Calendrical pareidolia

Calendrical pareidolia is the phenomenon of responding to a calendar-based stimulus by perceiving a familiar pattern where none exists (pareidolia):

Calendrical stimuli include events such as births and deaths, occurring on the same day in the calendar but otherwise evidencing no causal relationship — and yet of interest.

This article was originally titled Calendrical coincidences.

Calendar

June

June 24

1880: Mathematician and academic Oswald Veblen born. His work will find application in atomic physics and the theory of relativity. Veblen will publish a paper (1912) on the Four color conjecture.
2008: Mathematician and academic Gerhard Ringel dies. Ringel was a pioneer of graph theory and contributed significantly to the proof of the Heawood conjecture (now the Ringel-Youngs theorem), a mathematical problem closely linked with the Four color theorem.

Full June 24 page

July

July 16

1945: World War II: The heavy cruiser USS Indianapolis leaves San Francisco with parts for the atomic bomb "Little Boy" bound for Tinian Island. See Manhattan Project.
1945: Trinity nuclear weapon test: the United States successfully detonates a plutonium-based test nuclear weapon near Alamogordo, New Mexico. See Manhattan Project.
1988: Nuclear physicist Herbert L. Anderson dies. Anderson contributed to the Manhattan Project: he was a member of the team which made the first demonstration of nuclear fission in the United States, in the basement of Pupin Hall at Columbia University, and he participated in the first atomic bomb test, code-named Trinity.