation period.
In June 1981, a rotational lightcurve of "Nina" was obtained from photometric observations by Alan Harris at the Table Mountain and Lowell observatories. Lightcurve analysis gave a rotation period of hours with a brightness variation of magnitude (). It was confirmed by Brian Warner at his Palmer Divide Observatory in Colorado in January 2009, who determined a period of hours with an amplitude of magnitude (). In September 2012, French amateur astronomer Gérald Rousseau obtained a period of hours with an amplitude of magnitude ().
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), and the Japanese Akari satellite, "Nina" measures (), () and () kilometers in diameter and its surface has an albedo of (), () and (), respectively. The "Collaborative Asteroid Lightcurve Link" adopts Petr Pravec's revised WISE-albedo of 0.1694 and takes a diameter of 77.46 kilometers based on an absolute magnitude of 8.1. The WISE team also published an alternative mean-diameter of () with an albedo of (). On 10 November 2005, an asteroid occultation of "Nina" gave a best-fit ellipse dimension of (), with a quality rating of 2. These timed observations are taken when the asteroid passes in front of a distant star.


589 Croatia

Croatia (minor planet designation: 589 Croatia), provisional designation , is a dark asteroid and parent body of the Croatia family, located in the outer regions of the asteroid belt, approximately 88 kilometers in diameter. It was discovered in 1906, by astronomer August Kopff at Heidelberg Observatory, and later named for the independent country of Croatia, then part of Austria-Hungary.
Discovery.
The asteroid was discovered on 3 March 1906, by German astronomer August Kopff at the Heidelberg-Königstuhl State Observatory in southwest Germany, with the use of the photographic method. In the moment of the discovery, the asteroid was 12.5mv and was in the constellation of Virgo. The discovery was published in the "Astronomische Nachrichten" magazine, in the article wrote by Professor Wolf. Later, some astronomers (Johann Palisa, Karl Lohnert and some others) were making measurements for the purpose of determining the orbital elements. From these measurements P. V. Neugebauer from Berlin and M.S. Mello and Simas from Trafaria (Lisbon) had independently determined the first orbital elements. Observations had continued, and among observers there were A. Kopff, E. Bianchi, A. Abetti, G. Zappa, P. Chafardet, E. Millosevich, J. Palisa, and some others. Observations were made from Berlin, Copenhagen, Rome, Arcetra and some other Italian cities.
Orbit and classification.
"Croatia" is the parent body of the Croatia family (), a small asteroid family of less than 100 known members. It orbits the Sun in the outer main belt at a distance of 3.0–3.3 AU once every 5 years and 7 months (2,032 days; semi-major axis of 3.14 AU). Its orbit has an eccentricity of 0.04 and an inclination of 11° with respect to the ecliptic. The body's observation arc begins at Heidelberg, sixteen days after its official discovery observation.
Physical characteristics.
In the Tholen classification, "Croatia" is ambiguous, closest to a carbonaceous C-type and somewhat similar to that of an X-type asteroid, while the Wide-field Infrared Survey Explorer (WISE) characterized it as a primitive P-type asteroid. Nesvorný determined the overall spectral type for the Croatia family to be that of an X-type.
Rotation period.
In July 2013, the so-far best-rated rotational lightcurve of "Croatia" was obtained by astronomers Romain Montaigut, Arnaud Leroy, Raoul Behrend, René Roy, Donn Starkey, Maurice Audejean, Roberto Crippa and Federico Manzini. Lightcurve analysis gave a longer-than average rotation period of 24.821 hours with a brightness variation of 0.25 magnitude (). The result supersedes photometric observations by Brian Warner and by astronomers at the Palomar Transient Factory, which measured a shorter period of 11.7 and 16.385 hours with an amplitude of 0.16 and 0.32, respectively ().
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's WISE telescope, "Croatia" measures between 84.44 and 96.491 kilometers in diameter and its surface has an albedo between 0.041 and 0.06.
The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0577 and a diameter of 87.66 kilometers based on an absolute magnitude of 9.0. The radius of (probably) 28.452 km (and, consequently, the superficial area of 2543.2 km2, and equatorial circumference of 89.385 km) were determined by use of Argelander's Method.
Naming.
This minor planet was named for the country of Croatia, then part of Austria-Hungary, after the suggestion made by astronomer Max Wolf. It also honors the foundation of the Astronomical Observatory of the Croatian Natural Sciences Society (Zagreb Observatory) in Zagreb.


Isogenous series

Isogenous is a term occasionally used in spectroscopy that denotes when two or more spectroscopic series of transition from a common state. The word was first used in this context in T.J. Stone & R.F. Barrow "Laser excited fluorescence spectra of gaseous formula_1", Canadian Journal of Physics. Vol. 53, p. 1976, October 1975. In this case, an excited state of gaseous formula_1 was pumped by an Argon ion laser; the excited state then relaxed to two closely separated low lying states giving two series of emission lines with a common origin.


Hugh Wilson (RAF officer)

Hugh Joseph Wilson known as (28 May 1908 5 September 1990), nicknamed "Willie", was a senior Royal Air Force officer. He served as the RAF's main chief test pilot for captured enemy aircraft in World War II and in November 1945 was the first man to exceed , flying a Gloster Meteor jet fighter.
Biography.
Born in 1908, Wilson was the only son of Alfred Wilson and Jessie (née Wood Young). He was educated at Hastings' University School, Merchant Taylors' School in Northwood and City of London School. After leaving school he began an apprenticeship with a cotton manufacturer.
RAF career.
On 13 September 1929, Wilson joined the RAF within the General Duties Branch on a short service commission. He trained at the No. 5 Flight Training School and was later posted to No. 111 Squadron. Exactly five years after joining the RAF in 1934 he was placed on the Reserve of Air Force Officers. Whilst on this reserve list he passed a conversion course on flying boats and also passed as a flying instructor.
In the mid-1930s he worked as a test pilot for Blackburn Aircraft and was, in 1938, the first to fly the Blackburn Roc. He later worked at the Royal Aircraft Establishment at Farnborough as a civil test pilot.
World War II.
Recalled to active service with the RAF in 1939, Wilson was the Commanding Officer of the Aerodynamic Flight of the RAE at RAF Farnborough.
Between 1941 and the end of the war Wilson was the RAF's main test pilot on all captured enemy aircraft. Flying these aircraft from RAF Farnborough (they had been repainted with RAF roundels), Wilson would evaluate their handling and performance (see Armin Faber incident).
After a short period working in America as a test pilot, Wilson joined No. 616 Squadron in 1944 to train pilots on Britain's first jet fighter, the Gloster Meteor. He subsequently became Officer Commanding of the Empire Test Pilots' School at RAF Cranfield.
World air speed record.
On 7 November 1945, flying the Gloster Meteor "Britannia" (EE454) over a course at Herne Bay in Kent, Wilson averaged a new world air speed record for a jet fighter of .
Later career.
After leaving the RAF with the rank of Group Captain, Wilson worked as an engine salesman for Blackburn Aircraft and Rolls-Royce.
Personal life.
Wilson was married twice, first to Isobel Moira Sergeant in 1947 (they had one son) and then in 1959 to Patricia Frances Shanley Warren and had two more sons. He died on the 5th September 1990 and was buried in a family grave in Highgate Cemetery.


Adobe Wallaby

Adobe Wallaby is an application that turns FLA files into HTML5. On March 8, 2011, Adobe Systems released the first version of an experimental Flash (FLA files) to HTML5 converter, code named "Wallaby". It has been quickly superseded by various other Adobe tools.
Support.
Adobe Wallaby supports almost half of all the functions in Adobe Flash, such as, Gradients, Buttons, and Scenes. However, there are also some functions that it does not support, for example, ActionScript 1-3, and 3D transforms.


List of quarter tone pieces

A selection of compositions using quarter tones:


Principal meridians of Alaska

The five principal meridians of Alaska are the Copper River meridian (established 1905), Fairbanks meridian (adopted 1910), Kateel River meridian (adopted 1956), Seward meridian (adopted 1911) and Umiat meridian (adopted 1956).


