Missing Day

I think this dates back to the first circumnavigational voyage by Magellan back in the 16th century. When the ships finally made it back to port they discovered they were missing a day according to their log books (and the Spanish kept meticulous log books). This is because there was no International Date Line. I first heard of this in geography class back in the 1970s but can’t find any references online.

I have no trouble believing that Magellan’s logs were faithful enough to show a one day difference compared to the ones at his home port, but was the point of the story that anyone was surprised? Was it told as if Magellan returned, thinking it was August 15, but the locals informed him that it was really August 16, and there was a mystery until somebody thought of the “ship lag” they would have experienced?

I would find this surprising; after all, the people who did this navigation stuff were pretty smart, Christopher Columbus excepted.

Welcome to the SDMB, haynes.

A link to the column you’re commenting on is appreciated. Providing one can be as simple as pasting the URL into your post, making sure to leave a blank space on either side of it. Like so: http://www.straightdope.com/classics/a3_083.html

[nitpick]Magellan didn’t make it home - but (I think one?) of the ships did[/nitpick]

As did the Portuguese, for whom Magellan was sailing.

I would think you would have had to make Earth stand still…(relative to our sun that is) to make this happen… so the missing day would manifest itself in a discrepency in the position of the Earth? Which makes no sense, since why would scientists worry about the Earth in thier sims, I wouldn’t think the body the satelites orbit poses much of a threat?

Wasn’t Professor Harold Hill the name of the con man in “The Music Man”?

So, Cecil’s column was fine, but if a day were missing from the calendar, for the sake of argument, it would not be detectable by a mathematical model of planetary motion anyway.

Suppose we consider the sweep of the hour hand of a clock as the rotation of the earth. It’s trivial to write a math function that will predict where the hour hand will be at any future time.

This allows a determination of where it was in the past as well, by virtue of the math.

Suppose the hand effectively stands still for an hour, or skips ahead a full hour like it did last week for the US folks. How would this be determined, given its current position and a function describing all future positions?

Unless someone was watching at the time that it occurred, it’s undetectable.

Yes. Though this is just coincidental, since, as Cecil alludes to in passing in the column, there actually was a (plain) Harold Hill involved in spreading the story. He had nothing to do with NASA and was merely particularly important in resurrecting an older version of the myth and then both vigorously and credulously passing it on. Hence how his name got attached to it in later mutations.
Snopes has more detail about him.

And the fact that this eludes so many people makes me despair for our species. Unfortunately, what Clarke never told us is that to most folks, our current level of technology is indistinguishable from magic.

As a teen Charismatic in the late 70s, I devoured Harold Hill’s books. In retrospect, I’ve always wondered how truthful his other tales were after seeing the Missing Day one debunked.

getting back to Haynes’ OP - are you sure it was Magellan, and not:

Phineas Fogg in Jules Verne’s Around the World in Eighty Days?

It just seems to me that if I go westward the sun sets a little later by my clock. If I count days as being sunset to sunset, by the time I have circled the earth I have counted one less sunset than I would have had I stayed in one place.

Oops. Sorry ignorablent I thought your were referring to the circumnavigation but I see you were speaking of the missing Biblical day. My mistake.

I’m not sure about that. Lewis Carroll was stumped by the theoretical issue (in A Tangled Tale), and the “lost-day” paradox is also a plot point in Le tour du monde en 80 jours.

I’m too lazy to look it up, but…

Isn’t it “Phileas” Fogg?

Yes, “l” and not “n”. I’d always thought it was “n” but just looked it up on Wikipedia.