What immediate physical effect does Mars's near-vacuum pressure have on body fluids?
Answer
Water rapidly boils away or sublimates directly into vapor, even at freezing temperatures.
The surface pressure on Mars is less than one percent of Earth's sea-level pressure, which causes water to immediately transition out of its liquid state, an essential first step in the preservation process.

Related Questions
Why does decomposition not occur on the Martian surface as it does on Earth?What immediate physical effect does Mars's near-vacuum pressure have on body fluids?What terrestrial process closely resembles the desiccation occurring to organic material on Mars?What is the approximate average temperature hovering on the Martian surface?What mechanism acts as a barrier against the survival of terrestrial bacteria accidentally introduced to the Martian surface?If left on Mars, what primarily determines the long-term structural failure of a body, ignoring biological action?What is the defining characteristic of Earth's decomposition process that is absent on Mars?What is the functional difference between burial on Earth versus burial on Mars regarding organic material?What feature of the Martian environment prevents fluid retention in organic tissues?What potential information might a long-preserved Martian artifact retain that a skeleton decades old on Earth might lack?What are the three components comprising the Martian environment's tripartite defense system against decay?