List of sundial mottos

Many sundials bear a motto to reflect the sentiments of its maker or owner.
References.
Notes
Footnotes


Maximum spacing estimation

In statistics, maximum spacing estimation (MSE or MSP), or maximum product of spacing estimation (MPS), is a method for estimating the parameters of a univariate statistical model. The method requires maximization of the geometric mean of "spacings" in the data, which are the differences between the values of the cumulative distribution function at neighbouring data points.
The concept underlying the method is based on the probability integral transform, in that a set of independent random samples derived from any random variable should on average be uniformly distributed with respect to the cumulative distribution function of the random variable. The MPS method chooses the parameter values that make the observed data as uniform as possible, according to a specific quantitative measure of uniformity.
One of the most common methods for estimating the parameters of a distribution from data, the method of maximum likelihood (MLE), can break down in various cases, such as involving certain mixtures of continuous distributions. In these cases the method of maximum spacing estimation may be successful.
Apart from its use in pure mathematics and statistics, the trial applications of the method have been reported using data from fields such as hydrology, econometrics, magnetic resonance imaging, and others.
History and usage.
The MSE method was derived independently by Russel Cheng and Nik Amin at the University of Wales Institute of Science and Technology, and Bo Ranneby at the Swedish University of Agricultural Sciences. The authors explained that due to the probability integral transform at the true parameter, the “spacing” between each observation should be uniformly distributed. This would imply that the difference between the values of the cumulative distribution function at consecutive observations should be equal. This is the case that maximizes the geometric mean of such spacings, so solving for the parameters that maximize the geometric mean would achieve the “best” fit as defined this way. justified the method by demonstrating that it is an estimator of the Kullback–Leibler divergence, similar to maximum likelihood estimation, but with more robust properties for some classes of problems.
There are certain distributions, especially those with three or more parameters, whose likelihoods may become infinite along certain paths in the parameter space. Using maximum likelihood to estimate these parameters often breaks down, with one parameter tending to the specific value that causes the likelihood to be infinite, rendering the other parameters inconsistent. The method of maximum spacings, however, being dependent on the difference between points on the cumulative distribution function and not individual likelihood points, does not have this issue, and will return valid results over a much wider array of distributions.
The distributions that tend to have likelihood issues are often those used to model physical phenomena. seek to analyze flood alleviation methods, which requires accurate models of river flood effects. The distributions that better model these effects are all three-parameter models, which suffer from the infinite likelihood issue described above, leading to Hall's investigation of the maximum spacing procedure. , when comparing the method to maximum likelihood, use various data sets ranging from a set on the oldest ages at death in Sweden between 1905 and 1958 to a set containing annual maximum wind speeds.
Definition.
Given an iid random sample {"x"1, ..., "x""n"} of size "n" from a univariate distribution with continuous cumulative distribution function "F"("x";"θ"0), where "θ"0 ∈ Θ is an unknown parameter to be estimated, let {"x"(1), ..., "x"("n")} be the corresponding ordered sample, that is the result of sorting of all observations from smallest to largest. For convenience also denote "x"(0) = −∞ and "x"("n"+1) = +∞.
Define the "spacings" as the “gaps” between the values of the distribution function at adjacent ordered points:
Then the maximum spacing estimator of "θ"0 is defined as a value that maximizes the logarithm of the geometric mean of sample spacings:
By the inequality of arithmetic and geometric means, function "S""n"("θ") is bounded from above by −ln("n"+1), and thus the maximum has to exist at least in the supremum sense.
Note that some authors define the function "S""n"("θ") somewhat differently. In particular, multiplies each "D""i" by a factor of ("n"+1), whereas omit the factor in front of the sum and add the “−” sign in order to turn the maximization into minimization. As these are constants with respect to "θ", the modifications do not alter the location of the maximum of the function "S""n".
Examples.
This section presents two examples of calculating the maximum spacing estimator.
Example 1.
Suppose two values "x"(1) = 2, "x"(2) = 4 were sampled from the exponential distribution "F"("x";"λ") = 1 − e−"xλ", "x" ≥ 0 with unknown parameter "λ" > 0. In order to construct the MSE we have to first find the spacings:
The process continues by finding the "λ" that maximizes the geometric mean of the “difference” column. Using the convention that ignores taking the ("n"+1)st root, this turns into the maximization of the following product: (1 − e−2"λ") · (e−2"λ" − e−4"λ") · (e−4"λ"). Letting "μ" = e−2"λ", the problem becomes finding the maximum of "μ"5−2"μ"4+"μ"3. Differentiating, the "μ" has to satisfy 5"μ"4−8"μ"3+3"μ"2 = 0. This equation has roots 0, 0.6, and 1. As "μ" is actually e−2"λ", it has to be greater than zero but less than one. Therefore, the only acceptable solution is
which corresponds to an exponential distribution with a mean of ≈ 3.915. For comparison, the maximum likelihood estimate of λ is the inverse of the sample mean, 3, so "λ"MLE = ⅓ ≈ 0.333.
Example 2.
Suppose {"x"(1), ..., "x"("n")} is the ordered sample from a uniform distribution "U"("a","b") with unknown endpoints "a" and "b". The cumulative distribution function is "F"("x";"a","b") = ("x"−"a")/("b"−"a") when "x"∈["a","b"]. Therefore, individual spacings are given by
Calculating the geometric mean and then taking the logarithm, statistic "S""n" will be equal to
Here only three terms depend on the parameters "a" and "b". Differentiating with respect to those parameters and solving the resulting linear system, the maximum spacing estimates will be
These are known to be the uniformly minimum variance unbiased (UMVU) estimators for the continuous uniform distribution. In comparison, the maximum likelihood estimates for this problem formula_7 and formula_8 are biased and have higher mean-squared error.
Properties.
Consistency and efficiency.
The maximum spacing estimator is a consistent estimator in that it converges in probability to the true value of the parameter, "θ"0, as the sample size increases to infinity. The consistency of maximum spacing estimation holds under much more general conditions than for maximum likelihood estimators. In particular, in cases where the underlying distribution is J-shaped, maximum likelihood will fail where MSE succeeds. An example of a J-shaped density is the Weibull distribution, specifically a shifted Weibull, with a shape parameter less than 1. The density will tend to infinity as "x" approaches the location parameter rendering estimates of the other parameters inconsistent.
Maximum spacing estimators are also at least as asymptotically efficient as maximum likelihood estimators, where the latter exist. However, MSEs may exist in cases where MLEs do not.
Sensitivity.
Maximum spacing estimators are sensitive to closely spaced observations, and especially ties. Given
we get
When the ties are due to multiple observations, the repeated spacings (those that would otherwise be zero) should be replaced by the corresponding likelihood. That is, one should substitute formula_11 for formula_12, as
since formula_14.
When ties are due to rounding error, suggest another method to remove the effects.
Given "r" tied observations from "x""i" to "x""i"+"r"−1, let "δ" represent the round-off error. All of the true values should then fall in the range formula_15. The corresponding points on the distribution should now fall between formula_16 and formula_17. Cheng and Stephens suggest assuming that the rounded values are uniformly spaced in this interval, by defining
The MSE method is also sensitive to secondary clustering. One example of this phenomenon is when a set of observations is thought to come from a single normal distribution, but in fact comes from a mixture normals with different means. A second example is when the data is thought to come from an exponential distribution, but actually comes from a gamma distribution. In the latter case, smaller spacings may occur in the lower tail. A high value of "M"("θ") would indicate this secondary clustering effect, and suggesting a closer look at the data is required.
Moran test.
The statistic "Sn"("θ") is also a form of Moran or Moran-Darling statistic, "M"("θ"), which can be used to test goodness of fit.
It has been shown that the statistic, when defined as
is asymptotically normal, and that a chi-squared approximation exists for small samples. In the case where we know the true parameter formula_20, show that the statistic formula_21 has a normal distribution with
where "γ" is the Euler–Mascheroni constant which is approximately 0.57722.
The distribution can also be approximated by that of formula_23, where
in which
and where formula_26 follows a chi-squared distribution with formula_27 degrees of freedom. Therefore, to test the hypothesis formula_28 that a random sample of formula_27 values comes from the distribution formula_30, the statistic formula_31 can be calculated. Then formula_28 should be rejected with significance formula_33 if the value is greater than the critical value of the appropriate chi-squared distribution.
Where "θ"0 is being estimated by formula_34, showed that formula_35 has the same asymptotic mean and variance as in the known case. However, the test statistic to be used requires the addition of a bias correction term and is:
where formula_37 is the number of parameters in the estimate.
Generalized maximum spacing.
Alternate measures and spacings.
 generalized the MSE method to approximate other measures besides the Kullback–Leibler measure. further expanded the method to investigate properties of estimators using higher order spacings, where an "m"-order spacing would be defined as formula_38.
Multivariate distributions.
 discuss extended maximum spacing methods to the multivariate case. As there is no natural order for formula_39, they discuss two alternative approaches: a geometric approach based on Dirichlet cells and a probabilistic approach based on a “nearest neighbor ball” metric.


