From family and friends to strangers on the subway and public figures on 24-hour news cycles, humans recognise an astonishing 5,000 faces, scientists said Wednesday in the first study of its kind.

Through most of history humans lived in small groups of a hundred or so individuals, a pattern that has changed drastically in recent centuries.

The Hubble space telescope, which has been in orbit since 1990, is currently out of action because of a gyroscope failure, the U.S. space agency said Monday.

Almost a week after a quake-tsunami wreaked devastation in central Indonesia, scientists are zeroing in on what they believe caused the highly unusual natural disaster.

Two American astronauts and a Russian cosmonaut returned to Earth Thursday wrapping up a six-month mission at the International Space Station as tensions between Washington and Moscow threaten a rare area of cooperation. 

U.S. scientists Frances Arnold and George Smith and British researcher Gregory Winter won the Nobel Chemistry Prize on Wednesday for applying the principles of evolution to develop enzymes used to make everything from biofuels to medicine.

Arnold, just the fifth woman to clinch chemistry's most prestigious honour since Marie Curie was honoured in 1911, won one half of the nine million Swedish kronor (about $1.01 million or 870,000 euros) award, while Smith and Winter shared the other half.

Mosquito larvae have been observed ingesting microplastics that can be passed up the food chain, researchers said Wednesday, potentially uncovering a new way that the polluting particles could damage the environment.

Microplastics -- tiny plastic shards broken down from man-made products such as synthetic clothing, car tyres and contact lenses -- litter much of the world's oceans.

NASA counted down Saturday to the launch of its $1 billion ICESat-2 mission, using advanced lasers to uncover the true depth of the melting of Earth's ice sheets.

SpaceX on Thursday announced a new plan to launch a tourist around the Moon using its Big Falcon Rocket (BFR), a massive launch vehicle that is being designed to carry people into deep space.

NASA's Mars rover Curiosity has snapped a dusty but cool selfie.

NASA released the panorama this week. A thin layer of dust is visible on Curiosity , the result of a storm that enveloped Mars this summer. The darkish sky indicates dust still clogging the atmosphere in August, when the panorama was shot by Curiosity's mast camera. The rover had just drilled for a new rock sample.

Russia launched checks Tuesday after its space chief said an air leak on the International Space Station last week could have been deliberate sabotage.