On 40

Forty (40) offers a lot of significance, so there is no way to capture forty’s vast nature. Of course, I imagine John will include his share of military references (which I, and hopefully everyone, will appreciate).

Nonetheless, I dedicate this post to the members of my graduating class who recently came together to celebrate our 40 years since high school graduation.

In Mathematics

  • 40 is an octagonal number and a Stormer number
  • Adding up some of its divisors (1, 4, 5, 10 and 20) equals 40, 40 is a semiperfect number
  • To add hours and minutes easily, use 40. Example, to add 2 hr 40 min and 3 hr 30 min, use 240 + 330 + 40 = 610, therefore, 6 hr 10 min

In Science

  • The atomic number of zirconium, which has 40 protons, thus 40 electrons in its neutrally charge state
  • The planet Venus forms a pentagram in the night sky every eight years with it returning to its original point every 40 years with a 40 day
  • Messier object M40 is a magnitude 9.0 double star in the constellation Ursa Major
  • Counting from the woman’s last menstrual period.the number of weeks for an average term of pregnancy

In Religion
The number 40 is significant in the Abrahamic traditions  (some examples)


  • Rain fell for “40 days and 40 nights” during the flood
  • Spies explored the land of Israel for “40 days”
  • The Hebrew people lived in the Sinai desert for “40 years”
  • Several Jewish leaders and kings (Eli, Saul, David, Solomon) ruled for 40 years
  • Goliath challenged the Israelites twice a day for 40 days before David defeated him
  • Moses spent three consecutive periods of “40 days and 40 nights” on Mount Sinai
  • 40 lashes is one of the punishments issued by the Sanhedrin


  • Before the temptation of Christ, Jesus fasted “40 days and 40 nights”
  • Lent consists of the 40 days preceding Easter. However, Western Christianity excludes Sundays while Eastern Christianity includes Sundays
  • The period from the resurrection of Jesus to the ascension of Jesus is 40 days


  • Muhammad was 40 years old when he first received the revelation delivered by the archangel Gabriel
  • Prophet Ibrahim spent 40 days in a fire and lived because Allah made the fire like flowers
  • Prophet Yunus was in a whales mouth for 40 days
  • Muhammad was praying and fasting in the cave for 40 days
  • Muhammad had 40 followers to spread the religion of Islam
  • Mourning period officially last for 40 days

In Cultures

  • Some Russians believe that ghosts of the dead linger at the site of their death for 40 days
  • In Hinduism, some popular religious prayers consist of 40 shlokas or dohas (couplets, stanzas)
  • To understand a people, you must live among them for 40 days. (Arabic proverb), then again, others say “Life begins at 40″
  • The ruby wedding anniversary
  • The customary number of hours in a regular workweek in some Western countries

In Sports

  • Major League Baseball allows each team to have a 40-player roster with major-league contracts at any given time (not including players on the 60-day disabled list)
  • The 40 yard dash is an important metric in football (US) scouting.
  • The third point gained in a tennis game

Retired #40

  • In Major League Baseball: Don Wilson (Astros) and Danny Murtaugh (Pirates)
  • In the NBA: Bill Laimbeer (Pistons), Jason Collier (Hawks), and Byron Beck (Nuggets)
  • In the NFL: Gale Sayers (Bears), Mike Haynes. (Patriots), Tom Brookshier (Eagles), Joe Morrison (Giants), and Pat Tillman (Cardinals)

Old Rosebud won the 40th Kentucky Derby (1914)

NASCAR #40 has won 5 races, led by Sterling Marlin (4). Other drivers include Kenny Wallace, Robby Gordon, David Stremme, Jamie McMurray, Bobby Hamilton, and Dario Franchitti

Steelers defeated the Seahawks in Super Bowl XL

In US History

  • 40 acres and a mule refers to the short-lived policy, during the last stages of the American Civil War
  • The 40th United States Congress (1867-1869) during the third and fourth years of Andrew Johnson’s Presidency, which impeached President Johnson and completed the Alaska Purchase
  • President Ronald Reagan, the 40th US president
  • James K Polk’s slogan: Fifty-four Forty or Fight

In Geography

  • Interstate 40 links California to North Carolina
  • U.S. Route 40 links Baltimore, Maryland, to Park City, Utah, which generally parallels I-70
  • European route E40 links Calais and Ridder, A40  links London and Fishguard), and M40 links London and Birmingham.
  • The 40th parallel north crosses Europe, the Mediterranean Sea, Asia, the Pacific Ocean, North America, and the Atlantic Ocean.
  • The 40th parallel north serves as the boundary between Kansas and Nebraska
  • The 40th parallel south cross much more water than land (Argentina, Chile, Australia (Tasmania), and New Zealand)

In Entertainment

  • A song by Dave Matthews Band
  • A 1983 song by U2 from their album War
  • The radio program American Top 40
  • In The Early Show segment “Chef on a Shoestring”, chefs are given a $40 budget
  • $40 Rachel Ray’s budget for food per day when visiting a city in the show $40 a Day

In the Year 40 AD

  • A leap year starting on Friday
  • Roman Emporer Caligula starts on a campaign to conquer Britain, fails miserably, declares himself victorious, and then he appoints his horse, Incitatus, a senator
  • The Vietnamese Trung sisters rebel against the rule of the Chinese Emperor Guangwu of Han
  • Philosopher Philo teaches that all men are born free
  • Christianity comes to Egypt as a church in Alexandria
  • Mark the Evangelist founds the Coptic Orthodox Church as the first pope
  • An early Christian church erects in Corinth

In the Year 40 BC

  • Either a common year starting on Thursday, Friday or Saturday or a leap year starting on Thursday or Friday
  • Treaty of Brundisium: The Roman Republic divided into spheres of influence. Gaius Octavian takes control of the Western provinces while Mark Antony gets the Eastern provinces; The marriage of Antony and Octavia, sister of Octavian seals the treaty

Miscellaneous about Forty

  • The code for direct dial international phone calls to Romania
  • The caliber of the bullet in a number of firearms cartridges, most notably the .40 S&W
  • A great lubricant, WD-40, named after the 40 attempts it took to find this water displacement formula
  • Ali Baba and the 40 Thieves, who didn’t have this 40-ounce malt liquor available to them
  • 40 winks references sleep

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