Astronaut Samantha Cristoforetti's best photos of Earth from space

These clouds were spotted by Cristoforetti on day 195 of her 199 days in space (the longest spaceflightever achieved by a woman). They're "noctilucent"clouds -- the highest clouds in the Earth's atmosphere, thin wisps on the edgesof upper atmosphere polar mesospheric clouds. They glow brilliantly at deep dusk.

The Caribbean from space is a stunning array of colours, as sudden peaks and troughsaround the islands give hue to the blue waters -- from deepest royal blue topale turquoise. You can see why pirates would need accurate charts of thedepths.

The deepest hypersaline lake in the world, with a surface429 metres (1,407 feet) below sea level, is the Dead Sea,located on the border between Palestine, Israel and Jordan. It's so salty thatnothing can live in it and the density of salt is so high that anyone caneasily float on its surface. It's also, sadly, receding:potable water that would normally flow into the sea has been used by humancolonies nearby, making much of the shoreline unsafe.

The neuronlikeglow of connected cities from space: Athens, Greece, glowing brightly in the lower middle,with the lower section of the boot of Italy in the upper left. Lightning flashes in the upper right over the very western corner of Romania.

Cirrus and altocumulus clouds over the coast of Venezuela, with the sun turning the water into a brightly gleaming mirror.

The ISS travels at a pretty high speed: 7.66 kilometres persecond (27,600 km/h, 17,160 mph), at an obliqueangle around the Earth. This means that astronauts on the station see the sun rise and set 15 or 16 times every 24 hours. If you love sunrise and sunset beyondall reason, you might want to think about becoming an astronaut.

Many astronauts report, upon seeing the beauty of Earth laid out, an overwhelming feeling of love and kinship with otherhumans. This is known as the overview effect.

This is Jubbah, asmall town in the desert of Saudi Arabia, north and east from capital cityRiyadh. Originally built some 7,000 to 9,000 years ago, Jubbah is home to somecurious ruins and relics. It's one of the most importantlocations for rock-art carvings in the Middle East. Its carvings includepetroglyphs and ancient inscriptions in Thamudic, a pre-Islamic North Arabicdialect.

This image is upside down. North was facing downward whenCristoforetti took it.

The variety of clouds, clockwise from upper left: a Karman vortex street, usually causedby the separation of wind flow around a mountain top, creating a series ofvortices in the clouds; stratocumulus castellanus; cirrocumulus castellanus;and clouds pulling together into the spiral rain bands of a hurricane.

The oceans cover 71 percent of the Earth's surface, so manyphotos of the Earth from space show water. This photo shows the opposite: the desert of Darfur, in the NorthAfrican republic of Sudan.

Patterns of the Earth, clockwise from top left: Qasr al-Farafra in western Egypt; westof the Exuma Trough in the Bahamas; the Tibesti mountain range in the northwestof Chad, North Africa; the desert in the south of Saudi Arabia, near the Yemenborder.

This is Cristalinain the state of Goias, Brazil, south of the capital, Brasilia. The circles arecreated by centre-pivot irrigation, where sprinkler equipment rotates arounda centre pivot, creating a circular area that gets watered.

In the foreground, the Canadian-built robotic maintenancearm, Dextre,against a dramatic backdrop of glowing green aurora arcing over the horizon.

North of the Falkland Islands, fishing boats glow in the Argentine Basin on the west edge of the South AtlanticSea. Clouds provide a veil through which the coloured lights diffuse.

The deep eye of Typhoon Maysak, an unusually intense cyclone for the 2015 Pacific typhoonseason. It affected both the Philippines and Micronesia, developing aroundMarch 26-28 and intensifying into a supertyphoon on March 31, when thisphotograph was taken.

Cristoforetti's home country,glowing golden at night through a soft layer of cloud.

Emi Koussi,on the southeast of the Tibesti Mountains in Chad, North Africa, is a volcano,but no longer active. It's an uncommon pyroclastic shield volcano -- that is, atype of volcano formed by magma.

Not the kind that wants to kill Sarah Connor. The terminator -- also known as "the twilight zone" -- is the movingline that separates the light side of a planet from the dark. Who knew thatdusk was so badass.