Europa: Chewy or Crunchy?  Europa: Chewy or Crunchy?  Cutout of
Europa If Europa has a "chewy" (low viscocity) core, then it
likely would have seafloor volcanoes producing conditions
conducive to life - just like the undersea volcanoes and
hydrothermal vents along Earth's mid-ocean ridges. Credit:
William B. Moore  For geophysicist William B. Moore, the
question of whether life exists on Jupiter's moon Europa boils
down to whether the moon's center is chewy or crunchy.  Many
scientists doubt life can exist on Europa's surface because of
extreme cold, lack of liquid water, the tenuous atmosphere and
intense bombardment from Jupiter's radiation belts.  Moore
believes distant Europa receives too little sunlight to provide
the energy needed for organisms to thrive on its apparently icy
surface. Others argue the chemical energy needed for life is
created when charged particles bombard Europa to produce
oxidants.  Nevertheless, says Moore, Europa's surface "would be
a very difficult place to make a living." If Euro