How Did I Miss That?
Welcome to Episode 13,
Houston, We Have a Volcano!
I’m Lisa Blank and this is How Did I Miss That?
I love space…the personal kind and also the outer kind. It was always my favorite topic in science class and I’m pretty sure I had a few space posters in my room as a kid. I’ve also always been fascinated by the moon. I remember being in the car with my parents and staring up trying to find the man in the moon, wondering exactly what I was looking at and probably thinking the darker spots were craters. Back then we didn’t have the internet to immediately quench our thirst for knowledge and flipping through encyclopedias wasn’t exactly my idea of a good time. The other day I came across something I had never heard about our bright light at night…there were active volcanoes on the moon when dinosaurs were alive. What? First of all, how did I miss that there were volcanoes on the moon? And B, though I know dinos lived a very long time ago, in relation to the age of the earth and moon, it was like minute ago. So how was the moon still active at the time of the terrible lizards? I bet you can guess what happened next. Yep, I jumped down the black rabbit hole of the interwebs…here’s what I found out.
Scientists have long known, or at least speculated, that there was volcanic activity on the moon, going back to even the 1600s. What Galileo thought were seas in 1610, were later suggested to be volcanoes by British chemist Robert Hooke in 1665. What both men were seeing in their telescopes were the bowl-shaped depressions of lunar lava plains. These lava plains cover approximately 15% of the moon’s surface and can be seen from earth as dark spots, leading the young and the old to see a man in the moon. They are made of basalt that has been dated using 2 different techniques. It was determined that the eruptions from the moon’s volcanoes occurred on average around 3 to 3.5 billion years ago. I know what you’re thinking…but Lisa, you told us that dinosaurs were around to possibly see the moon blow its top! I’m getting there…be patient. I only have about 2.5 billion more years of history to research.
Continuing down the black hole of my research, I found this particularly interesting though. The volcanic eruptions that occurred on the far side of the moon are older that the ones that have been found in the Oceanus Procellarum on the near side. And apparently scientists are still in debate over the reason for this phenomenon. Maybe one day we’ll have an answer, but not in time for this podcast release.
Something else that caught my attention was the fact that lava tubes have been found on the surface of the moon. Avid listeners of my little production might remember a previous episode about the lava tubes in Hawaii. I do love a good overlap of information that I’ve learned.
But back to T-Rex and his friends…
During the Apollo 15 mission in 1971, while orbiting the moon, astronauts photographed what looked like the aftermath of a volcanic eruption. The geological formation was named Ina by researchers. Originally, Ina wasn’t considered anything special. Afterall, scientists had known about volcanoes on the moon for years at this point. What they found strange was that Ina looked newer than other lava plains and depressions on the surface.
My first thought and maybe yours was how can they tell? Well, I have an answer for that, too. Since the moon’s crust is not made up of plates like the earth’s, it does not undergo plate tectonics and therefore the surface hasn’t changed significantly over time. This allows us to estimate the age of a geological feature like Ina by counting the number of craters on its surface. The moon is constantly being pelted with meteoroids, so more craters equal older landscape.
In 2014, NASA released a new discovery about the age of volcanic activity on the moon. Since the 1971 Apollo mission, researchers using NASA’s Lunar Reconnaissance Orbiter have found over 70 more landscapes similar to Ina that are only lightly cratered. This implies that they are less than 100 million years old. Remember, originally it was thought that volcanic activity had ceased around 3 billion years ago. And we’re finally here…this discovery leads us to believe that the volcanoes were most likely erupting on the moon while T-Rex was wreaking havoc on earth during the Cretaceous period. Researchers now believe that some of the volcanoes on the moon are even as young as 50 million years old. That’s when mammals started taking over as top dog on earth. It’s too bad volcanic activity has ceased on the moon. How cool would it be to look through a telescope and see a volcano erupt from that far away?!
Now whenever I look up at the moon, I definitely won’t being seeing it in the same light and hopefully neither will you.
Thanks for listening! If you like what you’re hearing, please make sure to share this podcast with all your friends and neighbors. And don’t forget to click follow or subscribe. Then join me every Tuesday and Friday as I uncover another interesting tidbit of knowledge and wonder… how did I miss that?!