725 Amanda

725 Amanda ("prov. designation:" "or" ) is a dark background asteroid, approximately in diameter, that is located in the central regions of the asteroid belt. It was discovered by Austrian astronomer Johann Palisa at the Vienna Observatory on 21 October 1911. The carbonaceous C-type asteroid (CSU/C0) has a short rotation period of 3.7 hours. It was named after Amanda Schorr, wife of German astronomer Richard Schorr (1867–1951).
Orbit and classification.
"Amanda" is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the central asteroid belt at a distance of 2.0–3.1 AU once every 4 years and 2 months (1,507 days; semi-major axis of 2.57 AU). Its orbit has an eccentricity of 0.22 and an inclination of 4° with respect to the ecliptic. The body's observation arc begins at Vienna Observatory on 29 September 1915, almost four years after its official discovery observation.
Naming.
This minor planet was named after Amanda Schorr, wife of Richard Schorr (1867–1951), a German astronomer at Bergedorf Observatory, after whom asteroid 1235 Schorria and lunar crater "Schorr" were named. The asteroid's name was proposed by Palisa in 1913, on the occasion of the 24th meeting of the "Astronomische Gesellschaft" in Hamburg, Germany (). The was also mentioned in "The Names of the Minor Planets" by Paul Herget in 1955 ().
Physical characteristics.
In the Tholen classification, "Amanda"s spectral type is closest to that of a carbonaceous C-type asteroid, yet also somewhat similar to a stony S-type with an "unusual" spectrum (CSU). In the taxonomy by Barucci (1987), the asteroid is a dark C-type (C0).
Rotation period and poles.
A rotational lightcurve of "Amanda" was obtained from photometric observations by European astronomers at the La Silla Observatory before 1995. Lightcurve analysis gave a well-defined rotation period of hours with a brightness variation of magnitude ().
In October 2010, French amateur astronomer Maurice Audejean determined a concurring period of () hours with an amplitude of () magnitude (), while in August 2018, a further observation by the TESS-team reported a period of () hours and an amplitude of () magnitude ().
In 2016, a modeled lightcurve gave a sidereal period of hours using data from the Uppsala Asteroid Photometric Catalogue, the Palomar Transient Factory survey, and individual observers, as well as sparse-in-time photometry from the NOFS, the Catalina Sky Survey, and the La Palma surveys . The study also determined two spin axes of (145.0°, −63.0°) and (320.0°, −70.0°) in ecliptic coordinates (λ, β).
Diameter and albedo.
According to the surveys carried out by the Japanese Akari satellite, the Infrared Astronomical Satellite IRAS, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), "Amanda" measures (), () and () in diameter and its surface has an albedo of (), () and (), respectively.
The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0824 and calculates a diameter of 21.56 kilometers based on an absolute magnitude of 11.66. Alternative mean-diameters published by the WISE team include (), (), () and () with a corresponding albedo of (), (), () and ().


847 Agnia

847 Agnia is a minor planet orbiting the Sun. It is approximately 28 kilometers in diameter.
The spectrum of this object indicates that it is an S-type asteroid with both low and high calcium forms of pyroxene on the surface, along with less than 20% olivine. The high-calcium form of pyroxene forms 40% or more of the total pyroxene present, indicating a history of igneous rock deposits. This suggests that the asteroid underwent differentiation by melting, creating a surface of basalt rock.
847 Agnia is the namesake of the Agnia family of asteroids that share similar orbital elements and physical properties. The members of this family, including 847 Agnia, most likely formed from the breakup of a basalt object, which in turn was spawned from a larger parent body that had previously undergone igneous differentiation. Other members of this family include 1020 Arcadia, 1228 Scabiosa, 2401 Aehlita, and 3395 Jitka
Photometric observations of this asteroid collected during 2004–2005 show a rotation period of 14.827 ± 0.001 hours with a brightness variation of 0.45 ± 0.03 magnitude.


Contact microphone

A contact microphone, also known as a piezo microphone, is a form of microphone that senses audio vibrations through contact with solid objects. Unlike normal air microphones, contact microphones are almost completely insensitive to air vibrations but transduce only structure-borne sound. Often used as acoustic leakage probes, they also enjoy wide usage by noise music artists experimenting with sound. Contact microphones can be used to amplify sound from acoustic musical instruments, to sense drum hits, for triggering electronic samples, and to record sound in challenging environments, such as underwater under high pressure.
Contact microphones based on piezo materials are passive and high-impedance, which can make them sound 'tinny' without a matching preamp.
The most commonly available contact microphone element is made of a thin piezoelectric ceramic round glued to a thin brass or alloy metal disc. This center disc is positively charged while the brass disc is negatively charged. If the silver disc is cracked or scorched, the piezo will no longer function at full sensitivity.


Derek Jackson

Derek Ainslie Jackson, OBE, DFC, AFC, FRS (23 June 1906 – 20 February 1982) was a spectroscopist and also a jockey. Derek Jackson was one of the outstanding atomic physicists of his generation.
Biography.
Son of a wealthy Welshman, Sir Charles Jackson, who was both a leading authority on antique silver and chairman of the "News of the World", Jackson showed early promise in the field of spectroscopy under the guidance of Professor Lindemann, making the first quantitative determination of a nuclear magnetic spin using atomic spectroscopy to measure the hyperfine structure of caesium.
His scientific research at Oxford did not, however, interfere with his other great passion – steeplechase riding – which led him from the foxhunting field to his first ride in the Grand National of 1935. A keen huntsman, he took up the sport again after the war, riding in two more Nationals after the war, the last time when he was 40 years old.
In World War II, Jackson distinguished himself in the RAF, making an important scientific contribution to Britain's air defences and to the bomber offensive. He flew more than a thousand hours as a navigator, many of them in combat in night-fighters, with No. 604 (County of Middlesex) Squadron based at RAF Middle Wallop. He was decorated with the DFC, AFC and OBE.
This war record stands in contrast to his stated desire at the war's inception to keep Britain out of fighting Germany, and his reported desire "that all Jews in England should be killed".
For the rest of his life, Jackson, appointed a Fellow of the Royal Society in 1947, lived as a tax exile in Ireland, France and Switzerland. He continued his spectroscopic work in France at the Centre national de la recherche scientifique, and was made a chevalier de la Légion d'honneur.
Jackson had what might be called a colourful personal life. A "rampant bisexual", he was married six times, and also lived for three years with Angela Culme-Seymour, the half-sister of Janetta Wooley, one of his wives. The others included a daughter of Augustus John, Pamela Mitford (one of the Mitford sisters), a princess and several femme fatales including Barbara Skelton (in whose obituary in the Independent is noted her remark that it was "not for love that (she) married Professor Jackson", he being identified as "the millionaire son of the founder of the News of the World").


