[Rockhounds] How lava caves on Earth helped scientists find one on the Moon

[Kreigh Tomaszewski]

Sometimes, a hole in the ground is just a hole. Other times, it’s a portal
to an underground cave spanning miles in width and length. You don’t really
know what’s inside unless you dive into the void.

Lava caves, formed from cooled lava flows underground, are found near
shield, basalt volcanoes across Earth. These lava tubes should ideally be
found anywhere in the universe near basalt volcanoes, like on the moon or
Mars, but that notion has long been hypothetical — until now.

One such lava tube has been confirmed on the moon for the first time,
according to a recent study
<https://www.nature.com/articles/s41550-024-02302-y.epdf?sharing_token=4CuEhbY2umAdUm1kC3tyzNRgN0jAjWel9jnR3ZoTv0NM3XCoO8qqQAVpZqycEJ41v-Y1i8jue3aIH5QvXVkwNIDG05FT6TE18PXVjMFifFwk8AHUer-PGE2cY787xCwaKbaR74xKS1N4nyEeQYgPQ0AG6ZWZd_t2fo-oZCDz0hz36m8ZEy-9VO4jTzrt11yANW1ASYBU2f6fFZSIuuje1Q%3D%3D&tracking_referrer=www.cnn.com>.
These caves could shelter future human visitors and even harbor signs of
microbial life, scientists say. But to learn more about what these features
may look like on the moon, they’ve been studying similar lava tubes on
Earth.

“Everything that we learned and what we’re theorizing about the moon’s lava
tube comes from what we’ve seen here on Earth,” said Jekan Thanga, an
engineer at the University of Arizona who was not involved in the study.

>From a bird’s-eye view, evidence of a lava tube just appears as a hole on
the surface. The hole, known as a skylight, is an area where the tunnel
collapsed from above and provides access to the rest of the cave. Inside,
the tunnel is jet black because basaltic lava flows are dark, whereas more
familiar karst caves, for example, are made of lighter limestone. The sides
of the tunnel are smooth like glass, except where breakage has created
shards. The floor is like cobblestone because of rock that is half melted.

https://www.washingtonpost.com/climate-environment/2024/09/06/lava-caves-moon-earth/