Recently there is Sea found below the surface of ice on one of the planet `s moon,?

You mean Enceladus? It's entirely possible life exists under the ice, that's why NASA and several space agencies are studying the moon more closely, even sending probes specifically to study the moon. But if there's life on Enceladus, it probably has no resemblance to Earth. People always base life that may be on other places on life found here. Watch Through the Wormhole, specifically the episode about alien life, which shows life that may have evolved and adapted to the harsh conditions of places such as Io, Titan or on planets in other parts of the galaxy.

There are a number of moons and dwarf planets that are thought to have subsurface oceans. Ganymede, Europa, Enceledas, and Ceres are among them.

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<Is there any possibility of life?> There's a possibility of life anywhere liquids are found, especially liquid H2O. It's not impossible that the gas giants harbor some sort of dense atmospheric life, though that is firmly in the realm of science fiction. It's not impossible that places like Titan, with its methane/ethane/propane lakes and seas could contain lifeforms, obviously very different than we know of here on Earth. There is a vast gap between 'possible' and 'probable', though.

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<when [will science] will discover it?> While many unhinged people claim to be clairvoyant, nobody can actually prove they are under scientifically controlled conditions. Why do you imagine it's possible to predict future events such as these?

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The possibility exists... It's anybody's guess right now of how *likely* life is - ranging from definitely to not at all... until we can place a probe on the the ice, and melt through to take a peek... it's Schroedinger's Cat - there *might* be life....

It's possible,don't think it's likely though