Woodcut showing the 16th century astronomical clock of Uppsala Cathedral, with two clockfaces, one with Arabic and one with Roman numerals.

However, his astronomical clock and rotating armillary sphere still relied on the use of flowing water ( i. e. hydraulics ), while European clockworks of the following centuries shed this old method for a more efficient driving power of weights, in addition to the escapement mechanism.

Other early versions of mechanical devices used to perform one or another type of calculations include the planisphere and other mechanical computing devices invented by Abū Rayhān al-Bīrūnī ( c. AD 1000 ); the equatorium and universal latitude-independent astrolabe by Abū Ishāq Ibrāhīm al-Zarqālī ( c. AD 1015 ); the astronomical analog computers of other medieval Muslim astronomers and engineers ; and the astronomical clock tower of Su Song ( c. AD 1090 ) during the Song Dynasty.

Many leading scientists including Newton and Huygens doubted that such a clock could ever be built and had more optimism for astronomical observations ( such as the Method of Lunar Distances ).

He invented the world's first water-powered armillary sphere, to represent astronomical observation ; improved the inflow water clock by adding another tank ; and invented the world's first seismometer, which discerned the cardinal direction of an earthquake away.

* 1077: Chinese official Su Song is sent on a diplomatic mission to the Liao Dynasty and discovers that the Khitan calendar is more mathematically accurate than the Song calendar ; Emperor Zhezong later sponsors Su Song's astronomical clock tower in order to compete with Liao astronomers.

* 1094: the astronomical clock tower of Kaifeng, China — engineered by the official Su Song — is completed.

* 1094 – The Chinese mechanical engineer and astronomer Su Song incorporates an escapement mechanism and the world's first known chain drive to operate the armillary sphere, the astronomical clock, and the striking clock jacks of his clock tower in Kaifeng.

* The Chinese polymath statesman and scientist Su Song has the successful pilot model for his astronomical clock tower constructed in Kaifeng, China.

* Zhang Sixun, a Chinese astronomer and engineer, employs the use of liquid mercury in order for the escapement mechanism of his astronomical clock to function and for metal parts not to rust by using hydraulics ( water ) or to freeze in winter.

The invention in 1955 of the caesium atomic clock has led to the replacement of older and purely astronomical time standards, for most practical purposes, by newer time standards based wholly or partly on atomic time.

The oldest known Huygens style pendulum clock is dated 1657 and can be seen at the Museum Boerhaave in Leiden which also shows an important astronomical clock owned and used by Huygens.

The Gros Horloge is an astronomical clock dating back to the 16th century, though the movement is considerably older ( 1389 ).

The gatehouse to the second, inner court was adorned in 1540 with an early example of a post-Copernican astronomical clock.

He also promoted groundbreaking science and technological innovations by supporting such works as the astronomical clock tower designed and built by the engineer Zhang Sixun.

An interior diagram of the Astronomical clock | astronomical clocktower of Kaifeng featured in Su Song's book, written by 1092 and published in printed form by the year 1094.

Su Song was best known for his horology treatise written in 1092, which described and illustrated in great detail his hydraulic-powered, tall astronomical clock tower built in Kaifeng.

The clock tower featured large astronomical instruments of the armillary sphere and celestial globe, both driven by an early intermittently working escapement mechanism ( roughly two centuries before the discrete verge escapement of true mechanical clocks appeared in medieval clockworks ).

* 1206-Al-Jazari invented his largest astronomical clock, the " castle clock ", which is considered to be the first programmable analog computer.

* 1577-80-Taqi al-Din invents a mechanical astronomical clock that measures time in seconds, one of the most important innovations in 16th-century practical astronomy, as previous clocks were not accurate enough to be used for astronomical purposes.

Although Strabo cited the antique Greek astronomers Eratosthenes and Hipparchus, acknowledging their astronomical and mathematical efforts towards geography, he claimed that a descriptive approach was more practical, such that his works were designed for statesmen who were more anthropologically than numerically concerned with the character of countries and regions.

It was heliocentric and used as a mechanical calculator designed to calculate astronomical positions.

The Antikythera mechanism was an analog computer from 150 – 100 BC designed to calculate the positions of astronomical objects.

At first mechanical astronomical clocks were influenced by the astrolabe ; in many ways they could be seen as clockwork astrolabes designed to produce a continual display of the current position of the sun, stars, and planets.

Thom and his father made other controversial contentions, for example, that Brodgar and the burial mounds that surround it were designed specifically as backsights for astronomical observations of the Moon.

The Antikythera mechanism is an example of a very early and intricate geared device, designed to calculate astronomical positions.

It was, on the one hand, designed to carry out long-term research into the problems of living in space and a variety of astronomical, biological and Earth-resources experiments, and on the other hand this civilian program was used as a cover for the highly secretive military Almaz stations, which flew as well under the Salyut designation.

The Antikythera mechanism ( or ) is an ancient analog computer designed to calculate astronomical positions.

In professional astronomical research, photography revolutionized the field, with long time exposures recording hundreds of thousands of new stars and nebulae that were invisible to the human eye, leading to specialized and ever larger optical telescopes that were essentially big " cameras " designed to collect light to be recorded on film.

Direct astrophotography had an early role in sky surveys and star classification but over time it has given way to more sophisticated equipment and techniques designed for specific fields of scientific research, with film ( and later astronomical CCD cameras ) becoming just one of many forms of sensor.

Despite this, a first light is always a moment of great excitement, both for the people who designed and built the telescope, and for the astronomical community.

The Antikythera mechanism from 150 – 100 BC was designed to calculate the positions of astronomical objects.

The Laser Interferometer Space Antenna ( LISA ) is a proposed space mission concept designed to detect and accurately measure gravitational waves from astronomical sources.

This type of mount is used in Transit telescopes, designed for precision astronomical measurement.

The search engine is tailor-made for searching astronomical abstracts, and the engine and its user interface assume that the user is well-versed in astronomy and able to interpret search results which are designed to return more than just the most relevant papers.

) He designed sundials, published manuals for astronomical instruments and crafted volvelles (" Apian wheels "), measuring instruments useful for calculating time and distance for astronomical and astrological applications.

* Photo-polarimeter ( ISOPHOT )-An instrument designed to measure the amount of infrared radiation emitted from an astronomical object.

The observatory also houses a team of astronomical researchers and scientists from CIT, most of which are engaged in the development of new technologies designed for searching for planets around distant stars, a project known as the Planet Search Programme.

In Song China, an astronomical clock tower was designed by Su Song and erected at Kaifeng in 1088, featuring a liquid escapement mechanism.

He has designed and built spectrometers, detectors, and imaging systems, and made numerous spacecraft and ground-based astronomical observations.

Grubb, son of the Grubb telescope building family in Dublin, designed the observatory and built the astronomical instruments for the structure.

The torquetum or turquet is a medieval astronomical instrument designed to take and convert measurements made in three sets of coordinates: Horizon, equatorial, and ecliptic.

If the Serpent Mound were designed to sight both solar and lunar arrays, it would be significant as the consolidation of astronomical knowledge into a single symbol.