Name Date Association Location County
| Macdonald, Thomas Logie | 1901-1973 | Lanarkshire | ||
| Mackay, Andrew | fl.1780s-1790s | Aberdeen | Aberdeenshire | |
| Maclear, Thomas | 1794-1879 | Maclear’s Observatory [MOB] | Newtownstewart | Tyrone |
| Madge, Ernest Alcwyn [Alewyn] | 1876-1961 | Swansea | Glamorgan | |
| Main, Robert | 1808-1878 | Upnor | Kent | |
| Malden, Anne Douglas | 1881-1961 | Cambridge | Cambridgeshire | |
| Maloney, Francis Joseph Terence | 1917-2008 | Mortlake | Surrey | |
| Manning, William Henry | 1883-1952 | Cambridge | Cambridgeshire | |
| Markwick, Ernest Elliott | 1853-1925 | Markwick’s Observatory [MaOD]; Markwick Observatory [MaOWM]; Markwick’s Observatory [MaOB] | Boscombe | Hampshire |
| Marsden, Brian Geoffrey | 1937-2010 | Cambridge | Cambridgeshire | |
| Marsh, Narcissus | 1638-1713 | Armagh | Armagh | |
| Marth, Albert | 1828-1897 | Bishop’s Observatory [BORP] | London | County of London |
| Martyn, Richard | fl. 1808-1828 | Goldsithney | Cornwall | |
| Maskelyne, Nevil | 1732-1811 | Royal Observatory, Greenwich [ROGL] | Greenwich | County of London |
| Mason, Charles | 1728-1786 | Lifford | Donegal | |
| Mattey, Sidney Batt | 1886-1940 | Plumstead | County of London | |
| Maunder [nee Russell], Annie Scott Dill | 1868-1947 | Greenwich | County of London | |
| Maunder, Edward Walter | 1851-1928 | Greenwich | County of London | |
| Maw, William Henry | 1838-1924 | Maw’s Observatory [MOO] | Outwood | Surrey |
| Maxwell, Somerset Henry | 1849- | Wexford | ||
| May, Charles | 1800-1860 | May’s Observatory [MaO] | Ipswich | Suffolk |
| McCance, James Law | 1856-1903 | McCance, John | London; Newry | County of London ; Armagh |
| McCance, John | 1859-1893 | McCance, James Law | Worthing; Newry | Sussex ; Armagh |
| McClean, Frank | 1837-1904 | McClean’s Ferncliffe Observatory [MCOF]; McClean’s Rushall Observatory [MCOR] | Tunbridge Wells | Kent |
| McCrea, William Hunter | 1904-1999 | Chesterfield | Derbyshire | |
| McEwen, William
Henry Duncan |
1864-1955 | Glasgow | Lanarkshire | |
| McGregor, Alexander | 1834-fl.1871 | Grantown | Inverness | |
| McNally, Derek | 1934-2020 | Mill Hill Observatory [MHOL] | Mill Hill | County of London |
| Mee, Arthur Butler Phillips | 1860-1926 | Llanelli | Carmarthenshire | |
| Mees, Chales Edward Kenneth | 1882-1960 | Catherham | Surrey | |
| Meers, Arthur William | fl.1898-1907 | Streatham; Beckenham | Kent | |
| Mellor, Thomas Milner | 1847-1924 | Huddersfield | Yorkshire: West Riding | |
| Merlin, Augustus Alfred Cornwallis Eliot | 1860-1946 | Merlin’s London Observatory | London | County of London |
| Merryweather, John | NK | Lincoln Castle Observatory Tower [LCOT] | Lincoln | Lincolnshire |
| Merton, Gerald | 1893-1983 | Mill Hill | County of London | |
| Michell, John | 1725-1793 | Eakring | Nottinghamshire | |
| Mitchell, A.E. | fl.1902-1907 | Dublin | Dublin | |
| Middlehurst, Barbara | 1915-1995 | Penarth | Glamorgan | |
