NASA shows off some incredible pictures of what countries look like at night from space.
This spectacular night-time view of Earth is called 'Black Marble'. It's been made up from lots of cloud-free pictures taken from one of NASA's most high tech satellites - the Suomi spacecraft.
The shots that make up this picture were taken when the Suomi spacecraft was over what's known as the dark side of Earth, the half that isn't facing the Sun. As Earth spins on its axis every 24 hours, different countries come in and out of the dark side, experiencing day and night.
On board Suomi, there's a special instrument that can take pictures even in very low light. As you can see from this shot of the UK, it's very good at picking up the light from our towns and cities.
But it's not just light that the satellite's sensitive camera picks up. The VIIRS (Visible Infrared Imaging Radiometer Suite) can make out weather patterns too - cloud, snow and fog for instance. Here's Hurricane Sandy, a powerful storm that swept across the Caribbean and north-eastern America in October.
Most of the time, all VIIRS needs to do its work is some light from the Moon. But if that isn't available, the instrument can still detect features down below just from the night-time glow of the Earth's atmosphere.
Suomi's shot of America is a tale of two halves. The built up Eastern side where loads of people live is lit up and the less developed Western side is darker. The really bright parts are some of the country's biggest cities like New York, Chicago and Los Angeles.