The jury is still out over ALH84001, but there exists the intriguing possibility that life, if it arose in those early days on Mars, could still be eeking out an existence beneath the surface where sub-surface water is believed to exist. However, another potential site for life in our solar system is Jupiter's moon, Europa . It has a rocky core surrounded by a thick coating of water ice. There is substantial evidence from the Galileo space probe that a global ocean of liquid water exists beneath the surface crust of water ice, melted by gravitational flexing from Jupiter. There is the possibility therefore, that life may exist within this subsurface ocean.
Black smokers are volcanic chimneys protruding from the Earth's oceanic crust.
They gush hot water tremendously high temperatures. NASA are developing the Europa Orbiter is to investigate this moon further. Gas giant planets similar to Jupiter have recently been discovered in close orbits around other stars. Such discoveries are exciting, and there is yet more to come. Planet hunting is a burgeoning area of activity in astronomy.