| Milburn, William | 1896-1982 | Tow Law | Durham | |
| Miller, John Fletcher | 1816-1856 | Old Observatory, Wellington Row [MiO] | Whitehaven | Cumberland |
| Mills, Caradoc | 1883-1950 | Llanrwst | Denbighshire | |
| Mills, Edward | 1802-1865 | Llanidloes | Montgomeryshire | |
| Milne, Edward Arthur | 1896-1950 | Hull | Yorkshire: East Riding | |
| Molyneux, Samuel | 1689-1728 | Molyneux’s Kew Observatory [MOK] | Kew | Surrey |
| Monck, William Henry Stanley | 1839-1915 | Dublin | Dublin | |
| Moore, Patrick Alfred Caldwell | 1923-2012 | Patrick Moore’s Observatory [PTO] | Selsey | Sussex |
| Morgan, Augustus De | 1806–1871 | London | County of London | |
| Morgan, John Holdsworth | 1825-1908 | Cambridge | Cambridgeshire | |
| Morgan-Jones, J. C. M. | 1895-? | Pwllheli | Caernarvonshire | |
| Morris, P. | NK | Cambridge | Cambridgeshire | |
| Moss, Walter | 1878-1958 | Cambridge | Cambridgeshire | |
| Murdoch, James | 1809-fl.1851 | Garmouth | Morayshire | |
| Nasmyth, James | 1808-1890 | Nasmyth’s Observatory [NOH] | Edinburgh | Midlothian |
| Naylor, Frederick William | 1810-1859 | Nottingham | Nottinghamshire | |
| Newall, Hugh Frank | 1857-1944 | Newall’s Observatory [NO] | Cambridge | Cambridgeshire |
| Newall, Robert Stirling | 1812-1889 | Newall’s Observatory [NO] | Dundee | Angus |
| Newing, Robert Albert | 1913-1984 | Bangor | Caernarvonshire | |
| Newton, Isaac | 1642-1727 | Colsterworth | Lincolnshire | |
| Newton, John | 1621-1678 | Lavendon | Buckinghamshire | |
| Noble, William | 1828-1904 | Noble’s Observatory [NOU] | Uckfield | Sussex |
| Northrop, David | NK | Northrop’s Observatory [NoO] | Nottingham | Nottinghamshire |
| Norton, Arthur Philip | 1876-1955 | Cardiff | Glamorgan | |
| Offord, J.M. | fl.1885-1920s | London | County of London | |
| Orr, Mary Acworth | 1867–1949 | See Evershed | ||
| Ostriker, Jeremiah | 1937- | Cambridge | Cambridgeshire | |
| Oughtred, William | 1575-1660 | Eton | Buckinghamshire | |
| Owen, Arthur Edwin Brisco | 1858-1925 | Ufton Nervet | Berkshire | |
| Owen, Derek | -1989 | Pensarn | Denbighshire | |
| Owen, Edwin Vaughan | 1870-1950 | Dolgellau | Merionethshire | |
| Owen, Gwilym | 1880-1940 | Denbigh | Denbighshire | |
| Owen, John R. | -1975 | Llanrhystud | Cardiganshire | |
| Owen, Owen John | 1867-1960 | Dolgellau | Merionethshire | |
| Palmer, John | 1612-1679 | Northampton | Northamptonshire | |
| Panther, Roy W. | 1926-2016 | Northamptonshire | ||
| Parker, D. | NK | Cambridge | Cambridgeshire | |
| Parker, George, second earl of Macclesfield | c.1697–1764 | Shirburn Castle Observatory [UOO] | Wallingford | Oxfordshire |
| Parr, William Alfred | 1865-1936 | St. Albans | Hertfordshire | |
| Parry, Maldwyn Tecwyn | d. c. 1988 | Bangor | Caernarvonshire | |
| Parsons, Lawrence 4th earl of Rosse | 1840–1908 | Birr Castle Observatory [BCO] | Dublin | Offaly |
| Parsons, William, 3rd earl of Rosse | 1800-1867 | Birr Castle Observatory [BCO] | Dublin | Offaly |
