Abul-Qâsem Ferdowsi Tusi, or just Ferdowsi was a Persian poet and the author of Shahnameh, one of the world's longest epic poem created by a single poet, the national epic of Greater Iran. Ferdowsi is celebrated as the most influential figure in Persian literature and one of the greatest in the history of literature. Except for his kunya and his laqab, nothing is known with any certainty about his full name. From an early period on, he has been referred to by different additional names and titles, the most common one being حکیم / Ḥakīm. Based on this, his full name is given in Persian sources as حکیم ابوالقاسم فردوسی توسی / Ḥakīm Abu'l-Qāsim Firdowsī Țusī. Due to the non-standardized transliteration from Persian into English, different spellings of his name are used in English works, including Firdawsi, Firdosi, etc; the Encyclopaedia of Islam uses the spelling Firdawsī, based on the standardized transliteration method of the German Oriental Society. The Encyclopædia Iranica, which uses a modified version of the same method, gives the spelling Ferdowsī.

In both cases, the -ow and -aw are to be pronounced as a diphthong, reflecting the original Arabic and the early New Persian pronunciation of the name. The modern Tajik transliteration of his name in Cyrillic script is Ҳаким Абулқосим Фирдавсӣ Тӯсӣ. Ferdowsi was born into a family of Iranian landowners in 940 in the village of Paj, near the city of Tus, in the Khorasan region of the Samanid Empire, located in the present-day Razavi Khorasan Province of northeastern Iran. Little is known about Ferdowsi's early life; the poet had a wife, literate and came from the same dehqan class. He had a son, who died at the age of 37, was mourned by the poet in an elegy which he inserted into the Shahnameh. Ferdowsi belonged to the class of dehqans; these were landowning Iranian aristocrats who had flourished under the Sassanid dynasty and whose power, though diminished, had survived into the Islamic era which followed the Islamic conquests of the 7th century. The dehqans were attached to the pre-Islamic literary heritage, as their status was associated with it.

Thus they saw it as their task to preserve the pre-Islamic cultural traditions, including tales of legendary kings. The Islamic conquests of the 7th century brought gradual linguistic and cultural changes to the Iranian Plateau. By the late 9th century, as the power of the caliphate had weakened, several local dynasties emerged in Greater Iran. Ferdowsi grew up in Tus, a city under the control of one of these dynasties, the Samanids, who claimed descent from the Sassanid general Bahram Chobin; the Samanid bureaucracy used the New Persian language, used to bring Islam to the Eastern regions of the Iranian world and supplanted local languages, commissioned translations of Pahlavi texts into New Persian. Abu Mansur Muhammad, a dehqan and governor of Tus, had ordered his minister Abu Mansur Mamari to invite several local scholars to compile a prose Shahnameh, completed in 1010. Although it no longer survives, Ferdowsi used it as one of the sources of his epic. Samanid rulers were patrons of such important Persian poets as Rudaki and Daqiqi, Ferdowsi followed in the footsteps of these writers.

Details about Ferdowsi's education are lacking. Judging by the Shahnameh, there is no evidence he knew either Pahlavi, it is possible. He began work on the Shahnameh around 977, intending it as a continuation of the work of his fellow poet Daqiqi, assassinated by a slave. Like Daqiqi, Ferdowsi employed the prose Shahnameh of ʿAbd-al-Razzāq as a source, he received generous patronage from the Samanid prince Mansur and completed the first version of the Shahnameh in 994. When the Turkic Ghaznavids overthrew the Samanids in the late 990s, Ferdowsi continued to work on the poem, rewriting sections to praise the Ghaznavid Sultan Mahmud. Mahmud's attitude to Ferdowsi and how well he rewarded the poet are matters which have long been subject to dispute and have formed the basis of legends about the poet and his patron; the Turkic Mahmud may have been less interested in tales from Iranian history than the Samanids. The sections of the Shahnameh have passages which reveal Ferdowsi's fluctuating moods: in some he complains about old age, poverty and the death of his son.

Ferdowsi completed his epic on 8 March 1010. Nothing is known with any certainty about the last decade of his life. Ferdowsi was buried in his own garden, burial in the cemetery of Tus having been forbidden by a local cleric. A Ghaznavid governor of Khorasan constructed a mausoleum over the grave and it became a revered site; the tomb, which had fallen into decay, was rebuilt between 1928 and 1934 by the Society for the National Heritage of Iran on the orders of Rezā Shāh, has now become the equivalent of a national shrine. According to legend, Sultan Mahmud of Ghazni offered Ferdowsi a gold piece for every couplet of the Shahnameh he wrote; the poet agreed to receive the money as a lump sum. He planned to use it to rebuild the dykes in his native Tus. After thirty years of work, Ferdowsi finished his masterpiece; the sultan prepared to give him one for every couplet, as agreed. However, the courtier whom

Celestial coordinate system

In astronomy, a celestial coordinate system is a system for specifying positions of satellites, stars and other celestial objects. Coordinate systems can specify an object's position in three-dimensional space or plot its direction on a celestial sphere, if the object's distance is unknown or trivial; the coordinate systems are implemented in either rectangular coordinates. Spherical coordinates, projected on the celestial sphere, are analogous to the geographic coordinate system used on the surface of Earth; these differ in their choice of fundamental plane, which divides the celestial sphere into two equal hemispheres along a great circle. Rectangular coordinates, in appropriate units, are the cartesian equivalent of the spherical coordinates, with the same fundamental plane and primary direction; each coordinate system is named after its choice of fundamental plane. The following table lists the common coordinate systems in use by the astronomical community; the fundamental plane divides the celestial sphere into two equal hemispheres and defines the baseline for the latitudinal coordinates, similar to the equator in the geographic coordinate system.

