Istanbul University Faculty of Science

SOLAR OBSERVATIONS

Istanbul University Observatory · Sunspot observations since 1950

Observatory

Photosphere Drawing Archive

20,582 observation days · 1950–2026

Years Select a year to see its observation days

19509 days 1951266 days 1952291 days 1953303 days 1954292 days 1955299 days 1956299 days 1957299 days 1958307 days 1959280 days 1960271 days 1961261 days 1962254 days 1963258 days 1964274 days 1965279 days 1966261 days 1967297 days 1968278 days 1969266 days 1970291 days 1971283 days 1972251 days 1973303 days 1974292 days 1975302 days 1976287 days 1977275 days 1978271 days 1979285 days 1980256 days 1981288 days 1982301 days 1983295 days 1984290 days 1985292 days 1986278 days 1987254 days 1988272 days 1989209 days 1990293 days 1991252 days 1992273 days 1993265 days 1994283 days 1995275 days 1996235 days 1997237 days 1998248 days 1999265 days 2000272 days 2001276 days 2002279 days 2003252 days 2004280 days 2005236 days 2006238 days 2007285 days 2008141 days 2009107 days 2010194 days 2011289 days 2012315 days 2013312 days 2014312 days 2015297 days 2016316 days 2017300 days 2018294 days 2019303 days 2020247 days 2021245 days 2022279 days 2023266 days 2024269 days 2025245 days 2026188 days

Photosphere Drawing Archive 1964 274 observations this year — coverage 274 / 366 (74.9%)

12345678910111213141516171819202122232425262728293031Σ
Jan 1236111314171920242526272829 16
Feb 689111213182526 9
Mar 3121416212223262728293031 13
Apr 1235789101112131415161718192021222324252930 25
May 1234567891112141518192122232425262728293031 26
Jun 1234567891011121415161718192021222324252627282930 29
Jul 1234567891013141516171819202122232425262728293031 29
Aug 12345678910111213141516171819202122232425262728293031 31
Sep 123456789101112131415161718192021222527282930 27
Oct 12345678910111213141516171819202122232425262728293031 31
Nov 12345789101213141617182021232526272830 23
Dec 12351415161718192425293031 15

Orange cells mark days with a drawing; click to open it (use the ← → keys to browse).