Details of the bluetongue virus, including where it comes from and how it is transmitted.

Scientists think a giant asteroid impact can explain why the northern and southern hemispheres of Mars look so different.

The disaster threatened by China's fast-rising quake lakes potentially dwarves that triggered by the tremor which spawned them this month, warn experts.

Work starts to provide detailed surveys of the site of the proposed new Forth road bridge.

As the Kenyan parliament prepares to meet for the first time since disputed elections last month, young people are pressing the older generation to make way.

Plans by India to realign part of its electrified border with Pakistan receive a warm welcome from farmers, reports the BBC's Asit Jolly.

Volunteers help archaeologists search for signs of a medieval castle in a village car park in Pembrokeshire.

A detailed map of the medieval temple of Angkor Wat in Cambodia reveals the extent of the sprawling urban settlement

Two animations allow viewers to "hang-glide" over terrain currently being explored by Nasa's Mars rovers.

Scientists using data from a European space probe orbiting Mars have produced new topographic maps of the Red Planet.

MSPs hear that the boundaries of the UK's biggest national park should be extended into Perthshire.

Clearance operations for the £155m Waverley line from Edinburgh to the Borders will start within weeks.

The homes of Nigerians are being lost to advancing sands from the Sahara at an alarming rate each year, the BBC's Senan Murray discovers.

A collection of rare maps of Africa, dating back to 1530 are made available for free online by a US university.

Roadworks to improve an accident blackspot on the Isle of Man are on schedule to finish ahead of time.

Europe's Venus Express spacecraft is sending back a treasure trove of data on Earth's sister planet.

Scientists rediscover the millipede with the most legs 80 years after its first and only sighting. The world's leggiest millipede has been rediscovered 80 years ago after its first and only sighting.

Rescue teams call off their latest search for a missing hill walker but admit they are now looking for a body.

Work begins on making a mountainside less steep after a landslide threatened to engulf a street.

Campaigners want to rename a mountain near Bangor after a medieval Welsh princess.