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 1991 252 observations this year — coverage 252 / 365 (69.0%)

12345678910111213141516171819202122232425262728293031Σ
Jan 1345689121316171922232627 16
Feb 34561112131416181920212628 15
Mar 245691014152223242531 13
Apr 56121317181920212225262728 14
May 123456789101213141617202123242526273031 24
Jun 12345678911121314151617181920212223242526272829 28
Jul 13478910111213141516171819202122232425262728293031 28
Aug 123456789101112131415161718192021222324252627282930 30
Sep 2356791112131415161718192021222324252627282930 26
Oct 1267891011121314151617181920212225262728 23
Nov 124567101112141516171920212223242526 21
Dec 23456141516171821262831 14

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