Science

Faster-than-light particles, or "tachyons", may be fundamentally impossible, according to two mathematical physicists. If they're right, their new theory would also imply that time – seemingly one of the most fundamental facets of nature – is no more than a mirage.

Although it is commonly believed that Einstein's theory of relativity says nothing can go faster than light, that is not quite true. Relativity does forbid ordinary matter from ever reaching the speed of light, because it would require infinite energy.

After a nearly two-day pursuit, the U.S. space shuttle Discovery arrived at the International Space Station (ISS) and docked with it at 5:19 p.m. EDT (2119 GMT)on Tuesday as they flew over southern Australia, according to NASATV.

The linkup took place some six minutes behind the planned docking time of 2113 GMT.

Forget the memory-boosting pills: In the future, powers of recall could be boosted with programs on a handheld PDA.

Researchers have found a telltale mental signature that predicts whether an experience will be remembered. Once deciphered, the signals could be used to help people know when their brains are primed to remember, perhaps using an iPhone app.

The launch of space shuttle Discovery, scheduled for Wednesday night, has been cancelled due to an apparent leak in the shuttle's external fuel tank, according to NASA. "A slight leak was detected in a gaseous hydrogen vent line," NASA wrote on its Web site.

NASA says it may try another launch on Thursday at 8:54 p.m. EDT, "depending on what repairs are needed and what managers decide." NASA said managers would meet late Wednesday to discuss the issue.

WE don't yet know why HIV spreads to women so much more readily in Africa than elsewhere, but African women desperately need protection from the virus during sex. Now a cheap and relatively safe chemical that damps down vaginal inflammation may do just that.

NASA launched its Kepler spacecraft just before 11 p.m. Friday in a mission that the agency says may fundamentally change humanity's view of itself.

The Kepler spacecraft blasted into space on top of a Delta II rocket from Cape Canaveral Air Force Station in Florida. The telescope will search our corner of the Milky Way galaxy for Earth-like planets.

Aeroplanes will be too afraid to crash, yoghurts will wish you good morning before being eaten and human consciousness will be stored on supercomputers, promising immortality for all - though it will help to be rich.

These fantastic claims are not made by a science fiction writer or a crystal ball-gazing lunatic. They are the deadly earnest predictions of Ian Pearson, head of the futurology unit at BT.

China's lunar probe crashed into the moon Sunday in a controlled collision at the end of a 16-month mission, state media reported.

Xinhua News Agency cited sources at the State Administration of Science, Technology and Industry for National Defense as saying the Chang'e 1 lunar satellite hit the moon at 4:13 p.m. local time (0813 GMT) on Sunday.

The satellite was under remote control by two observation and control stations in east China's Qingdao and Kashgar, a small city in northwest China, Xinhua said.

More than a third of the most common cancers in developed countries could be prevented by healthy eating and exercise, says a report by the World Cancer Research Fund (WCRF). In developing countries like China and Brazil, it estimates that a quarter of common cancers are preventable.

These figures do not include smoking, which alone accounts for about a third of cancers.

It's an advertisement you might see someday, if testimony given to the British House of Lords this month is to be believed. In remarks that have stirred up a tempest in the British press and on the Internet, Baroness Susan Greenfield, a neuroscientist at the University of Oxford, warned that the instant feedback and impersonal communication offered by social networking sites could drive human brains and behavior in negative directions.