Interstellar travel

Nasa is reportedly planning an interstellar mission in 2069 to search for life outside our solar system in the three-star Alpha Centauri system. The mission is as yet unnamed and the technology required to get a craft there does not exist, but the projected launch date would coincide with the 100th anniversary of the first moon landing.

The ambitious mission would require a craft that would need to travel at a minimum of 10 per cent of the speed of light. The Alpha Centauri constellation is 4.4 light years away, and even if a record-breaking tenth of the speed of light could be achieved, the system would still be a 44-year trip, reaching our nearest neighbour by 2113.

“It’s very nebulous,” Anthony Freeman, at Nasa’s Jet Propulsion Laboratory, told the New Scientist. Nasa is said to be considering sending tiny probes powered by lasers, which in theory may be able to reach a quarter of the speed of light. Other techniques under consideration include harnessing nuclear reactions, or through collisions between antimatter and matter, the magazine reported.

There is already a known exoplanet in the Alpha Centauri star system, Proxima Centauri b, which orbits a red dwarf star. However, it has not been considered a perfect location for finding alien life, as the star throws out bursts of radiation that make the conditions inhospitable.

So far humans have only made one spacecraft that has successfully left our solar system — the Voyager 1 craft —, which was launched in 1977 and despite the limitations of the technology it was equipped with, provided astonishing new insights into the planets and moons within our own solar system.

Grave risk

A team of international researchers, led by the University of Sheffield, UK, have measured the risk of developing or dying from the life-threatening heart condition called infective endocarditis, for people with predisposed heart conditions.

The new study, led by professor Martin Thornhill from the University of Sheffield’s School of Clinical Dentistry, shows that men were more than twice as likely to develop IE as women and that the risk peaked in young children and the elderly. “Those with artificial or repaired heart valves and certain congenital heart conditions were at much higher risk of developing or dying from IE than the general population,” said Thornhill.

“And the risk of developing IE again was even higher in those who previously had IE. Surprisingly, the risk of IE was substantially reduced in those with repaired congenital heart defects although those in whom the repair involved shunts or conduits had a much higher and progressively worsening risk of developing or dying from IE.”

In recent years there have been an increasing number of people in whom implantable pacemakers and defibrillators have been inserted to treat heart problems and the study showed for the first time that these individuals also have an increased risk of IE. It is a serious heart infection that kills around a third of those who develop it within the first year and causes long-term and serious disability in those who survive.

The findings, published in the European Heart Journal, are particularly important because they allow prevention measures to be targeted at those individuals most at risk of developing IE and they allow clinicians and patients to better evaluate the risk of this complication before procedures such as artificial heart valves, implanted pacemakers are performed.

These findings may also help international guideline committees to improve their guidance on the prevention of IE and the risks associated with different cardiac procedures.