• Home
• Brief History
• The Greenwich Meridian
•  
• Greenwich (1675–1958)
• Herstmonceux (1948–1990)
• Cambridge (1990–1998)
• Outstations (1822–1971)…
  • – Chingford (1822–1924)
  • – Deal (1864–1927)
  • – Abinger (1923–1957)
  • – Bristol & Bradford on Avon    (1939–1948)
  • – Bath (1939–1949)
  • – Hartland (1955–1967)
  • – Cape of Good Hope    (1959–1971)
•  
• Administration…
  • – Funding
  • – Governance
  • – Inventories
  • – Pay
  • – Regulations
  • – Royal Warrants
•  
• Contemporary Accounts
• People
• Publications
• Science
• Technology
• Telescopes
• Chronometers
• Clocks & Time
• Board of Longitude
•  
• Libraries & Archives
• Visit
•  
• Search

Solar eclipses observed by the Observatory staff at Greenwich and elswhere (1675-1998)

page under construction

Between 1675 when the Observatory was founded and 1998 when it was closed, just five total eclipses of the Sun were visible from the land mass of Great Britain. They took place in 1699, 1715, 1724, 1927 and 1954. Only that of 1715 was potentially visible as a total eclipse at the Observatory. During the same time period, there were no annular eclipses visible from Greenwich.

From 1675 until 1842 when Airy travelled to Turin to observe a total eclipse, solar eclipses were only ever observed from Greenwich. Under Airy, there were a total of four overseas expeditions. Further expeditions continued under the next three Astronomers Royal, Christie (7), Dyson (8 including one in the UK), and Spencer Jones (5).

Of the many partial eclipses that could have been observed from Greenwich, the great majority went unobserved. From Maskelyne's time onwards, any that were, have been recorded in the published volumes of Greenwich Observations. Many (but not all) were also mentioned in the Reports of the Astronomer Royal which were published for all the years from 1836 to 1964.

What is not currently known is how many of the eclipses that were planned to be observed at Greenwich were not observed because of the weather. These were not normally reported on. An analysis of the published observations made on the same day at Greenwich may give some sort of indication of the weather at the time of the unobserved eclipses. Fred Espenak has produced an eclipse calculator for any latitude, longitude and elevation. The calculator for places in Europe can be found here.

Below is a provisional list of eclipses observed by the Greenwich astronomers between 1675 and 1990 and those observed at the Cape between 1959 and 1971 (when it was under the control of Greenwich). In due course, more information and links will be added together with any additional eclipses for which observations are found.

Dates and timings

Since 1752, the UK has been using the Gregorian Calendar. Prior to that date, the Julian Calendar was in use. The parenthesis in the Date column are the Gregorian equivalents. The other thing to take into account is whether the Greenwich astronomers recorded their observations and the date and times of eclipses in terms of sidereal time as opposed to either local apparent solar time of local mean solar time as the astronomical day which began (at midday) twelve hours later than the civil day of the same date (which began at midnight). Although the published transit observations were given in terms of the astronomical day until the start of 1925, some other observations were given in terms of civil time from a much earlier date. It is currently unclear what the pattern of reporting was with eclipses. It is hoped to produces some sort of analysis at a later date.

It should be noted that the data generated by the Espenak calculator gives all dates in terms of the Gregorian Calendar and all timings in terms of the civil day.

The Nautical Almanac

The Nautical Almanac contained information about upcoming eclipse from the first volume (for the year 1767) onwards. From the volume for the year 1834 onwards, they also contained maps showing from where on the earth total and annular eclipses could be seen.

Key to the table below

Type:         T = Total, A = Annular, H = Hybrid, P = Partial. Lower case as occurred at observing location

Time:        This column shows the instruments used for timing the eclipse:
                 Oi = observatory instruments, To = Tompion clock in the Octagon Room
                 T = transit clock, C = chronometer,
                 PC = Pocket chronometer, R = radio time signal,  TC = tape chronograph, X = no timings recorded

Obsc:        Maximum amount obscured at viewing site (from Espenak's calculator)

Succ?:      F = complete failure (applies only to expeditions away from Greenwich