Earth

Last week, the Earth had its closest shave with an asteroid ever recorded, when a small space rock skimmed just 370 km (230 miles) above the surface. For comparison, that’s closer than the orbit of the International Space Station.

Asteroid Apophis has attracted its share of attention, with several projected close shaves with Earth in the coming decades. While most have been ruled out, a previously-overlooked factor has opened a small window for a possible collision in 2068.

A new study has identified 1,004 stars from which aliens could detect signs of life in Earth’s atmosphere by watching as our planet passes across the disk of the Sun. The study could help provide targets for groups searching for alien civilizations.

The face of the Earth has changed drastically over its life, with plates shifting and sinking. Now geologists claim to have found the remains of an ancient tectonic plate beneath Canada, which was pushed under the surface millions of years ago.

NASA has announced the selection of five Medium Class Explorer concept mission proposals that could one day revolutionize our understanding of the space environment, and see pictures taken of the Sun's polar regions.

A new experiment placing bacteria on the outside of the International Space Station (ISS) has found that micro-organisms can survive in space for years, or even decades. The study lends weight to the idea that life could travel between planets.

Astronomers have identified an asteroid that made the closest pass to Earth ever recorded, and it was only spotted after it had passed. The object skimmed Earth’s atmosphere over the weekend, close enough to have its orbit changed by the gravity.

Earth is a famously watery planet, but where exactly it all came from is a mystery. Now researchers have suggested a new origin story, by showing that water and petroleum can form inside clouds of organic matter, at high temperatures and pressure.

Researchers have now found evidence that some of the world’s most impressive gems, such as the Hope Diamond and the Cullinan – which adorns the Crown Jewels – originated much deeper in the Earth’s mantle than previously thought.

Current levels of carbon dioxide in the atmosphere are the highest they’ve been in a long time. According to a new study of fossil plant matter, CO2 concentrations haven’t been this high in at least 23 million years, and have never shot up this fast.

When did Earth's plate tectonics begin? A new study from Yale University claims to have found evidence that plate tectonics started about a billion years earlier than is currently thought, which places it very soon after the planet’s formation.

A new paper has revealed that Greenland and the Antarctic have lost a staggering amount of mass from their ice sheets over the last 16 years thanks to climate change, and that the melting has contributed to sea level rise.