The Mars cover package says that if the probes landing this week find frozen surface water, it could indicate that liquid water remains in the planet's warmer interior and that life could exist there.
Finding frozen surface water is an indication of life on Mars.
mnli hypothesis: Finding frozen surface water is an indication of life on Mars. premise: The Mars cover package says that if the probes landing this week find frozen surface water, it could indicate that liquid water remains in the planet's warmer interior and that life could exist there.