This article is from the source 'bbc' and was first published or seen on . It last changed over 40 days ago and won't be checked again for changes.

You can find the current article at its original source at http://www.bbc.co.uk/news/science-environment-25349395

The article has changed 5 times. There is an RSS feed of changes available.

Version 0 Version 1
Jupiter's icy moon Europa 'spouts water' Jupiter's icy moon Europa 'spouts water'
(35 minutes later)
Water may be spouting from Jupiter's icy moon Europa - considered one of the best places to find alien life in the Solar System.Water may be spouting from Jupiter's icy moon Europa - considered one of the best places to find alien life in the Solar System.
Images by the Hubble Space Telescope show surpluses of hydrogen and oxygen in the moon's southern hemisphere, say astronomers writing in Science journal.Images by the Hubble Space Telescope show surpluses of hydrogen and oxygen in the moon's southern hemisphere, say astronomers writing in Science journal.
If confirmed as water plumes, it raises hopes that Europa's underground ocean can be accessed from its surface.If confirmed as water plumes, it raises hopes that Europa's underground ocean can be accessed from its surface.
Future missions could probe these seas for signs of life.Future missions could probe these seas for signs of life.
Astrobiologists have said that, in theory, organisms could survive in the oceans of Europa, but feared the moon's thick icy crust may be an impenetrable barrier to life.
Tidal forcesTidal forces
US physicists looked at images taken by Hubble in November and December of last year, as well as older images from 1999. In this new study, US physicists looked at images taken by Hubble in November and December of last year, as well as older images from 1999.
In two distinct southern regions, they saw evidence of water being broken apart into hydrogen and oxygen - revealed by ultraviolet light signatures.In two distinct southern regions, they saw evidence of water being broken apart into hydrogen and oxygen - revealed by ultraviolet light signatures.
"They are consistent with two 200km-high (125-mile-high) plumes of water vapour," said lead author Lorenz Roth, of Southwest Research Institute, San Antonio, Texas."They are consistent with two 200km-high (125-mile-high) plumes of water vapour," said lead author Lorenz Roth, of Southwest Research Institute, San Antonio, Texas.
These "plumes" appear to be transient - they arise for just seven hours at a time. These giant geysers appear to be transient - they arise for just seven hours at a time.
They peak when Europa is at its farthest from Jupiter (the apocentre of its orbit) and vanish when it comes closest (the pericentre).They peak when Europa is at its farthest from Jupiter (the apocentre of its orbit) and vanish when it comes closest (the pericentre).
This means that tidal acceleration could be driving water spouting - by opening cracks in the surface ice, the researchers propose.This means that tidal acceleration could be driving water spouting - by opening cracks in the surface ice, the researchers propose.
They say the plumes may be like those seen on Saturn's moon Enceladus - with high-pressure vapour emissions escaping from very narrow cracks. They say the vapour jets may be like those seen on Saturn's moon Enceladus - with high-pressure emissions escaping from very narrow cracks.
The results were reported at the American Geophysical Union (AGU) Fall Meeting in San Francisco, California.The results were reported at the American Geophysical Union (AGU) Fall Meeting in San Francisco, California.