Are stellar birth processes and protoplanetary disk formation common and inherently similar phenomena? Included in those discoveries are the detection of rocky planets within the habitable zones of their central stars.
At which level s of organization can life forms detect the presence and direction of gravity? That could mean that DNA is a universal molecule of life, which is certainly possible. Paleontologists, evolutionary biologists and perhaps even archaeologists will be called upon to help understand the record of previous life on Earth in a planetary context - that is, what lessons can we learn from unraveling our own past to guide us as we figure out what happened on other planets?
Is there a threshold level of gravity at which sensory mechanisms respond to gravity? The Principle of Mediocrity suggests that life on Earth is not exceptional, and it is more than likely to be found on innumerable other worlds. The landers used a robotic arm to collect soil samples into sealed test containers on the craft.
A muddy definition of life will make it more difficult to interpret those results later, Voytek said. Another is that we don't know how to look for noncarbon life, since we don't know what biosignatures it might leave.