Name Acronym Date Type* Location Association
(*G–Governmental; I–Institutional; Pr–Private; Pu–Public; S–School & U–University)
| Macfarlane Observatory | MOUG | 1757-1844 | U | Lanarkshire | Macfarlane, Alexander |
| Maclear’s Observatory | MOB | 1828-1833 | Pr | Bedfordshire | Maclear, Thomas |
| Magdalen College Observatory | MCO | 1857-1902 | U | Oxfordshire | Daubeny, Charles |
| Maghull Observatory | see Roberts’s Maghull Observatory [RMO] | ||||
| Makerstoun Observatory | see Brisbane’s Makerstoun Observatory [BOMH] | ||||
| Malcolm Parry Observatory | MPO | 2012- | S | Nottinghamshire | The Long Eaton School |
| Maldwyn’s Observatory | MO | 1960s | Pr | Anglesey | Maldwyn Parry |
| Manchester Physics Institute Observatory | MPIO | 1904- ? | U | Lancashire | Bazley, Sir Thomas; Manchester Victoria University; Manchester University |
| Marina Towers Observatory | MTO | 1993-2010 | I | Glamorgan | Swansea Astronomical Society (SwAS) |
| Marischal College Observatory | MCOA | 1798-1838 | U | Aberdeenshire | Copland, Patrick; Marischal College |
| Marischal College Observatory | see Castle Hill Observatory [CHOA] | ||||
| Markree Observatory | MaO | 1831-1902 | Pr | Sligo | Cooper, Edward Henry; Cooper, Edward Joshua; Doberck, Anna Nielsin; Doberck, William; Henkel, Frederick William |
| Markwick’s Observatory | see Markwick’s Boscombe Observatory [MaOB] | ||||
| see Markwick’s Devonport Observatory [MaOD] | |||||
| see Markwick’s West Moors Observatory [MaOWM] | |||||
| Markwick’s Devonport Observatory | MaOD | 1898-1903 | Pr | Devon | Markwick, E.E. |
| Markwick’s Boscombe Observatory | MaOB | 1905-1914 | Pr | Hampshire | Markwick, E.E. |
| Markwick’s West Moors Observatory | MaOWM | 1919-1926 | Pr | Dorset | Markwick, E.E. |
| Marlborough College Blackett Observatory | MCBO | 1935- | S | Wiltshire | Knox-Shaw, Harold; Marlborough College |
| Marlborough House Observatory | MHOL | 1770-1772 c. | Pr | County of London | Spencer, George, 4th duke of Marlborough |
| Mathematical Tower Observatory | MTOO | 1619-1772 | U | Oxfordshire | Greaves,John; Ward; Bradley, James; Hornsby, James |
| Maw’s Observatory | See Maw’s Kensington Observatory [MOKL] | ||||
| See Maw’s Outwood Observatory [MOO] | |||||
| Maw’s Kensington Observatory | MOKL | 1887-1924 | Pr | County of London | Maw, William Henry |
| Maw’s Outwood Observatory | MOO | 1896-1927 | Pr | Surrey | Maw, William Henry |
| May’s Observatory | MaO | 1840s-1850s | Pr | Suffolk | May, Charles |
| McClean’s Ferncliffe Observatory | MCOF | 1875-1883 | Pr | Kent | McClean,Frank |
| McClean’s Rushall Observatory | MCOR | 1884-1890s | Pr | Kent | McClean,Frank |
| Mee’s Observatory | MeO | 1890s-1900 | Pr | Glamorgan | Mee, Arthur |
| Merlin’s London Observatory | MOEL | 1920-1946 | Pr | County of London | Merlin, Augustus Alfred Cornwallis Eliot |
| Merton College Observatory | MCOO | 1300-1399 | U | Oxfordshire | Ashindon, John |
| Middlehill Observatory | MOSWD | 2007- | Pr | Dorset | Hodgkinson Robert |
