The word “astronaut” means “star sailor” in its origins.

 

The word “astronaut” means “star sailor” in its origins.  

 

It is derived from the Greek words “astron”, meaning “star”, and “nautes”, which means “sailor”.

So, the word astronaut literally means “star sailor”. 

We heard a lot in August 2021 about the “edge of space” and the life-changing effects of going to it. But wait a minute—does space even have an edge?

Space is everywhere. It permeates everything, as water does a sponge. In fact, the volume each of us occupies in the world is mostly empty space. What Jeff Bezos, Richard Branson, and their clients went to the edge of was not space, but the Earth’s atmosphere. And of course, the atmosphere does not have a real edge either; it just gradually gets harder and harder to detect.

People realized, way back at the beginning of our spacefaring era, that de-fining the edge of “outer” space—that is, all space that is not within a certain matter-rich sphere, precise diameter to be determined—would be important for jurisdictional reasons. The famed aerodynamicist Theodore von Kármán suggested a value in the vicinity of 60 miles, because at that altitude a winged vehicle could squeeze only negligible lift from the vanishingly thin air. The precise height of the so-called Kármán Line, 100 km or 62 miles, is arbitrary, just a nice round number. In order to make a few of its X-15 pilots into space travelers, the U.S. Air Force created an ersatz “edge” of its own, at 50 miles.

Von Kármán was evidently thinking about air more than space. If he had been thinking about real airlessness, he might have suggested a different boundary, for instance 150 km, or roughly 100 miles. That, in Wikipedia’s nicely phrased definition, is “the lowest altitude above the Earth at which an object in a circular orbit can complete at least one full revolution with-out propulsion.”