Hamilton Underground Film Festival

The Hamilton Underground Film Festival was an annual film festival held in Hamilton, New Zealand between 2006 and 2013. Run on the basis of a DIY ethos the festival was open to all and had no admission fee for film entries. Each entrant received a DVD which contains all the entered films. The festival was the longest running festival of its kind in Australasia until recent usurped by the Melbourne underground film festival.
There was a yearly section for experimental fone films, Super 8 mm film and subverts. Since 2009 the festival featured a collaborative digital film section in which participants operate under the same name: Karen Karnak There is also a special remix section where films can be entered under a Attribution-Noncommercial-Share Alike 3.0 Unported creative commons license. This will allow other contributors to remix selected works and create collaborative works.
History.
The Hamilton Underground Film Festival was a yearly event showcasing national and international underground film presented in Hamilton, New Zealand. It was founded in 2006 by the Otatoe Collective under the guidance of Emit Snake-Beings. and has since been gathering momentum with over 100 filmmakers featured and linked events in Catalonia, Spain, Kingston upon Hull, and London.
The 2010 featured a talk and presentation by Jed Town from Fetus products. The 2009 event: local films plus a director's talk by David Blyth the New Zealand alternative filmmaker. The 2008 event featured a live internet link to the Priorat region of Catalonia where the simultaneous 4th Hamilton Underground Film Festival was hosted by Oscar Hidalgo. The 2008 screenings included: Director Campbell Cooley and his film The Heist (short film), Expanded Cinema from the Parasitical Fantasy Band - as featured in otherfilm festival Brisbane 2006 and Greg Locke's Internationally acclaimed robot band The Trons.
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Karen Karnak.
The festival have created an open source multiple-use name called Karen Karnak. The name is available for anyone to create work under and there will be a special section in the festival for work by Karen Karnak. The aim of the multiple-use name Karen Karnak is to examine the space with surrounds the filmmaker and to create visual work from the emptiness or more accurately the Shunyata.
Films and filmmakers.
Watching. Martin Rumsby (:59)
San Antoni. Arnolfini ( 5:38)
The Trons Snake-Beings ( 2:40)
Symbol Gerard Gil ( :10)
Cyclic Existence Bonnie Hart ( :23)
Shall I be Mother. Dan Inglis ( 2:26)
Between the Lines. Christian Parahi ( 4:43)
Cholera Clocks. Snake-Beings ( 4:55)
Barbie Buddah Nylstoch ( :41)
Symbol Gerard Gil ( :10)
Blue Tide, Black Water Eve Gorden & Sam Hamilton ( 9:04)
Ensalada de Ruido Yolanda Cañardo Galve ( 1:01)
Bugged Otatoe C ( :10)
Moth Campbell Farquhar ( 4:11)
NZ es el culo Octpob ( :10)
Zaks Cake Octpob ( :48)
Solstici Gerard Gil ( 2:01)
Sintaxis B. Ferrando ( 2:23)
Ehen: el horizonte está nublado Javi Neiro and Océ Anos ( 2:35)
Symbol Gerard Gil ( :10)
Passion. Peter Caldwell ( 4:53)
Suspect device Octpob ( :03)
Ufo Jed Town ( 4:24)
The Heist Campbell Cooley ( 6:21)
Plastic Gods OctoC ( :16)
Pareidolia No Mendacity, Witcyst ( :21)
Grey News, Nylstoch ( :27)
Tinkernicks Mike Crook & Rosie Percival ( 2:51)
Al Final De La Via Gerard Gil ( 6:00)
Monk Carlos Pla ( 4:14)
Poeticas 3 B. Ferrando ( 3:24)
The Remote Viewers 2008 Snakebeings ( 13:39)
Car wash Pippa Russel ( 2:02)
American Sketch Book Martin Rumsby ( 7:55)
Night out with the artists Jenny Spark ( 4:37)
OKOK+circuit47 ( 1:50)
Petroquimica ( 1:58)
Sadie Wrestling Bryce Galloway ( 3:29)
Cuts from Rafel Marcos (1:17)
Untitled Otatoe ( 0:11)
Self Portrait as a Painter RG Shaw (3:11)
Pig in a Can CJ Finlayson ( 4:23)
Cube Hamilton street theatre collective ( 2:04)
Best of both worlds Thom Burton ( 2:34)
400 Mr Slepica ( 1:00)
Tria Prima Arnolfini ( 2:04)
Think Agent Bulldog ( 4:19)
Dios los Crean ( :03)
Abject leader Nylstoch ( :45)
Youyou RG Shaw_Mr_Slepica ( 6:04)
La Resposta de les Meves Sabates Yolanda Cañardo Galve (:59)
MICHELLE SAVILL – former WINTEC student presents her film ‘Martin and Snakes go to the Zoo’ fresh from the New York International Independent Film Festival. Martin and Snakes are, of course, Martin Webclaw formerly of the band Wendyhouse and intermedia artist Emit Snake-Beings.
JOE CITIZEN's recent computer scratch film with sound by Emit Snake-Being
MARTIN RUMSBY – New Zealand's experimental filmmaker, disappeared into Chicago's African American ghetto in 1995 shortly after co-founding X FILM CHICAGO. Long considered Missing in Action, Rumsby moved to Hamilton a few months ago where he has completed six films this year. Rumsby's short film LIVE challenges the authority of media representations and includes references to the war in Iraq. This will be the first public screening of a Martin Rumsby film in New Zealand since 1984. Rumsby also recently completed a film on the demise of the OVERLANDER passenger train service between Auckland and Wellington.
EMIT SNAKE-BEINGS – Founder of the Hamilton Underground Film Festival, composer, musician and electrical shrine maker, travelled in Europe for 12 years shooting films in Spain, Mexico, Fiji and Japan. Resident in Hamilton since 2000. Emit Snake-Beings will present his recently made stop frame puppet animation ‘Death of an Orchestra’
PIPSIX – Shows her 4 minute long film ‘Rabbit and Possum’ in which two common pests go fishing and drink beer together.
American filmmaker PHIL SECRIST's film MOMENTO MORI (2006) is a dark, surrealistic journey into death and time in which a man relives his life; certain doors open and close, leading him to his ultimate destination. Filmed in Hamilton.
The crazy vision of Auckland-based musician and filmmaker THOM BURTON, of the band Yokel Ono, in a random collection of shorts, including GREEN EYED MONSTERS and LE PESTSE, which mix suburban fantasy and nightmare.
ROSIE PERCIVAL's film Fellow is a 2 minute long experimental film using Adobe After Effects and featuring identical twins having a short conversation.
STEFAN NEVILLE / SUGAR JON / PUMICE – Ex Hamiltonian, now international noise music innovator – Stefan, a musical associate of Chris Knox and currently touring the US, and Sugar Jon chop wood in Dunedin to the raw sounds of Pumice-raft. (4 minutes.)
WITCYST – Internationally known noise magician from Whangarei has released over 700 tapes and 400 CDs – now working in visuals as well.
OCTPOB FILMS – miscellaneous New Zealand short films.
OKOK SOCIETY – A selection of scenes by mysterious film and sound Kaosmagician Mark Reeve sent directly to us from his base in Wales.
STEVE RIFE – USA Pyrotechnics expert and filmmaker from St. Paul, Minnesota
PATRICK MAUN - USA
OTATO COLLECTIVO – INTERNATIONAL/LOCAL collaborations and network group
See also.
Interview with Jed Town


4082 Swann

4082 Swann, provisional designation , is a carbonaceous asteroid from the inner regions of the asteroid belt, approximately 10 kilometers in diameter.
The asteroid was discovered on 27 September 1984, by American astronomer Carolyn Shoemaker at Palomar Observatory in California, United States, and later named for American geologist Gordon Swann.
Orbit and classification.
"Swann" orbits the Sun in the inner main-belt at a distance of 1.8–3.0 AU once every 3 years and 8 months (1,349 days). Its orbit has an eccentricity of 0.26 and an inclination of 10° with respect to the ecliptic. First identified as at the Finnish Turku Observatory in 1947, "Swann"s observation arc was extended by 37 years prior to its official discovery observation at Palomar.
Physical characteristics.
The C-type asteroid is classified as a Ch-subtype in the SMASS taxonomy.
Diameter and albedo.
According to the surveys carried out by the Japanese Akari satellite and NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, "Swann" measures 9.5 and 11.1 kilometers in diameter and its surface has an albedo of 0.029 and 0.101, respectively. The "Collaborative Asteroid Lightcurve Link", however, assumes a standard albedo for stony asteroids of 0.20 and derives a much smaller diameter of 5.85 kilometers, based on an absolute magnitude of 13.46.
Rotation period.
In July 2006, a rotational lightcurve of "Swann" was obtained from photometric observations by Petr Pravec at the Ondřejov Observatory in the Czech Republic. It gave a rotation period of hours with a brightness variation of 0.67 magnitude (). A second lightcurve obtained by Jean-Gabriel Bosch in September 2006, gave a period of hours and an amplitude of 0.35 magnitude ().
Naming.
This minor planet was named after American geologist Gordon A. Swann (born 1931). He served as the principal investigator of the "Apollo Lunar Geologic Experiment" conducted at the lunar landing sites of Apollo 14 and Apollo 15. The official naming citation was published by the Minor Planet Center on 12 December 1989 ().


