A German-American research team of biologists and geochemists has discovered hitherto unknown anaerobic bacteria in marine sediments which need only propane or butane for growth.

The hydrocarbons ethane, propane and butane – as well as the main component, methane – are the major constituents of natural gas. Biological processes may lead to the degradation of these hydrocarbons in underground petroleum reservoirs and other geological habitats.

Heinz Wilkes, a leading biogeochemist at GeoForschungsZentrum Potsdam (GFZ), points out: „The bacteria isolated here for the first time from marine sediments use sulphate instead of oxygen for respiration and utilize propane and butane as their sole source of carbon and energy.

Every now and then a space rock hits the world's media – sometimes almost literally. Threatening asteroids that zoom past the Earth, fireballs in the sky seen by hundreds of people and mysterious craters which may have been caused by impacting meteorites; all make ESA's planned mission Don Quijote look increasingly timely.

The uncertainty surrounding whether a meteorite impacted in South America recently highlights the need to know more about these pieces of natural space debris and their trajectories. ESA has always been interested in such endeavours and conducted a number of studies into how it might best help.

Researchers have discovered that even the gruesome and brutal lifestyle of the Evarcha culicivora, a blood gorging jumping spider indigenous to East Africa, can’t help but be tempted by that ‘big is beautiful’ mantra no matter what the costs.

A study recently published in Ethology found that despite the inherent risk of sexual cannibalism, virgin females were attracted to bigger males when losing their virginity before opting for the safer smaller male as a longer term mate choice.

Everyone knows how a bicycle works - or so we think. But for 150 years why a moving bicycle can, all by itself, be so stable has been something of a mystery.

"Bicycle manufacturers have never been able to say precisely how a bicycle works," explains Dr Arend Schwab of the Faculty of Mechanical, Maritime and Materials Engineering (3mE). "They have always had to refine their designs purely through experimentation. In our model, they can enter into the computer all of the various factors that influence the stability and handling of their bicycle.

The majority of patients who undergo male to female sex-change surgery are happy with the results, despite the fact that complications are common, according to a study of over 200 patients in the September issue of the urology journal BJU International.

A research team from the Departments of Urology and Psychiatry at University Hospitals of Leicester NHS Trust, UK, explored the initial experiences of 222 patients who had undergone surgery and 70 who took part in detailed follow-ups.

They found that 88 per cent of patients were happy with their surgery at their first post-operative clinic visit, seven per cent were unhappy and five per cent made no comment.

"We've never seen anything quite like it," says solar physicist Lika Guhathakurta from NASA headquarters.

Last week she sat in an audience of nearly two hundred colleagues at the "Living with a Star" workshop in Boulder, Colorado, and watched in amazement as Saku Tsuneta of Japan played a movie of sunspot 10926 breaking through the turbulent surface of the sun. Before their very eyes an object as big as a planet materialized, and no one was prepared for the form it took.

"It looks like a prehistoric trilobite," said Marc De Rosa, a scientist from Lockheed Martin's Solar and Astrophysics Laboratory in Palo Alto, Calif.