| Mill Hill Observatory | See University College London Observatory [UCLO] | ||||
| Miller’s Observatory | MiO | 1850-56 | Pr | Cumberland | Miller, John Fletcher |
| Mills Observatory | MOD | 1935- | I | Angus | Mills, John |
| Minchenden School Observatory | MSOSL | 1936-1966 | S | Middlesex | Walker, William Cameron; Minchenden Grammar School |
| Mobberley’s Observatory | MobOGB | 1991-2008 | Pr | Essex | Mobberley, Martin |
| Mobberley’s Observatory | MobOC | 1980s- | Pr | Suffolk | Mobberley, Martin |
| Molyneux’s Kew Observatory | MOK | 1723-1728 | Pr | Surrey | Molyneux, Samuel |
| Monkton Combe School Observatory | MCSO | 1925- | S | Monkton Combe | Barron, Robert Percy |
| Moor Park Observatory | see Jeremiah Horrocks Observatory [JHO] | ||||
| Munday-Sayer Observatory | MSO | 1985- | I | Essex | Munday, Charles Walter; Sayer, Les; North East Essex Astronomical Society |
| Mullard Radio Astronomy Observatory | MRAO | 1945- | U | Cambridgeshire | Cambridge University |
| Murray’s Observatory | MOS | 1850- ? | Pr | Aberdeenshire | Murray, Sir William Keith |
| Nasmyth’s Observatory | NOH | 1856-1890 | Pr | Kent | Nasmyth, James |
| Naval Academy Observatory (Portsmouth) | See Royal Naval Academy Observatory [RNAO] | ||||
| Naval Academy Observatory (Gosport) | See Naval Academy Observatory [NAOG] | ||||
| Neville’s Observatory | NOGN | c.2003-? | Pr | Northamptonshire | Neville, R.J. |
| Naval Academy Observatory | NAOG | c.1800s-1822 | S | Hampshire | Burney, William |
| New City Observatory | see City Observatory [NCOE] | ||||
| Newall’s Observatory | NO | 1870-1890 | Pr | Durham | Newall, Robert Stirling; Newall, Hugh Frank |
| Newchapel Observatory | NeO | 1964-2009 | Pr | Staffordshire | Pace, Tony |
| Newnham College Observatory | NCOC | 1890- | U | Cambridgeshire | Newnham College, Cambridge |
| Nicholson’s Observatory | NOD | c.2004- | Pr | Northamptonshire | Nicholson, Martin |
| Noble’s Observatory | NOU | 1857- 1905 | Pr | Sussex | Noble, William |
| Nonsuch High School Observatory | NHSO | c.2015- | S/I | Surrey | Nonsuch High School for Girls; Ewell Astronomical Society |
| Norman Fisher Observatory | NFO | 1979- | I | Surrey | Croydon Astronomical Society; Fisher, Norman |
| Norman Lockyer Observatory | NLO | 1920- | I | Devon | Exeter University; Norman Lockyer Observatory Society (NLOS) |
| North Pennine Observatory | NPO | 2019 | Pu | Northumberland | Allenheads Contemporary Arts |
| Northrop’s Observatory | NoO | 1950s-1990s) | Pr | Surrey | Northrop, David K. |
| Nottingham Astronomical Society’s Observatory | NASO | 2006- | I | Nottinghamshire | Nottingham Astronomical Society |
| Observatory Cottage | see Hall’s Cottage Observatory [HCO] | ||||
| Observatory House | WHOS | 1786-1915 | Pr | Buckinghamshire | Herschel, William; Herschel, John; Herschel, Caroline; |
| Observatory Science Centre | OSC | 1990- | Pu | Sussex | Science Projects Limited |
| Ochtertyre Observatory | OO | 1853-1861 | Pr | Perthshire | Murray, Sir William Keith |
