The International Space Station (ISS) welcomes scientific guests, that is, experimental modules that have reserved berths in the ISS’s payload racks. In a sense, the ISS is a scientific cruise ship. It is extraordinarily exclusive even though the accommodations are plain, the provisions are sparse, and the attentions of the busy astronaut staff are, necessarily, fleeting.
The ISS can skimp on luxuries because it is the ultimate cruise to nowhere, circling the globe endlessly in near-zero gravity. Aboard the ISS, conditions prevail that laboratories on the Earth’s surface cannot match, conditions that give scientific guests the opportunity to generate unexpected and novel results.