Life in a Lava Tube on Mars

Life in a Lava Tube
Lava River Cave, Arizona

Lava tubes on Earth are dark and cold places. It’s unclear what they may be like on Mars, but perhaps someone will find out. Future Martian explorers may experience life in a lava tube.

Camping out on Mars is not a good idea. There is no breathable atmosphere, and the radiation is deadly. Without much of an atmosphere, the temperature on Mars varies extremely. On a summer day near the equator, the temperature may reach a comfortable 70 degrees F (20 degrees C). However, without the thermal blanket of an atmosphere, the night-time temperature can drop to minus 100 degrees F (minus 73 C). At the poles, the temperature can get down to minus 195 F (minus 125 C). The average temperature on Mars is minus 80 degrees F (minus 60 C).

Transporting materials to build a suitable shelter on Mars would be difficult. Any structure would have to be small and still might not give adequate protection from radiation. The surface of Mars receives unfiltered solar radiation, cosmic rays, and ionized particles from the solar wind. With the lack of an atmosphere or a magnetosphere, which we have on Earth, there is nothing to block the dangerous radiation. The amount of radiation is many times what astronauts experience in the International Space Station (ISS). NASA limits astronaut exposures in the ISS to months. Explorers might have to spend years on Mars. Just getting there will take about seven months.

What does this have to do with life in a lava tube, and what are lava tubes anyway? During a volcanic eruption, molten lava can bore its way through the ground and run out into the open. When the molten lava exits, it often leaves behind a cave-like underground tube. I explored the Lava River Cave (bottom picture) in Arizona, located in the Coconino National Forest. The walls are black basalt, which the lava left behind, and there is no light except at the entrance. The temperature remains constant at around 40 degrees F (4 degrees C). In most places, the ceiling is high enough that I could stand up, but in other areas, I had to crouch down or get on my hands and knees. The top picture shows a larger lava tube in Iceland.

Researchers have detected what appears to be lava tubes on Mars near Hadriacus Mons, which is a volcanic mountain formed long ago when the Martian interior was hot. They suggest that those lava tubes would be the best location for a Martian outpost. The lava tubes would give protection from the radiation, and it might even be possible to seal one off, pressurize it with oxygen, and heat it. They tested the radiation protection concept in some lava tubes on Earth, including the Lava River Cave in Arizona.

All of this drives home how blessed we are to have a home on planet Earth. I can step outside on a beautiful day, breathe the oxygen, feel the filtered rays of sun on my face, enjoy the pleasant temperature, and thank God for the blessings. Stepping out of the lava tube on Mars without the protection of a super-spacesuit would mean instant death. Even though I enjoyed exploring the lava tube in Arizona, I wouldn’t want to live there. Life in a lava tube does not interest me. I enjoy living on this planet, which God designed to give us everything we need if we will just take care of it.

— Roland Earnst © 2020