Cleveland Stock Exchange

The Cleveland Stock Exchange was a stock exchange in Cleveland, Ohio, U.S..
History.
The Cleveland Stock Exchange was founded in a formal meeting on 1899 and began operations on April 16, 1900. In late October 1949 they voted to dissolve and join the Midwest Stock Exchange.


Leiden Shorts

Leiden Shorts is an annual short film festival held in the city of Leiden, The Netherlands. Leiden Shorts (previously known as Leiden International Short Film Experience) was founded in 2009 as a cineclub and has grown to become one of the Netherlands' largest international short film festivals.
History.
Leiden Shorts started off in 2009 as a spin-off of the University of Leiden Student Cinema Club. Since then, the festival has been grown to a four-day event exploring the borders between different sorts of art and providing a podium to established but especially young talented filmmakers, artists and musicians. Next to the main festival in spring, Leiden Shorts is involved in cultural events throughout the year in collaboration with several organizations in Leiden and surroundings. Examples are Leiden International Film Festival (LIFF), Leiden Observatory, RAP, Vrijplaats Leiden, Cultuurmaand, Nacht van Ondekkingen and Museumnacht Leiden.
Jury.
Since 2012, the festival has three categories of awards – General Award, Student Award and Audience award. Juries for both General and Student Award select one film for the designated awards. The Jury is generally composed of scholars, filmmakers and other film professionals alike. The audience votes during the festival and the results are announced on the last day of the festival.


