Henry Andrews was born in the village of Frieston

Frieston

Frieston forms the southern end of the village of Caythorpe in the South Kesteven district of Lincolnshire, England.It is part of the civil parish of Caythorpe. Local government has been arranged in this way since the reorganisation of 1 April 1974, which resulted from the 1972 Local Government...

, near Grantham

Grantham

Grantham is a market town within the South Kesteven district of Lincolnshire, England. It bestrides the East Coast Main Line railway , the historic A1 main north-south road, and the River Witham. Grantham is located approximately south of the city of Lincoln, and approximately east of Nottingham...

, Lincolnshire

Lincolnshire

Lincolnshire is a county in the east of England. It borders Norfolk to the south east, Cambridgeshire to the south, Rutland to the south west, Leicestershire and Nottinghamshire to the west, South Yorkshire to the north west, and the East Riding of Yorkshire to the north. It also borders...

, England. He established a reputation as an accomplished mathematician

Mathematician

A mathematician is a person whose primary area of study is the field of mathematics. Mathematicians are concerned with quantity, structure, space, and change....

 and astronomer

Astronomer

An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...

.

For 43 years he worked in his spare time as 'Compiler of the tables detailing the movement of the planets' for Old Moore's Almanac

Old Moore's Almanac

Old Moore's Almanac is an almanac which has been published annually in Ireland since 1764.It was originally written and published by Theophilus Moore who ran a classical academy at Milltown which was then a village near Dublin....

. His day job was Calculator to the Board of Longitude

Board of Longitude

The Board of Longitude was the popular name for the Commissioners for the Discovery of the Longitude at Sea. It was a British Government body formed in 1714 to administer a scheme of prizes intended to encourage innovators to solve the problem of finding longitude at sea.-Origins:Navigators and...

. He had also set up a boarding school

Boarding school

A boarding school is a school where some or all pupils study and live during the school year with their fellow students and possibly teachers and/or administrators. The word 'boarding' is used in the sense of "bed and board," i.e., lodging and meals...

 which taught trigonometry

Trigonometry

Trigonometry is a branch of mathematics that studies triangles and the relationships between their sides and the angles between these sides. Trigonometry defines the trigonometric functions, which describe those relationships and have applicability to cyclical phenomena, such as waves...

 and navigation

Navigation

Navigation is the process of monitoring and controlling the movement of a craft or vehicle from one place to another. It is also the term of art used for the specialized knowledge used by navigators to perform navigation tasks...

 as extra subjects, as well as running a shop which sold books, stationery, barometer

Barometer

A barometer is a scientific instrument used in meteorology to measure atmospheric pressure. Pressure tendency can forecast short term changes in the weather...

s, thermometers, and philosophical and mathematical instruments

Measuring instrument

In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item...

. He was a well-respected professional and valued advisor to the Rev'd Nevil Maskelyne

Nevil Maskelyne

The Reverend Dr Nevil Maskelyne FRS was the fifth English Astronomer Royal. He held the office from 1765 to 1811.-Biography:...

, the Astronomer Royal

Astronomer Royal

Astronomer Royal is a senior post in the Royal Household of the Sovereign of the United Kingdom. There are two officers, the senior being the Astronomer Royal dating from 22 June 1675; the second is the Astronomer Royal for Scotland dating from 1834....

.

Andrews predicted the annular solar eclipse in 1791:

To the north of Scotland it will be a very great eclipse; but nowhere total on account of the apparent diameter of the sun. The spectators will be entertained with a beautiful annulus, or ring of light encompassing the opaque body of the Moon on every side. This eclipse begins with the rising sun in the back settlements of Carolina and Virginia, from whence it traverses Hudson's Bay, north-easterly towards the coast of Greenland, Iceland and Lapland, and the northern coast of Great Tartary where this phenomenon will end and quit the earth with the setting sun.