The Large Hadron Collider is the current poster child for international collaborations in the world of high energy physics, but it's hardly the first installation to require the resources of multiple laboratories, institutions, or even countries. High energy physics—whether pursued using active particle smashers like Babar, passive detectors like Ice Cube. or out-of-this-world telescopes like XMM-Newton -- is an expensive business. Each of these projects required multi-national, multi-institutional, multi-organizational teams to plan them, build them, run them, and analyze the data.
Sometimes a project assumes a multi-national mantle for more than budgetary reasons. SESAME, or the Synchrotron-light for Experimental Science and Applications in the Middle East, with a collaboration including not only Israel but the Palestinian Authority, Pakistan and Iran, is practically performing double duty as a diplomatic mission.
But money and politics aren't the only reasons for collaborations that break national boundaries, and high-energy physics isn't the only field where these collaborations are found. Sometimes friendships, or common interests, or simply someone who knows someone who knows someone can open borders and minds.
Olivier Beauchesne of Science Metrix, a bibliometric consulting firm, plotted scientific collaborations. He used data from journal aggregators used by his workplace, and his author lists and citation networks weren't restricted to physics or biology or medicine or chemistry or any particular field.
The map takes a moment to sink in, but then it becomes clear: it's a recognizable map of the world, with continents illuminated by the lines that join them.
A map of the world.
A map of the relationships between people that make science happen.