How far away is space, really?

Where does space really begin?

For education and comparison, NASA JPL uses the edge of space at about 100 km / 62 miles above sea level. That means “space” is much closer than many people imagine. The International Space Station, by contrast, flies at about 400 km altitude, which is four times farther up than that first edge-of-space benchmark.

This makes for a surprisingly good everyday thought experiment. A 100 km drive is long, but normal. The strange part is not the distance itself — it is that the distance is straight up.