Skynet becomes self-aware today

In the first episode of Terminator: The Sarah Connor Chronicles, the terminator Cameron, played by Summer Glau, says:

The Skynet missile defense system goes online April 19, 2011, declares war on mankind, and triggers a nuclear apocalypse two days later.

The exact time is frequently given on the Internet as 20:11, or 8:11 p.m., although I don't know what time zone this is supposed to be, nor can I find the exact quote this time was taken from.  I also find it curious that the time is the same as the year, suggesting that someone may have mistaken one for the other.

If it's Eastern Time, it just now happened.  I believe that Skynet was located in Colorado, which could mean that we have two more hours.  If it's Universal Time, then it would correspond to MJD 55670.841, which was several hours ago.

In Terminator 2, and presumably in the original movie, there was a different date (50689.260):

The Skynet Funding Bill is passed. The system goes on-line August 4th, 1997. Human decisions are removed from strategic defense. Skynet begins to learn at a geometric rate. It becomes self-aware at 2:14 a.m. Eastern time, August 29th. In a panic, they try to pull the plug.

Judgment Day is averted at the end of this movie, but in Terminator 3, which was released in 2003, we find that it was merely delayed until July 25, 2004 6:18 pm Eastern Time (53211.929).

The events in the 2008 TV series take place after T2 and creates an alternate timeline, having the characters travel forward in time so that John Connor, who was supposedly born in 1985, can still be a teenager in the present day.  This is how Skynet's awakening is delayed until today.  Judgment Day will now happen on Thursday. (55672)

Good luck to you all!

MJD 55671.029
[via SF Weekly]

Go ask Alice

Yesterday I saw the movie Alice in Wonderland and I noticed the price tag on the Mad Hatter's hat said "10/6".  I recognized that it was a price in old English currency of ten shillings and six pence.  Since there were twenty shillings in a pound and twelve pence in a shilling, 10s 6d would today be equivalent to 52½p or £0.525, although halfpennies stop being minted in 1984.

That got me thinking of duodecimal measures.  The words "inch" and "ounce" both come from the Latin uncia, meaning a twelfth part, and there are twelve inches in a foot, and twelve troy ounces in a troy pound, although other types of ounces no longer represent a twelfth of anything.

Years are divided into twelve months.  Originally sun dials divided the period of daylight into twelve hours, which varied in length depending on location and time of year, but eventually mechanical clocks came to represent periods between midday (noon) and midnight, and these clocks are divided into twelve hours of equal length.  An additional hand likewise divides each hour into twelve parts; adding marks between the numerals multiplies this division by five, giving 60 minutes, but have you ever noticed that the time is almost always rounded to the nearest multiple of five minutes, so we're still dividing hours by twelve?

A dozenal system of units would be fine, and in some ways better than decimal, but traditionally there have been only a handful of dozenal units.  A shilling were divided into twelve pence, but a penny was divided into two ha'pennies or four farthings, a pound into twenty shillings, etc.  Since Decimal Day, 1971 February 15 (MJD 40997), a pound is divided into 100p, period.

MJD 55269.198