Globe model and antipode calculator


Here is a model globe that puts Mathematica's WorldPlot perimeter list into Martin Kraus' LiveGraphics3D applet. It's interesting that Georgia appears to be the only state in the contiguous US that is given its own outline! Also, note how the fast drawing algorithm gives rise (in effect) to a bit of ad hoc edge transparency. This model was assembled as part of our program for developing empirical observation exercises for teachers with the energy to work some pedagogically-sound content-modernization into classes with a bit of web-access. We might, for example, put an adaptation of this to use in our powers of ten explorer in days ahead.

It is also easy to add functionality here (e.g. javascript buttons for reporting latitude and/or measuring the distance between points) if there is interest. We've already added a few labels (including a red gravitube), and a couple of javascript buttons. The latter include one that allows you to figure out where you'd "come up" if you dug a hole through the center of the earth from where you're at now. It's amazing how many of us would come up in the middle of an ocean somewhere. In fact, the hard part may be to find someone who wouldn't! Does that conversely mean that fish that dig too far are likely to come up on land?



Gravitube puzzlers: What cities does the gravitube connect? How deep does it run at its deepest point? Is the ocean that deep? How much time would it take for an unpowered trip between end points, if frictionless travel could be arranged?

Antipode puzzlers: What continental regions lie opposite to the South Pacific Ocean, the Indian Ocean, the North Atlantic Ocean, and the Central Pacific Ocean? What ocean is antipodal to the South Atlantic Ocean? These oceans may be the two best places for fish with a passion for deep excavation! As far as land-lubbers are concerned, if you dug a hole through the center of the earth from China, where would you really come up? Does the table below help to accurately visualize these relationships (not counting the poles) by making antipodes the same color? How would you change it, or can you think of an even better way? Ten or eleven of the 24 squares in the table below (those in italics) might be considered "continental". How many continental antipode-pairs do you find? How many oceanic (non-italic) antipode-pairs do you find? Is there some geological reason why 9 of the 12 antipode-pairs in the table below are mixed, i.e. why dry regions of the earth's surface tend to be opposite to wet ones?

North America North Atlantic Western Europe Eastern Europe Middle East and Asia Far East North Pacific North East Pacific
Central America Caribbean Central Atlantic North Africa North Indian Ocean South East Asia Western Pacific Central Pacific
South East Pacific South America South Atlantic South Africa South Indian Ocean Australia South West Pacific South Pacific