October 5 is:

International Teachers day

Chic Spy™ Day 

Country Inn Bed & Breakfast Day

Portugal's Republic Day

Mid-Autumn Festival in Hong Kong

Astrophysicist Neil deGrasse Tyson's birthday

Chester Arthur's birthday

Encyclopedist Denis Diderot's birthday

Click on the date to find what special day it is:

October
7	6	5	4	3	2	1
14	13	12	11	10	9	8
21	20	19	18	17	16	15
28	27	26	25	24	23	22
				31	30	29
See also: Special days on different dates