Longwood, Saint Helena

Longwood is a settlement and a district of the British island of Saint Helena, where Napoleon was exiled from 1815 until his death on 5 May 1821. France owns the land around Napoleon's original grave, but the United Kingdom retains full sovereignty.

In 2008 it had a population of 715, compared to a population of 960 in 1998. The area of the district is 33.4 km 2. The large district (second only to Blue Hill) includes the settlement of Hutt's Gate, with its St Matthew's church. The district also contains the island's only existing golf course. The district contains Prosperous Bay Plain, which is where the proposed Saint Helena Airport would be sited.

There is a weather recording station in the Longwood district. Readings of temperature, air pressure and visibility are automatically read and communicated every 3 hours.

Observatories
On leaving the University of Oxford, in 1676, Edmond Halley visited Saint Helena and set up an observatory with a 24 ft aerial telescope with the intention of studying stars from the Southern Hemisphere. The site of this telescope is near St Matthew's church in the district. The 680m high hill there is named for him and is called Halley's Mount.

Halley's Observatory was in use 1677-1678. Having returned to England in 1678, Halley published Catalogus Stellarum Australium in 1679, which included details of 341 southern stars. These additions to present-day star maps earned him comparison with Tycho Brahe. Halley subsequently was awarded with his Masters from Oxford and Fellowship of the Royal Society.

In 1686 Halley published the second part of the results from his Helenian expedition, being a paper and chart on trade winds and monsoons. In this he identified solar heating as the cause of atmospheric motions. He also established the relationship between barometric pressure and height above sea level. His charts were an important contribution to the emerging field of information visualization.

In the 19th/early 20th centuries, an observatory (in use 1840-1849) was situated in Longwood village and two further observatories were erected in the Hutt's Gate area: one in use 1892-1924 and the second in use 1925-1975.