Astronauts never fail to point out the beauty of seeing planet Earth from space, and it must be a surreal experience watching entire continents drift by as they orbit in the International Space Station.
But these images vary considerably in terms of how much of the entire globe of planet Earth is seen in one shot.
Depending on during which mission the image of Earth was captured, you might be able to make out the intricate detail of lakes and rivers, towns and cities, or simply the whole blue disc of our planet set against the inky backdrop of deepest, darkest space.
So how far away does an astronaut need to be in order to observe the whole of planet Earth in one go?
To see the whole of our planet in one view, an astronaut would have to be further away than you may imagine.
As an example, from 300km (200 miles) above 52ºN 0ºW, only Europe is seen, and at 1,000km (600 miles) much of northern Africa becomes visible, but with less surface detail.
By 36,000km (22,000 miles) above the ground, the full disc of planet Earth could be seen by a human being.
This latter altitude is the position of a geostationary satellite, a satellite that appears to be in a fixed position because it revolves around the equator once per day, and it needs three of these satellites to give a full view of the planet.
To put this into perspective, the International Space Station orbits Earth from a distance of about 250 miles (400km), which is why images of Earth captured from the Space Station reveal so much detail.
You can experiment with this yourself by using the website Fourmilab, where you can get a view of Earth from any point of altitude, latitude or longitude.
And Google Earth of course helpfully tells you how far its 'camera' is from ground level, meaning you can zoom in and out to see what the perspective is from different distances.
Zoom into 400km and you'll get an idea of how ISS astronauts see Earth; you'll realise it's much closer than you might have imagined.