In this book chapter (from the book “Mars: A volcanic World”), Nicola Mari described the potential for Martian lava tubes to provide the most practical and effective habitats for the first human missions on Mars. A lava tube is a cave made of mostly basaltic rock. Lava tubes form only during effusive volcanic eruptions. The subsequent cooling of a low-viscosity lava, which is in contact with an atmosphere once erupted from the vent of a volcano, enhances the development of a hard crust above the flow – while the lava is continuously flowing in the interior of it. In this sense, a lava tube keeps lava hot enough to continue flowing in its interior, then leaving a ‘cave’. Lava tubes can naturally protect the first humans on Mars from deadly radiations, extreme temperature variations, dust storms, and micrometeorite impacts.
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