Minute and second of arc

A minute of arc, arcminute (arcmin), arc minute, or minute arc, denoted by the symbol formula_1, is a unit of angular measurement equal to of one degree. Since one degree is of a turn (or complete rotation), one minute of arc is of a turn. The nautical mile was originally defined as a minute of latitude on a spherical Earth, so the actual Earth circumference is very near 21 600 nautical miles. A minute of arc is of a radian.
A second of arc, arcsecond (arcsec), or arc second, denoted by the symbol formula_2, is of an arcminute, of a degree, of a turn, and (about ) of a radian.
These units originated in Babylonian astronomy as sexagesimal subdivisions of the degree; they are used in fields that involve very small angles, such as astronomy, optometry, ophthalmology, optics, navigation, land surveying, and marksmanship.
To express even smaller angles, standard SI prefixes can be employed; the milliarcsecond (mas) and microarcsecond (μas), for instance, are commonly used in astronomy.
The number of square arcminutes in a complete sphere is formula_3 square arcminutes (the surface area of a unit sphere in square units, divided by the solid angle area subtended by a square arcminute (also in square units), so that the final result is a dimensionless number).
The fact that the terms "minute" and "second" also denote units of time derives from Babylonian astronomy, where the corresponding time-related terms denoted the duration of the Sun's apparent motion of one minute or one second of arc, respectively, through the ecliptic. In present terms, the Babylonian degree of time was four minutes long, so the "minute" of time was four seconds long and the "second" of a second.
Symbols and abbreviations.
The prime symbol (′) (U+2032) designates the arcminute, though a single quote (') (U+0027) is commonly used where only ASCII characters are permitted. One arcminute is thus written as 1′. It is also abbreviated as arcmin or amin or, less commonly, the prime with a circumflex over it (formula_4).
Similarly, double prime (″) (U+2033) designates the arcsecond, though a double quote (") (U+0022) is commonly used where only ASCII characters are permitted. One arcsecond is thus written as 1″. It is also abbreviated as arcsec or asec.
In celestial navigation, seconds of arc are rarely used in calculations, the preference usually being for degrees, minutes and decimals of a minute, for example, written as 42° 25.32′ or 42° 25.322′. This notation has been carried over into marine GPS receivers, which normally display latitude and longitude in the latter format by default.
Common examples.
The full moon's average apparent size is about 31 arcminutes (or 0.52°).
An arcminute is approximately the resolution of the human eye.
An arcsecond is approximately the angle subtended by a U.S. dime coin (18 mm) at a distance of . An arcsecond is also the angle subtended by
A milliarcsecond is about the size of a dime atop the Eiffel Tower, as seen from New York City.
A microarcsecond is about the size of a period at the end of a sentence in the Apollo mission manuals left on the Moon as seen from Earth.
A nanoarcsecond is about the size of a penny on Neptune's moon Triton as observed from Earth.
Also notable examples of size in arcseconds are:
Uses.
Astronomy.
Since antiquity, the arcminute and arcsecond have been used in astronomy: in the ecliptic coordinate system as latitude (β) and longitude (λ); in the horizon system as altitude (Alt) and azimuth (Az); and in the equatorial coordinate system as declination (δ). All are measured in degrees, arcminutes and arcseconds. The principal exception is right ascension (RA) in equatorial coordinates, which is measured in time units of hours, minutes, and seconds.
The arcsecond is also often used to describe small astronomical angles such as the angular diameters of planets (e.g. the angular diameter of Venus which varies between 10″ and 60″), the proper motion of stars, the separation of components of binary star systems, and parallax, the small change of position of a star in the course of a year, or of a solar system body as the Earth rotates. These small angles may also be written in milliarcseconds (mas), or thousandths of an arcsecond. The unit of distance, the parsec, named from the "par"allax of one arc "sec"ond, was developed for such parallax measurements. It is the distance at which the mean radius of the Earth's orbit (more precisely, one astronomical unit) would subtend an angle of one arcsecond.
The ESA astrometric satellite Gaia, launched in 2013, can approximate star positions to 7 microarcseconds (µas).
Apart from the Sun, the star with the largest angular diameter from Earth is R Doradus, a red giant with a diameter of 0.05″. Because of the effects of atmospheric blurring, ground-based telescopes will smear the image of a star to an angular diameter of about 0.5″; in poor conditions this increases to 1.5″ or even more. The dwarf planet Pluto has proven difficult to resolve because its angular diameter is about 0.1″.
Space telescopes are not affected by the Earth's atmosphere but are diffraction limited. For example, the Hubble Space Telescope can reach an angular size of stars down to about 0.1″. Techniques exist for improving seeing on the ground. Adaptive optics, for example, can produce images around 0.05″ on a 10 m class telescope.
Cartography.
Minutes (′) and seconds (″) of arc are also used in cartography and navigation. At sea level one minute of arc along the equator equals exactly one geographical mile along the Earth's equator or approximately . A second of arc, one sixtieth of this amount, is roughly . The exact distance varies along meridian arcs or any other great circle arcs because the figure of the Earth is slightly oblate (bulges a third of a percent at the equator).
Positions are traditionally given using degrees, minutes, and seconds of arcs for latitude, the arc north or south of the equator, and for longitude, the arc east or west of the Prime Meridian. Any position on or above the Earth's reference ellipsoid can be precisely given with this method. However, when it is inconvenient to use base-60 for minutes and seconds, positions are frequently expressed as decimal fractional degrees to an equal amount of precision. Degrees given to three decimal places ( of a degree) have about the precision of degrees-minutes-seconds ( of a degree) and specify locations within about . For navigational purposes positions are given in degrees and decimal minutes, for instance The Needles lighthouse is at 50º 39.734’N 001º 35.500’W.
Property cadastral surveying.
Related to cartography, property boundary surveying using the metes and bounds system relies on fractions of a degree to describe property lines' angles in reference to cardinal directions. A boundary "mete" is described with a beginning reference point, the cardinal direction North or South followed by an angle less than 90 degrees and a second cardinal direction, and a linear distance. The boundary runs the specified linear distance from the beginning point, the direction of the distance being determined by rotating the first cardinal direction the specified angle toward the second cardinal direction. For example, "North 65° 39′ 18″ West 85.69 feet" would describe a line running from the starting point 85.69 feet in a direction 65° 39′ 18″ (or 65.655°) away from north toward the west.
Firearms.
The arcminute is commonly found in the firearms industry and literature, particularly concerning the precision of rifles, though the industry refers to it as minute of angle (MOA). It is especially popular as a unit of measurement with shooters familiar with the imperial measurement system because 1 MOA subtends a circle with a diameter of 1.047 inches (which is often rounded to just 1 inch) at 100 yards ( at or 2.908 cm at 100 m), a traditional distance on American target ranges. The subtension is linear with the distance, for example, at 500 yards, 1 MOA subtends 5.235 inches, and at 1000 yards 1 MOA subtends 10.47 inches.
Since many modern telescopic sights are adjustable in half (), quarter () or eighth () MOA increments, also known as "clicks", zeroing and adjustments are made by counting 2, 4 and 8 clicks per MOA respectively.
For example, if the point of impact is 3 inches high and 1.5 inches left of the point of aim at 100 yards (which for instance could be measured by using a spotting scope with a calibrated reticle), the scope needs to be adjusted 3 MOA down, and 1.5 MOA right. Such adjustments are trivial when the scope's adjustment dials have a MOA scale printed on them, and even figuring the right number of clicks is relatively easy on scopes that "click" in fractions of MOA. This makes zeroing and adjustments much easier:
Another common system of measurement in firearm scopes is the milliradian (mrad). Zeroing an mrad based scope is easy for users familiar with base ten systems. The most common adjustment value in mrad based scopes is  mrad (which approximates MOA).
One thing to be aware of is that some MOA scopes, including some higher-end models, are calibrated such that an adjustment of 1 MOA on the scope knobs corresponds to exactly 1 inch of impact adjustment on a target at 100 yards, rather than the mathematically correct 1.047 inches. This is commonly known as the Shooter's MOA (SMOA) or Inches Per Hundred Yards (IPHY). While the difference between one true MOA and one SMOA is less than half of an inch even at 1000 yards, this error compounds significantly on longer range shots that may require adjustment upwards of 20–30 MOA to compensate for the bullet drop. If a shot requires an adjustment of 20 MOA or more, the difference between true MOA and SMOA will add up to 1 inch or more. In competitive target shooting, this might mean the difference between a hit and a miss.
The physical group size equivalent to "m" minutes of arc can be calculated as follows: group size = tan() × distance. In the example previously given, for 1 minute of arc, and substituting 3,600 inches for 100 yards, 3,600 tan() ≈ 1.047 inches. In metric units 1 MOA at 100 metres ≈ 2.908 centimetres.
Sometimes, a precision-oriented firearm's performance will be measured in MOA. This simply means that under ideal conditions (i.e. no wind, high-grade ammo, clean barrel, and a stable mounting platform such as a vise or a benchrest used to eliminate shooter error), the gun is capable of producing a group of shots whose center points (center-to-center) fit into a circle, the average diameter of circles in several groups can be subtended by that amount of arc. For example, a "1 MOA rifle" should be capable, under ideal conditions, of repeatably shooting 1-inch groups at 100 yards. Most higher-end rifles are warrantied by their manufacturer to shoot under a given MOA threshold (typically 1 MOA or better) with specific ammunition and no error on the shooter's part. For example, Remington's M24 Sniper Weapon System is required to shoot 0.8 MOA or better, or be rejected from sale by quality control.
Rifle manufacturers and gun magazines often refer to this capability as "sub-MOA", meaning a gun consistently shooting groups under 1 MOA. This means that a single group of 3 to 5 shots at 100 yards, or the average of several groups, will measure less than 1 MOA between the two furthest shots in the group, i.e. all shots fall within 1 MOA. If larger samples are taken (i.e., more shots per group) then group size typically increases, however this will ultimately average out. If a rifle was truly a 1 MOA rifle, it would be just as likely that two consecutive shots land exactly on top of each other as that they land 1 MOA apart. For 5-shot groups, based on 95% confidence, a rifle that normally shoots 1 MOA can be expected to shoot groups between 0.58 MOA and 1.47 MOA, although the majority of these groups will be under 1 MOA. What this means in practice is if a rifle that shoots 1-inch groups on average at 100 yards shoots a group measuring 0.7 inches followed by a group that is 1.3 inches, this is not statistically abnormal.
The metric system counterpart of the MOA is the milliradian (mrad or 'mil'), being equal to one 1000th of the target range, laid out on a circle that has the observer as centre and the target range as radius. The number of milliradians on a full such circle therefore always is equal to 2 × × 1000, regardless the target range. Therefore, 1 MOA ≈ 0.2909 mrad. This means that an object which spans 1 mrad on the reticle is at a range that is in metres equal to the object's size in millimetres (e.g. an object of 100 mm subtending 1 mrad is 100 metres away). So there is no conversion factor required, contrary to the MOA system. A reticle with markings (hashes or dots) spaced with a one mrad apart (or a fraction of a mrad) are collectively called a mrad reticle. If the markings are round they are called mil-dots.
In the table below conversions from mrad to metric values are exact (e.g. 0.1 mrad equals exactly 10 mm at 100 metres), while conversions of minutes of arc to both metric and imperial values are approximate.
Human vision.
In humans, 20/20 vision is the ability to resolve a spatial pattern separated by a visual angle of one minute of arc.
A 20/20 letter subtends 5 minutes of arc total.
Materials.
The deviation from parallelism between two surfaces, for instance in optical engineering, is usually measured in arcminutes or arcseconds.
In addition, arcseconds are sometimes used in rocking curve (ω-scan) x ray diffraction measurements of high-quality epitaxial thin films.
Manufacturing.
Some measurement devices make use of arcminutes and arcseconds to measure angles when the object being measured is too small for direct visual inspection. For instance, a toolmaker's optical comparator will often include an option to measure in "minutes and seconds".


National Standard Examination in Junior Science

The National Standard Examination in Junior Science or NSEJS is an examination in
Science for secondary school students, usually conducted in the end of November. Organized by the Indian Association of Physics Teacher in association with Homi Bhabha Centre for Science Education (HBCSE), NSEJS is considered toughest Science exam on higher secondary level globally. The NSEJS is carried out every year since 1987 in English, Hindi & a few other Indian languages. More than 80,000 students from over 1,500 centres take part in these olympiads.
Eligibility.
Only Indian citizens born on or before December 31, 2007 and are students studying in Class X or lower as of November 30, 2017, can apply and appear for NSEJS 2017 − 2018. The student has to himself re-assure his eligibility. At any stage if the student is found to be not eligible for the exam, he/she may be disqualified from the program.
Only Indian citizens born on or before December 31, 2007 and are students studying in Class X or lower as of November 20, 2018, can apply and appear for NSEJS 2017 − 2018. The student has to himself re-assure his eligibility. At any stage if the student is found to be not eligible for the exam, he/she may be disqualified from the program.
Importance.
The top 300 students or so, with statewise quota, from this examination are selected to sit for the Indian National Junior Science Olympiad. The examination, with both a theory and an objective paper is held in the last week of January. The top 35 or so students are then called for an Orientation cum Selection Camp (OCSC), and the top 6 among all students are selected for the International Junior Science Olympiad.
Format.
Before 2014-15, The NSEJS comprised both multiple choice questions and subjective questions. Due to the large volume of participating students, all questions were not checked for all candidates; subjective questions were checked for only those candidates scoring above a certain minimum in the multiple choice questions. Multiple choice questions carried about 60% of the total weightage and were the crucial determinant for selection to the next stage.
The present format (from 2014-15 onwards) is composed entirely of 80 multiple-choice questions.
Fee.
The fee for the NSEJS is Rs. 180 ($15 for overseas candidates). Application for this examination is typically handled through the school/college to which the student is affiliated.
Qualifying for the Second Stage.
The basic objective of conducting this test is not focusing on merit but to involve as many students from the country to participate in the exam and try to show and expose their talent. Hence the selection to the stage examinations i.e. International Junior Science Olympiad Examinations (IJSO) is based on the following scheme.
Cutoff.
To be eligible to get to the next level, i.e. the second stage, it is necessary that a student scores at-least a Minimum Admissible Score (MAS) which is 50% of the maximum score. In the year 2019 the MAS was 99 and MI was 159
Proportional Representation Clause.
The maximum number of students that can get to Stage II (InJSO) in each subject is around 300. These any students are not selected only on the merit basis but also on proportionate basis. This proportion is decided on the base of the number of candidates who appeared for NSEJS in the previous year from that center in each State or Union Territory (UT). In case there is a tie at the last position, then all the students competing for the last position will be eligible to move to stage II. However it’s necessary that the selected students fulfill the eligibility clause laid out above. The total number to be selected from centers in each State for each subject will be displayed on the IAPT and HBCSE website.
Minimum Representation Clause.
Notwithstanding the proportional representation clause the number of students selected for IJSO from each State and UT must be at least one, provided that the eligibility clause is satisfied.
Merit Clause.
As stated above, approximately 300 students are to be selected for second stage. If this does not happen according to MAS, then after selection as per merit, the shortfall from 300 students will be selected based purely on merit without further consideration to proportional representation and minimum representation clauses. In the event of a tie at the last position in the list all students with the same marks at this position will qualify to appear for the Stage II examination.