The poles are located at ±90° from the fundamental plane. The primary direction is the starting point of the longitudinal coordinates; the origin is the zero distance point, the "center of the celestial sphere", although the definition of celestial sphere is ambiguous about the definition of its center point. The horizontal, or altitude-azimuth, system is based on the position of the observer on Earth, which revolves around its own axis once per sidereal day in relation to the star background; the positioning of a celestial object by the horizontal system varies with time, but is a useful coordinate system for locating and tracking objects for observers on Earth. It is based on the position of stars relative to an observer's ideal horizon; the equatorial coordinate system is centered at Earth's center, but fixed relative to the celestial poles and the March equinox. The coordinates are based on the location of stars relative to Earth's equator if it were projected out to an infinite distance.

The equatorial describes the sky as seen from the Solar System, modern star maps exclusively use equatorial coordinates. The equatorial system is the normal coordinate system for most professional and many amateur astronomers having an equatorial mount that follows the movement of the sky during the night. Celestial objects are found by adjusting the telescope's or other instrument's scales so that they match the equatorial coordinates of the selected object to observe. Popular choices of pole and equator are the older B1950 and the modern J2000 systems, but a pole and equator "of date" can be used, meaning one appropriate to the date under consideration, such as when a measurement of the position of a planet or spacecraft is made. There are subdivisions into "mean of date" coordinates, which average out or ignore nutation, "true of date," which include nutation; the fundamental plane is the plane of the Earth's orbit, called the ecliptic plane. There are two principal variants of the ecliptic coordinate system: geocentric ecliptic coordinates centered on the Earth and heliocentric ecliptic coordinates centered on the center of mass of the Solar System.

The geocentric ecliptic system was the principal coordinate system for ancient astronomy and is still useful for computing the apparent motions of the Sun and planets. The heliocentric ecliptic system describes the planets' orbital movement around the Sun, centers on the barycenter of the Solar System; the system is used for computing the positions of planets and other Solar System bodies, as well as defining their orbital elements. The galactic coordinate system uses the approximate plane of our galaxy as its fundamental plane; the Solar System is still the center of the coordinate system, the zero point is defined as the direction towards the galactic center. Galactic latitude resembles the elevation above the galactic plane and galactic longitude determines direction relative to the center of the galaxy; the supergalactic coordinate system corresponds to a fundamental plane that contains a higher than average number of local galaxies in the sky as seen from Earth. Conversions between the various coordinate systems are given.

See the notes before using these equations. Horizontal coordinates A, azimuth a, altitude Equatorial coordinates α, right ascension δ, declination h, hour angle Ecliptic coordinates λ, ecliptic longitude β, ecliptic latitude Galactic coordinates l, galactic longitude b, galactic latitude Miscellaneous λo, observer's longitude ϕo, observer's latitude ε, obliquity of the ecliptic θL, local sidereal time θG, Greenwich sidereal time h = θ L − α or h = θ G + λ o − α α = θ L − h or α = θ G + λ o − h The classical equations, derived from spherical trigonometry, for

Crown Buildings, Cathays Park

The Crown Buildings, which are known as the Cathays Park Buildings, are the Welsh Government's main offices in Cardiff, Wales. The buildings were used by the Welsh Office and are situated in Cathays Park; the complex consists of Cathays Park 1 and Cathays Park 2, joined by two skybridges. In 1914 foundations were laid for an imposing neoclassical building on this site housing Welsh Government Offices, to a design by R. J. Allison, architect to the Office of Works. Work soon did not resume for twenty years. In 1934–8, the block now known as Cathays Park 1 was built by P. E. Hanton, as offices for the Welsh Board of Health, it is a three-storey building in the Stripped Classical style, with 3,599 m2 of floorspace. It has an attic and a basement. Cathays Park 2 is a five-storey office building with 34,305 m2 of floorspace, including an underground car park and a central atrium housing a cafe for the office staff; the Encyclopaedia of Wales describes CP2, completed in 1979, as conveying an impression of "bureaucracy under siege".

The historian John Davies, regarded the complex as being "splendid". The sky bridge between Cathays Park 1 and 2'the link' has been the subject of some discussion amongst staff based in the building. People have reported an eerie feeling, a general sense of something "unworldly" with people catching fleeting glimpses out of the corner of their eye which had led to rumours of the area being haunted. In 1968, Cathays Park 1 was damaged by a bomb explosion, the second in the area in under 12 months following a previous attack on the nearby Temple of Peace. Aerial photograph of Cathays Park The National Assembly for Wales – A Home For the Assembly