Could the moon have had large fountains of fire on its surface? Doesn't fire need oxygen to fuel it? Since there's no oxygen on the moon, where would the fire come from? Large dark mantle deposits and glass beads like those from a volcano were discovered on the moon when astronauts landed on it. Clearly there was fire of a sort once on the moon, most likely from volcanic eruptions. But when was this and how did it happen?
Scientists have researched the moon's former fire fountains for years, trying to determine their origin. Now they think they may have found it, and the key is carbon monoxide. Since the moon has no atmosphere, there isn't any carbon monoxide currently there. But when the moon was created, which is currently thought to have happened when a large object hit a young Earth, it was still Earth-like, and had volcanic activity. The carbon-dense magma that came to the surface had carbon monoxide in it, but most of the gas bubbled to the surface before the magma did. Eventually, the magma exploded at the surface into volcanic fountains of fire.
In 2008, traces of water were found on the moon. Fire fountains on Earth are propelled by water, which combines with carbon dioxide to make an explosive hydrogen gas. Although this was the first clue for solving the mystery of the moon fire fountains, the question of where the hydrogen came from remained until glass samples brought back from the Apollo missions were re-analyzed with an ion probe that could detect extremely low levels of carbon. The glass was found to contain carbon, revealing where the fire fountains had obtained the hydrogen. (Thus, carbon monoxide was created on the moon due to the differences in the surfaces of the Earth and the moon.)
The process is still visible on Earth today; fire fountains in the Holuhraun valley in Iceland are very similar to those once on the moon and are still erupting. The most famous of the Holuhraun fire fountains is the one that unleashed a massive ash cloud in 2010 and grounded flights all over Europe. The magma is doused in water from the ice that covers it, leading to vast explosions of fire at the surface. When the magma explodes under the ice, ash clouds result from the steam created by the melted ice. Iceland sits on a tectonic plate, which leads to the volcanic activity and subsequent fire fountains in the area. There's no need to travel to the moon to see the remains of fire fountains.
[Photo via Wikipedia/Peter Hartree]