Boris Beizer

Boris Beizer (1934-2018) was an American software engineer and author. He received his B.S. degree in physics from the City College of New York in 1956, an MS in Electrical Engineering (1963) and a PhD in computer science from the University of Pennsylvania in 1966. He wrote many books and articles on topics such as system architecture and software testing. His books "Software Testing Techniques" and "Software System Testing and Quality Assurance" are frequently consulted references on the subject. He directed testing for the FAA's Weather Message Switching Center and several other large communications systems. He was a speaker at many testing conferences and was also known for his seminars on testing. He consulted on software testing and quality assurance with many organizations throughout the world.
Personal life.
Boris Beizer was born in Brussels, Belgium. He emigrated to the United States in May, 1941.
List of Publications (partial).
Novels under pseudonym Ethan I. Shedley


7959 Alysecherri

7959 Alysecherri, provisional designation , is a bright, stony Hungaria asteroid from the inner regions of the asteroid belt, approximately 3 kilometers in diameter. It was discovered on 2 August 1994, by American astronomer Carl Hergenrother at Steward Observatory's Catalina Station on Mt Bigelow near Tucson, Arizona. The asteroid was named for the discoverer's wife, Alyse Cherri.
Orbit and classification.
The E-type asteroid is a member of the Hungaria family, which form the innermost dense concentration of asteroids in the Solar System. It orbits the Sun in the inner main-belt at a distance of 1.8–2.1 AU once every 2 years and 9 months (989 days). Its orbit has an eccentricity of 0.09 and an inclination of 19° with respect to the ecliptic. The first precovery was taken at Palomar Observatory in 1951, extending the asteroid's observation arc by 43 years prior to its discovery.
Physical characteristics.
A rotational lightcurve for this asteroid was obtained from photometric observations made by American astronomer Brian Warner at the U.S. Palmer Divide Observatory, Colorado, in July 2013. It gave a rotation period of hours with a brightness amplitude of 0.13 in magnitude (). The "Collaborative Asteroid Lightcurve Link" assumes an albedo of 0.30 and calculates a diameter of 3.05 kilometers with an absolute magnitude of 14.5.
Naming.
This minor planet is named after the maiden name of the discovering astronomer's wife, Alyse Cherri Smith. The official naming citation was published by the Minor Planet Center on 13 November 2008 ().


2606 Odessa

2606 Odessa, provisional designation , is a background asteroid from the central regions of the asteroid belt, approximately in diameter. It was discovered on 1 April 1976, by Soviet–Russian astronomer Nikolai Chernykh at the Crimean Astrophysical Observatory in Nauchnij, on the Crimean peninsula. The presumably metallic X- or M-type asteroid has an elongated shape and a rotation period of 8.24 hours. It was named for the Ukrainian city of Odessa.
Orbit and classification.
"Odessa" is a non-family asteroid from the main belt's background population. It orbits the Sun in the intermediate asteroid belt at a distance of 2.0–3.5 AU once every 4 years and 7 months (1,674 days; semi-major axis of 2.76 AU). Its orbit has an eccentricity of 0.26 and an inclination of 12° with respect to the ecliptic.
The body's observation arc begins with a precovery taken at Palomar Observatory in July 1954, near 22 years prior to its official discovery observation at Nauchnij.
Physical characteristics.
In the SMASS classification, "Odessa" is a Xk-subtype that transitions between the X- and K-type asteroids. It has also been characterized as an X-type by Pan-STARRS photometric survey, while it as an M-type asteroid according to the Wide-field Infrared Survey Explorer (WISE).
Rotation period and poles.
In 2008, two rotational lightcurves of "Odessa" were obtained from photometric observations at the Hunters Hill and Oakley Southern Sky observatories in Australia. Lightcurve analysis gave a well-defined rotation period of 8.2426 and 8.244 hours with a brightness amplitude of 0.80 and 0.72 magnitude, respectively, indicative for a non-spherical shape ().
In 2016, a modeled lightcurve gave a concurring sidereal period of 8.2444 hours using data from the Uppsala Asteroid Photometric Catalogue, the Palomar Transient Factory survey, and individual observers (such as above), as well as sparse-in-time photometry from the NOFS, the Catalina Sky Survey, and the La Palma surveys . The study also determined two spin axes of (25.0°, −81.0°) and (283.0°, −88.0°) in ecliptic coordinates (λ, β).
Diameter and albedo.
According to the survey carried out by the NEOWISE mission of NASA's WISE telescope, "Odessa" measures 15.91 kilometers in diameter and its surface has an albedo of 0.175, while the "Collaborative Asteroid Lightcurve Link" assumes a carbonaceous standard albedo of 0.057 and consequently calculates a larger diameter of 25.44 kilometers based on an absolute magnitude of 11.7.
Naming.
This minor planet was named after the Ukrainian black Sea port city of Odessa. The official naming citation was published by the Minor Planet Center on 1 December 1982 ().


838 Seraphina

838 Seraphina ("prov. designation": "or" ) is a dark and large background asteroid, approximately in diameter, located in the outer regions of the asteroid belt. It was discovered by German astronomer Max Wolf at the Heidelberg-Königstuhl State Observatory on 24 September 1916. The primitive P-type asteroid has a rotation period of 15.7 hours and is rather spherical in shape. Any reference to the origin of the asteroid's name is .
Orbit and classification.
"Seraphina" is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the outer asteroid belt at a distance of 2.5–3.3 AU once every 4 years and 11 months (1,802 days; semi-major axis of 2.9 AU). Its orbit has an eccentricity of 0.13 and an inclination of 10° with respect to the ecliptic. The body's observation arc begins with its official discovery observation at Heidelberg Observatory on 24 September 1916.
Naming.
Any reference of this minor planet name to a person or occurrence is unknown.
Unknown meaning.
Among the many thousands of named minor planets, "Seraphina" is , for which no official naming citation has been published. All of these asteroids have low numbers in between and and were discovered from 1876 up to the 1930s, predominantly by astronomers Auguste Charlois, Johann Palisa, Max Wolf and Karl Reinmuth.
Physical characteristics.
In the Tholen classification, "Seraphina" is a very dark, primitive P-type asteroid, that falls into the wider group of the carbonaceous C-Complex. In both the Tholen- and SMASS-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2), it is an X-type asteroid. P-type asteroids are common in the outer asteroid belt and among the Jupiter trojans.
Rotation period.
In November 2005, a rotational lightcurve of "Seraphina" was obtained from photometric observations by French amateur astronomer Raymond Poncy. Lightcurve analysis gave a rotation period of hours with a low brightness variation of magnitude, indicative of a rather spherical shape (). Other observations include a period of hours with an amplitude of magnitude by Richard Binzel from June 1984 (), and a period of hours with an amplitude of magnitude by the Spanish group of asteroid observers, OBAS, in November 2015 ().
In 2018, Czech astronomers Josef Ďurech and Josef Hanuš published a modeled lightcurve using photometric data from the "Gaia" spacecraft's second data release. It showed a sidereal period of hours (), and gave two spin axes at (18.0°, 4.0°) and (192.0°, 32.0°) in ecliptic coordinates (λ, β).
Diameter and albedo.
According to the surveys carried out by the Japanese Akari satellite, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), and the Infrared Astronomical Satellite IRAS, "Seraphina" measures (), () and () kilometers in diameter and its surface has an albedo of (), () and (), respectively. The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0427 and a diameter of 59.75 kilometers based on an absolute magnitude of 10.16. Alternative mean-diameter measurements published by the WISE team include (), () and () with corresponding albedos of (), () and ().
Two asteroid occultations of "Seraphina" gave a best-fit ellipse dimension of () and () for their respective observation on 5 February 2007 and on 20 July 2014. These timed observations are taken when the asteroid passes in front of a distant star. However, these two observations have received a poor quality rating.


