Five O'Clock Somewhere

Welcome to Five O'Clock Somewhere, where it doesn't matter what time zone you're in; it's five o'clock somewhere. We'll look at rural life, especially as it happens in Rio Arriba County, New Mexico, cats, sailing (particularly Etchells racing yachts), and bits of grammar and Victorian poetry.

Monday, January 19, 2009

Antipodean musings

If you dig a hole straight down, where DO you come out?

I was looking at my visitor stats, and I noticed I had a visitor from a very long way away, in this case, Pakistan, more than 7,000 miles away. That got me to thinking, where is the point that is the farthest possible distance from Five O’Clock Somewhere?

That would be the antipode, the point on the Earth exactly opposite. I remember being told as a child that if I dug a hole straight down, I would come out in China – but that’s not true. If you are in North America, a hole straight down will not come out in China, because China is in the northern hemisphere, and a hole dug in the northern hemisphere is going to come out in the southern.

Antipodes are important for cruising sailors. They define when a sailor has truly circumnavigated the Earth – in order to count, the sailor has to pass through at least one pair of points that are directly opposite each other. Otherwise, the sailor could simply sail a short loop around Antarctica (admittedly not easy, but still a much shorter distance).

Calculating the latitude of the antipode is easy – if one is in the northern hemisphere, the latitude is the same, but south instead of north. Since Five O’Clock Somewhere is at about 37 degrees north latitude (actually a few minutes less, but we’re not going for precision at the moment), its antipode will be about 37 degrees south.

The longitude is a little trickier to calculate. Five O’Clock Somewhere is west of the Prime Meridian, and the antipode will be the same amount west of the International Date Line. So I can take 107 degrees west (again, a rough approximation), subtract it from 180 degrees east, and I end up with 73 degrees east.

So what is at 37 degrees south, 73 degrees east? Well, not much. It’s in the Indian Ocean, east of Madagascar and a little bit south. It’s kinda-sorta close to the island of Diego Garcia.

So my best bet for a true antipodean visitor is somebody stationed at Diego Garcia. Of course, these guys are dedicated to their jobs of protecting the United States’ interests in a very volatile part of the world – they support air operations in the Middle East. But when they have time off, I invite them to join the party at Five O’Clock Somewhere.

Labels: , , ,


Anonymous tillerman said...

Fascinating stuff. You may be right that your best bet for a (near) antipodean visitor is one of the guys at Diego Garcia. But Diego Garcia is at 7 degrees S, about 2000 miles from your true antipodes.

A much nearer piece of land is Ile Amsterdam at 37S 77E, one of the only three islands that are the antipodes for spots in the continental United States.

As far as I can gather there aren't many readers of sailing blogs on Ile Amsterdam, only the staff of a French meteorological station. But you can hope!

Mon Jan 19, 09:03:00 AM MST  
Blogger Carol Anne said...

Of course, if somebody is out sailing in the Indian Ocean and keeping track of the world via satellite, that person could check in from the right spot.

Tue Jan 20, 04:14:00 PM MST  
Blogger Gerald said...

Yup, I found an Antipoedean (or should i say antipodal?) map tool. La Roche Godon (Ile Amsterdam) is the closest antipodal land to Five O'Clock Somewhere. It's antipodal to some point near La Junta in southeastern Colorado. Go figure that Colorado has two of the US's antipodes. Ile Saint-Paul is just to the south of Ile Amsterdam.

The map tool is here:

Mon Feb 09, 06:12:00 PM MST  

Post a Comment

<< Home