We love the chance to celebrate significant numbers. This punny holiday celebrates the mighty mole – One mole contains exactly 6.02214076×1023 elementary entities (approximately 602 sextillion or 602 billion times a trillion)[*], hence the celebration today! (starting at 6:02 am 10/23)
More from Mole.org:
Celebrated annually on October 23 from 6:02 a.m. to 6:02 p.m., Mole Day commemorates Avogadro’s Number (6.02 x 10²³), which is a basic measuring unit in chemistry. Mole Day was created as a way to foster interest in chemistry. Schools throughout the United States and around the world celebrate Mole Day with various activities related to chemistry and/or moles.
See more!
and more about the mole from *Wikipedia