Square (unit)

The square is an Imperial unit of area that is used in the construction industry in the United States and Canada, and was historically used in Australia. One square is equal to 100 square feet. Examples where the unit is used are roofing shingles, metal roofing, vinyl siding, and fibercement siding products. Some home builders use squares as a unit in floor plans to customers.
When used in reference to material that is applied in an overlapped fashion, such as roof shingles or siding, a square refers to the amount of material needed to cover 100 square feet when installed according to a certain lap pattern. For example, for a shingle product designed to be installed so that each course has 5" of exposure, a square would actually consist of more than 100 square feet of shingles in order to allow for overlapping of courses to yield the proper exposed surface.
Buildings in Australia no longer use the square as a unit of measure, and has been replaced by square metres. The measurement was often used by estate agents to make the building sound larger as the measure includes the areas outside under the eaves, and so cannot be directly compared to the internal floor area. Residential buildings in the state of Victoria, Australia are sometimes still advertised in squares.
Conversions.
1 square equals


2930 Euripides


764 Gedania

764 Gedania ("prov. designation:" "or" ) is a large background asteroid from the outer regions of the asteroid belt, approximately in diameter. It was discovered on 26 September 1913, by German astronomer Franz Kaiser at the Heidelberg-Königstuhl State Observatory in southwest Germany. The carbonaceous C-type asteroid has a rotation period of 24.98 hours. It was named after the Polish city of Gdańsk where the discoverer was an assistant at the observatory during the 1920s.
Orbit and classification.
"Gedania" is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements. It orbits the Sun in the outer asteroid belt at a distance of 2.9–3.5 AU once every 5 years and 9 months (2,092 days; semi-major axis of 3.2 AU). Its orbit has an eccentricity of 0.09 and an inclination of 10° with respect to the ecliptic. The body's observation arc begins with its first observation as at Heidelberg Observatory in November 1902, almost 11 years prior to its official discovery observation by Franz Kaiser.
Naming.
This minor planet was named after the Latin name of the city of Gdańsk, Poland (formerly Free City of Danzig) where the discoverer, Franz Kaiser (1891–1962), was an assistant at the observatory during the early 1920s. The official naming citation was mentioned in "The Names of the Minor Planets" by Paul Herget in 1955 (). Asteroid 1419 Danzig was also named by its German name for the city of Gdańsk.
Physical characteristics.
In the Tholen classification, "Gedania" is a common carbonaceous C-type asteroid. It has also been classified as an hydrated Ch-type and as a Caa type in the Tholen- and SMASS-like taxonomic variant of the Small Solar System Objects Spectroscopic Survey (S3OS2).
Rotation period.
In February 2006, a rotational lightcurve of "Gedania" was obtained from photometric observations by collaborating astronomers Roberto Crippa, Federico Manzini , René Roy, Donn Starkey, Raoul Behrend and Laurent Bernasconi. Lightcurve analysis gave a rotation period of hours with a brightness variation of magnitude (). Observations by Aznar, Brinsfield and Pál, gave an alternative period determination of , and hours, respectively ().
Diameter and albedo.
According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer and the Japanese Akari satellite, "Gedania" measures , and kilometers in diameter and its surface has an albedo of , and , respectively. The "Collaborative Asteroid Lightcurve Link" derives an albedo of 0.0754 and a diameter of 58.18 kilometers based on an absolute magnitude of 9.6. An alternative mean-diameter measurement published by the WISE team gave () with corresponding albedo of (). On 5 February 2006, an asteroid occultation of "Gedania" gave a best-fit ellipse dimension of (), with a poor quality rating of 1. These timed observations are taken when the asteroid passes in front of a distant star.


Mildred Barnard

Mildred Macfarlan Barnard (also known as Mildred Macfarlan Prentice, 5 August 1908 – 9 March 2000) was an Australian biometrician, mathematician and statistician.
Early life and education.
Barnard was born in Melbourne on 5 August 1908. Her mother, Jessie Margaret Barnard, helped found the Federal Territory War Food Fund. Her father, Robert James Allman Barnard, became a foundation professor of mathematics at the Royal Military College, Duntroon near Canberra, where the family moved in 1911. They returned to Melbourne in the 1920s, when Barnard's father took a position as senior lecturer at the University of Melbourne.
Barnard entered the University of Melbourne in 1927. She won a Dixson Scholarship in 1930, the same year that she completed a B.A. with honours in mathematics. She added a B.S. in physics in 1931 and an M.S. in 1932. Her master's thesis concerned the continuum mechanics of a cracked thin plate, and was supervised by John Henry Michell.
In search of a subject that would bring her into more contact with other people, and discouraged by the job prospects for mathematicians and physicists in Australia, Barnard shifted her interests to biometrics. She began her doctoral studies in statistics with Ronald Fisher in the Galton Laboratory at University College London in 1934. She published three papers in this period, on craniometry, factorial experiments, and environmental statistics, and completed her Ph.D. in 1936.
Career and later life.
After completing her education, Barnard returned to Australia and became an assistant biometrician in the Division of Forest Products of the Council for Scientific and Industrial Research, beginning in 1936. Although centred at Melbourne, her position also involved spending time in Canberra and Sydney. While at CSIR she worked with Betty Allan. Topics that Barnard researched were the 'holding power of coach screws and the serviceability of railway sleepers and telegraph poles'. In the normal course of events, she would have lost the position when she married in 1939, but the outbreak of World War II, and the need for wood in airplanes, caused greater demands on her office, so her resignation was delayed until the birth of her first child in 1941.
While raising a family, she lectured part-time at the University of Melbourne until she and her family moved to Brisbane, where her husband found a position as professor of electrical engineering at the University of Queensland. She continued her part-time lecturing there and, in 1970, she was appointed as lecturer in mathematical statistics at the University of Queensland.
In 1972 she became the first Chairwoman (1972) of the Brisbane Branch of the International Biometric Society, Australasian Region.
She died in Brisbane on 9 March 2000.
Book.
Barnard's book "Elementary Statistics for Use in Timber Research" (with Neil Ditchburn, CSIRO, 1956) was published after being printed twice for CSIRO use.


EExam

An eExam (e-exam) is a timed, supervised, summative assessment conducted using each candidate's own computer running a standardised operating system.Such examinations have advantages over paper-based exams, and can include new multi-media, simulation and software test items which give higher validity in respect of professional work practice.
Electronic exams offer benefits such as ease of marking, reduced need to read illegible handwriting, saving of time and raw materials and reduced logistical overheads.
Challenges.
Many innovations face reactionary challenges in the social, political and technical spheres. Objections focus on the unreliability of computer equipment or the potential for cheating. Some 'hacks' against eExams use cooling of the computer RAM to 0 degrees Celsius, when the contents can be preserved for about 45 seconds. This is irrelevant if the exam question paper is published after the assessment and open source software is used (since the material is put in the public domain anyway). These criticisms have been answered by a risk tree comparison with paper-based examinations, finding the typing and handwriting in examinations are similarly secure.
The challenges of e-exams are: usability issues during the exam, increased stress level due to unfamiliarity with e-exam systems and inadequate functionality.