Where the solar wind blows
Could lifeforms from Venus reach Earth by hitching a ride on the solar wind?
That's the rather startling suggestion made by two researchers following analysis of data from ESA's Venus Express spacecraft.
According to BBC Online they say that chemicals in Venus's clouds are consistent with the presence of microorganisms and that, under certain conditions, microbes from these clouds could be blown into the Earth's atmosphere.
It's an interesting idea (and a good plot for a Hollywood movie!) but according to Oxford's Fred Taylor, an Interdisciplinary Scientist for the Venus Express mission, it's pretty far-fetched.
'The idea of life on Venus, particularly the clouds where the temperature and pressure are similar to the Earth, has been floated around for a while but is not really very likely,' Fred commented, adding that it was also most unlikely that microbes could hitch a ride in this way.
Yet if you think this makes the solar wind boring you'd be wrong: two NASA missions will scour the solar wind for clues about how the planets formed and to map where the solar system ends.
Genesis is already sending back some fascinating results, including studies that show that parts of meteorites and the sun share a common pattern of oxygen isotopes - suggesting that Earth, the Moon and other bodies with a different composition are the 'odd ones out' in the solar system.
Meanwhile the planned Interstellar Boundary Explorer [IBEX] mission will chart the very edges of the sun's influence by detecting where the solar wind fizzles out and the solar system ends and interstellar space begins: at the moment the best guess is 'somewhere beyond Pluto' but after IBEX launches later this year we can look forward to a more precise answer.