| Pattinson, Hugh L. | 1796-1858 | Pattinson’s Observatory [PaO] | Gateshead | Durham |
| Payne-Gaposchkin, Cecilia Helena | 1900-1979 | Wendover | Buckinghamshire | |
| Peacock, George | 1791-1858 | Gainford | Durham | |
| Pearson, William | 1767-1847 | Pearson’s Observatory [POSK]; Pearson’s Temple Grove Observatory [PTGO] | Whitbeck | Leicestershire |
| Peat, Thomas | 1708-1780 | Nottingham | Nottinghamshire | |
| Peck, William | 1862-1925 | Castle Douglas | Kirkcudbrightshire | |
| Peek, Bertrand Meigh | 1891-1965 | Canterbury | Kent | |
| Peek, Sir Cuthbert Edgar | 1855-1901 | Peek’s Rousdon Observatory [PRO] | Rousdon | Devon |
| Penrose, Louisa Petitot | c.1851-1938 | See Freeman | ||
| Perrins, Charles William Dyson | 1864-1958 | Malvern | Worcestershire | |
| Perrins, James Dyson | 1823-1887 | Davenham Bank Observatory [DBO] | Worcester | Worcestershire |
| Perry, Geoffrey | 1927-2000 | Kettering | Northamptonshire | |
| Perry, Stephen Joseph | 1833-1889 | Stonyhurst College | Lancashire | |
| Pether, Abraham | 1756-1812 | Chichester | Sussex | |
| Phillips, John | 1800-1874 | Oxford | Oxfordshire | |
| Phillips, Theodore Evelyn Reece | 1868-1942 | Phillip’s Headley Observatory [POH] | Headley | Surrey |
| Phillips, William | 1870-? | Llandudno | Caernarvonshire | |
| Pierce, E T. | NK | Cambridge | Cambridgeshire | |
| Pigott, Edward | 1753-1825 | Llantwit Major | Glamorgan | |
| Pigott, Nathaniel | 1725-1804 | York | North Riding | |
| Pither, Colin | NK | Charminster | Dorset | |
| Plaskett, Harry Hemley | 1893-1980 | Oxford | Oxfordshire | |
| Player, John | 1842-1931 | Thirlestaine Hall Observatory [THO] | Cheltenham | Gloucestershire |
| Plummer, Henry Crozier Keating | 1875-1946 | Oxford | Oxfordshire | |
| Plummer, John Isaac | 1845-1925 | Cambridge | Cambridgeshire | |
| Plummer, William Edward | 1849-1928 | London | County of London | |
| Pogson, Norman Robert | 1829-1891 | Bishop’s Observatory [BORP] | Nottingham | Nottinghamshire |
| Pond, John | 1767-1836 | Royal Observatory, Greenwich [ROGL]; Pond’s Observatory [JPO] | Greenwich | County of London |
| Pope, John D. | 1924-2001 | Hersmonceux | Sussex | |
| Pope, Walter | 1628-1714 | London | County of London | |
| Porthouse, William | 1878-1964 | Manchester | Lancashire | |
| Potchett | NK | Newark | Nottinghamshire | |
| Pound, James | 1669-1724 | Pound’s Observatory [PO]; Bradley’s Observatory [BrO] | Wanstead | Essex |
| Prentice, John Philip Manning | 1903-1981 | Stowmarket | Suffolk | |
| Priestley, Joseph | 1733-1804 | Northampton | Northamptonshire | |
| Prince, Charles Leeson | 1821-1899 | Prince’s Uckfield Observatory [PUO]; Prince’s Observatory [POC] | Crowborough | Sussex |
| Pritchard, Charles | 1808-1893 | Oxford | Oxfordshire | |
| Proctor, Richard Anthony | 1837-1888 | Chelsea | County of London | |
| Prydderch, John | c.1582-c.1624 | Nantyrhebog | Carmarthenshire |