Nasa's Curiosity rover finally drills deep enough into Martian rock to acquire a powdered sample for analysis - a historic first in planetary exploration.

The funeral of a teenage girl who was shot dead a week after performing at President Obama's inauguration has been held in Chicago.

New York has been spared the worst of the storm, but some neighbourhoods that are still recovering after Hurricane Sandy, are now facing another clean-up.

A major snowstorm brings areas of the north-eastern US and Atlantic Canada to a standstill, with hundreds of thousands of homes without electricity.

A major snowstorm in the north-eastern US and eastern Canada leaves to hundreds of thousands of homes without electricity and paralyses transport.

Snow is falling around the US north-east, which is braced for a "potentially historic" storm that could see up to 3ft (91cm) of snow in some areas.

John Kerry prompts a Gallic shrug by refusing to answer a question in French at his first news conference as US secretary of state.

Members of an Afghan youth orchestra arrive in the US to tour iconic music venues and use music to shape their country's future, says the BBC's Jane O'Brien.

An Ohio Amish sect leader is sentenced to 15 years in prison, with shorter terms for his followers, for a spate of beard-cutting attacks in 2011.

The parents of Hadiya Pendleton, a teenage girl shot dead days after appearing in President Obama's inauguration celebrations, have told the BBC that US gun laws have to change.

A Canadian navy intelligence officer is sentenced to 20 years in prison after pleading guilty to selling classified Nato information to Russia.

US internet firm AOL reports its first year-on-year revenue growth for eight years, boosted by strong advertising sales, sending its share price higher.

Shares in the US credit rating agency Moody's fall 7.7% in trading in New York on Friday amid fears of legal action surrounding rating agencies.

Monopoly, Beyonce and snow, all in 140 characters or fewer

Boeing warns customers awaiting delivery of new 787 Dreamliners to expect delays amid a continuing investigation into their safety.

The search for a fired Los Angeles policeman who vowed to bring "warfare" to his former colleagues and their families moves to a snowy mountain range.

The cost of Obama's secret drone war

Is this the most beautiful railway station in the world?

A New Orleans power firm says the Super Bowl blackout was caused by faulty device designed to prevent failure of cables leading to the Superdome.

A narrowing in the US trade deficit during December raises hopes that the economy was stronger in the final quarter of 2012 than first estimated.