| Old City Observatory | OCOE | 1792-? | I | Midlothian | |
| Old Edinburgh Observatory | see Old City Observatory [OCOE] | ||||
| Old Observatory (Edinburgh) | see Old City Observatory [OCOE] | ||||
| Old Observatory, Wellington Row | see Miller’s Observatory [MiO] | ||||
| Old Royal Observatory, Greenwich | OROG | 1957-1998 | Pu | County of London | National Maritime Museum |
| O M Dark Sky Park Observatory | OMDSPO | 2021- | Pu | Tyrone | Mid Ulster District Council |
| Orwell Park Observatory | OPO | 1874- | I | Suffolk | Tomline, George; Orwell Astronomical Society (OrwAS) |
| Owen’s Observatory | OwO | 1890s-1925 | Pr | Berkshire | Owen, Arthur Edwin Brisco |
| Owens Observatory | see Manchester Physics Institute Observatory [MPIO] | ||||
| Parr’s Observatory | POSA | 1927-1936 | Pr | Hertfordshire | Parr, W. A. |
| Patrick Moore’s Observatory | PTO | 1968-2012 | Pr | Sussex | Moore, Patrick |
| Pattinson’s Observatory | PaO | 1855-1858 | Pr | Durham | Pattinson, Hugh Lee; |
| Pearson’s Observatory | POSK | 1829-1847 | Pr | Leicestershire | Pearson, William; Clark, Abrose |
| Pearson’s Temple Grove Observatory | PTGO | 1811-1821 | Pr | Surrey | Pearson, William |
| Peek’s Rousdon Observatory | PRO | 1884-1921 | Pr | Devon | Peek, Sir Cuthbert Edgar; Grover, Charles |
| Pembroke College Observatory | PeCOC | 1752 (fl.) | U | Cambridgeshire | Pembroke College, Cambridge |
| Pennell-Hammerton Observatory | PHO | 1982- | I | Lincolnshire | Lincoln Astronomical Society (LinAS) |
| Pex Hill Observatory | see Leighton Observatory | ||||
| Phillip’s Observatory | See Phillip’s Ashtead Observatory | ||||
| See Phillip’s Headley Observatory | |||||
| Phillip’s Ashtead Observatory | POH | 1907-1916 | Pr | Surrey | Phillips, T.E.R. |
| Phillip’s Headley Observatory | POA | 1916-1942 | Pr | Surrey | Phillips, T.E.R. |
| Piazzi Smyth Observatory | PSOB | 2000- | S/I | Bedfordshire | Bedford school; Smyth, Charles Piazzi |
| Piggot’s Observatory | see Pigott’s Llanwit Major Observatory [PiO] | ||||
| see Pigott’s York Observatory [PiO2] | |||||
| Pigott’s Llanwit Major Observatory | PiO | 1777-1781 | Pr | Glamorgan | Pigott, Nathaniel |
| Pigott’s York Observatory | PiO2 | 1781-1793 | Pr | Yorkshire: North Riding | Pigott, Nathaniel |
| Pond’s Observatory | JPO | 1806-1811 | Pr | Somerset | Pond, John |
| Pound’s Observatory | PO | 1717-1747 | Pr | Essex | Pound, James; Bradley, James |
| Powys County Observatory | PoCO | 1990- | I | Radnorshire | |
| Preston Municipal Observatory | 1885-1927 | see Preston Municipal Observatory [PMO] | |||
| 1927- | see Jeremiah Horrocks Observatory [JHO] | ||||
| Preston Municipal Observatory | PMO | 1882-1927 | I | Lancashire | |
| Prince’s Observatory | POC | 1857-1899 | Pr | Sussex | Prince, Charles leeson |
| Prince’s Uckfield Observatory | PUO | 1854-1872 | Pr | Sussex | Prince, Charles Leeson |
| Queen Elizabeth Grammar School Observatory | QEGSO | 2017- | S/I | Derbyshire | Queen Elizabeth Grammar School; White Peak Observing Group |