Does the moon have Intercrater Plains?

Unmasking the Moon: Are There Really Intercrater Plains Up There?

The Moon. Just the word conjures up images of a silvery orb hanging in the night sky, a constant companion to our planet. We all know it’s covered in craters, right? But what about those smoother patches nestled between all those impact scars? Are those what scientists call “intercrater plains”? Let’s dive in and see what lunar geology has to say.

So, What Exactly Are Intercrater Plains?

Think of intercrater plains as the filling in the gaps. On a heavily cratered surface, these are the relatively smooth areas that sit between all the pockmarks. You’ll often find them peppered with smaller craters, and they tend to bury or soften the edges of older, smaller craters. What they’re really telling us is that something happened to resurface the area after the initial, crazy-intense bombardment phase of the early solar system.

The Moon’s Highlands: Intercrater Plains in Disguise?

Now, you might hear “intercrater plains” more often when folks are talking about Mercury. But guess what? The Moon has similar features, especially in its highlands. These highlands make up a whopping 80% of the lunar surface, and they’re absolutely covered in craters. But look closely, and you’ll spot those smoother areas tucked in between. In a way, you could think of them as the Moon’s version of intercrater plains.

How Did They Get There? The Mystery of Their Origin

This is where it gets interesting. How did these plains form? Well, scientists have a few ideas, and it’s likely a combination of factors.

• Volcanoes of the Past: Imagine ancient lava flows oozing across the surface, filling in the low spots between craters. Some believe this early volcanic activity, especially involving that weird KREEP stuff (potassium, rare earth elements, and phosphorus – lunar dirt!), played a big role.
• Impact Ejecta Blankets: Picture this: a massive asteroid slams into the Moon, sending debris flying everywhere. This debris, called ejecta, blankets the surface, filling in craters and creating those smoother plains. The Cayley Formation is one example, and some scientists think it’s basically a giant pile of ejecta from huge impacts. The Orientale basin, the youngest big impact basin on the Moon, might have been a major source.
• A Bit of Both, Perhaps? Honestly, it’s probably not just one thing. It’s likely that both volcanic activity and impact ejecta worked together to create these intercrater plains.

What are these plains made of? It depends on where you are on the Moon. The highlands are mostly anorthosite, a rock rich in calcium. The darker maria are basalt, like the stuff you find in Hawaii. And those intercrater plains? They might be a mix, including breccias – basically, rocks made of broken bits of other rocks.

Ancient History Etched in Stone

These intercrater plains are seriously old. They go way back to the Moon’s early days, even before those dark lava flows created the maria. By studying the number and size of craters on these plains, scientists think that they buried craters smaller than about 30 km in diameter. The time between 3.8 billion and 1 billion years ago is super important for understanding how often the Moon was getting hit by space rocks.

Don’t Confuse Them with Smooth Plains!

Now, don’t go mixing up intercrater plains with smooth plains. Smooth plains are usually found inside impact basins, and they’re generally thought to be volcanic. They’re also smoother and have fewer craters than intercrater plains.

The South Pole’s Secret Plains

Even the Moon’s south pole has its own version of these plains. Some scientists think the light plains there are actually layers of ejecta from multiple impacts that happened around 3.8 billion years ago. It looks like the ejecta from the Schrödinger basin might have ended up there.

So, the Verdict?

Okay, so the Moon might not have exactly the same kind of intercrater plains as Mercury. But it does have similar features tucked away in its highlands. These plains probably formed from a mix of ancient volcanoes and debris from massive impacts. By studying them, we can unlock secrets about the Moon’s past and the wild early days of our solar system. And that’s pretty cool, right?