HITCHHIKER’S GUIDE TO THE GALAXY Alien bugs hitching a ride to earth will NEVER be allowed to escape due to contamination fears

Mars or Jupiter’s moon Europa samples will be contained forever as they pose a risk to humans.

DANGEROUS alien bugs hitching a ride back to Earth on returning space crafts should be locked away forever, a leading scientist has said.

Rock and ice samples brought back from Mars or Jupiter’s moon Europa would be isolated forever if necessary, said Dr John Rummel, senior scientist at the Seti Institute in Mountain View, California.

Europa is a frozen moon of Jupiter which looks totally inhospitable and barren, but might be hiding alien life.

Nasa is planning to dispatch robotic craft to explore freezing mini world’s concealed oceans.

Many experts are worried about the risk of Earth microbes contaminating other worlds during space exploration.

But there are also concerns about extraterrestrial bacteria or viruses accidentally picked up from the surface of other planets invading the Earth.

Such pathogens are likely to be hardy survivors, and human immune systems may be powerless against them.

Dr Rummel is taking part in a talk on space contamination at the American Association for the Advancement of Science (AAAS) annual meeting in Boston.

He said: “If we bring samples back from either Europa or Mars, we will contain them until hazard testing demonstrates that there is no danger and no life, or continue the containment indefinitely while we study the material.

“It is assumed that such life would be hardy – to survive the trip to Earth; not easy – and precautions taken would provide a very high degree of containment.”Microbes may conceivably be living to this day on Mars below the planet’s radiation-baked surface.

And scientists believe Europa has a global salty ocean beneath its icy crust which may well harbour simple life.