LEGO Globe (Lowell sphere method)
2012.08.25 R.I.P. Neil Armstrong - You're one of the privileged few who got to see the Earth from this vantage point. Thanks for inspiring me.
2012.06.27 Images updated, with associated text
2012.06.12 LDraw / POV-Ray renders added
2012.05.07 Project Published
This is a model I hope to build soon, and I think it would make a great project for LEGO CUUSOO: a mid-scale LEGO Globe and stand. It's educational, affordable, and showcases an impressive but straightforward technique for making smooth-looking spheres (and other 3D sculptures) out of simple LEGO plates.
This method for building spheres was first demonstrated by Bruce Lowell. The outer surface of the hollow sphere is composed of six identically shaped panels. Basically, the six panels are shaped and arranged like those on a standard volleyball. The beauty of the method is that each panel can straightforwardly be built out of simple LEGO plates.
Here's a view of what one of these panels may look like with a sphere diameter of 24 studs:
(adapted from Bram Lambrecht's Sphere Generator at http://lego.bldesign.org/sphere/) The six panels are built individually, and then are attached at right angles (as if to the faces of a central cubic core) with the studs facing outward in each of the six directions. It's an elegant technique which yields a beautifully smooth and sturdy result, and is definitely not something one would expect from typical block-shaped LEGO.
The main image at the top of the page is a POV-Ray render of the mockup I've started in LDraw/MLCad. Below is a closeup in LDView, which better shows the individual plates.
For utmost accuracy, I created the model by overlaying the blank mockup with views from Google Earth. The Prime Meridian, Antimeridian, 90th Meridian East and West, and Equator run along the center lines of each panel. At the current scale, each surface stud at the Equator covers a little over 5 degrees of longitude.
For posterity, I've included here the original main image from the project, showing a Google Earth overlay, as several comments refer to this image. For the actual model, land masses will be mainly monochromatic (green) as above, with tan for major deserts of the world, and with Antarctica and appropriate Arctic regions, e.g. Greenland, in white.
At this scale, the globe will require on the order of approximately 1500 pieces (mainly small plates and optionally 1x2 jumper plates). To minimize the piece count, the jumper plates could be replaced with regular plates, at a slight reduction in resolution and smoothness. Also, due to the scaling of surface area with the square of the radius, a small reduction in the size of the sphere can reduce the number of plates substantially. Such details are best left to the production phase. :)
I estimate that this model could be produced at a cost of around $100 or so. (Unlike many popular CUUSOO models, this project does not involve any licensed intellectual properties, contributing to keeping the cost down.)
This last image shows a mockup with a simple stand. I would suggest making the stand out of clear plates/bricks, for visual impact and to further highlight the globe by creating a floating effect. Also shown is the recent Naboo globe with a stand, to give a better feel for the intended final result.
To summarize, this model showcases a universally recognized subject, highlights an advanced-but-straightforward building technique, is reasonably priced, and has universal appeal as a display piece, educational tool, and sculpture.
If you've read this far, please consider voting to see it produced! Thanks!
PS: If you like spheres made out of LEGO, check out my latest CUUSOO project at https://ideas.lego.com/projects/16974, a Star Wars Death Star II wall/desk clock sculpture!