# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

**Re: Equation of Time (Travel)**

**From:**Frank Reed

**Date:**2007 Dec 15, 21:45 -0500

Lu Abel, you wrote: "Hey, this is fun!" Glad you liked it. I laughed out loud when I saw the Equation of Time in the movie. Seriously, has it ever been in a film before? I'm sure I've seen "analemmas" on globes in films before, and that implicitly includes the EqT, but never the actual equation. And you wrote: > 1. The "Equation of Time Travel" is really the Equation of Time. E is > the time (in minutes) ahead or behind zone noon that the sun will pass > directly over a time zone's principal meridian. The particular representation of the Equation of Time here exactly matches the write-up on the Wikipedia page so I suspect they just copied from there. And: > 2. The first equation requires a "B" value. If B is measured in > degrees, then the equation is B = 360 (N - 81) / 365, where N is the day > of the year (N = 1 for Jan 1st ... 365). Some references use 364 > instead of 365 as the denominator. So the first part of the movie's > equation for B is sort of correct (see comment below in item 3) but then > there's the second term with fanciful stuff like the square root of Pi * > i (where i in turn is the square root of minus 1). Yes, the second part, which you call "fanciful", is obviously the part that makes time travel possible. ;-) For question 3, what I was suggesting is that the equation as given is only an approximation. So how far would you go wrong using it as written? Two seconds? Ten seconds? Thirty? For extra credit, the scene is set in the year 3007. What would be the correct Equation of Time for that era? And you wrote: > 4. It's Bender, the robot (full name Bender Bending Rodriguez or > Bending Unit 22) from the TV series Futurama. > http://en.wikipedia.org/wiki/Bender_%28Futurama%29 Good ole Bender. > > My kid introduced me to Futurama. Now you know what to ask for for Christmas. :-) I actually saw this movie five days before it went on sale. That seems appropriate for a time travel story. -FER --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To unsubscribe, send email to NavList-unsubscribe@fer3.com -~----------~----~----~----~------~----~------~--~---