To view the Earth from a distance of 4,000 km
A test:
How to see the full Earth at once (with the blackness of space around it).
Let's imagine we wanted to have a 60 degrees wide Earth in front of us. The earth having a 12,000 km diameter, the thing to do is to locate the eyes in the middle of Earth, from a distance of 10/12th the size of the Earth's diameter.
In reality: 10,000 km from the center of our planet, meaning 4,000 km from its surface.
Will astronauts ever orbit the Earth far enough to have that view?
Raoul