Ananova:

Star Trek-style space travel could soon be possible as researchers devise engines which generate massive thrust from tiny amounts of anti-matter.

Experts are warning it won't come on the cheap - with the anti-matter fuel required currently costing about $6,400 trillion (£4,300 trillion) per gramme to produce.

But as little as one millionth of a gramme could power a one-year manned mission to Jupiter, according to a report in the Journal of Propulsion and Power.

Physicist Gerald Smith, one of the founders of Synergistic Technologies, a consulting firm which specialises in anti-matter applications for NASA and the US Air Force, said: "The requirements for anti-matter propulsion are much lower than anyone thpought before."

His study concluded "the prospects of exploiting anti-matter for space propulsion are not so bleak after all and may indeed be quite favourable".

Anti-matter propulsion would enable space exploration to take a massive step forward, with rocket scientists able to send advanced probes far beyond Pluto, the Boston Globe newspaper reports.

One of the study's co-authors, George Schmidt, deputy director of the Propulsion Research Centre at NASA's Marshall Flight Centre, said: "If you look at the conventional technologies, they're just not good enough. That's why we are so excited about this."

The anti-matter engine designs have been analysed using computer models, but not yet tested manually as there is not enough anti-matter in existence.