Transcript for the Weekend of October 11th

STEVEN
Welcome to Idaho Skies for the weekend of October 11th. We’re your hosts, Steven...

BENJAMIN
...and Benjamin.

PAUL
Hey, the moon is full on Sunday the 13th. That makes this weekend a great time to learn about the difference between lunar maria and highlands. 

STEVEN
Current understanding suggests that the moon, or Luna, formed after the impact of a Mars-sized object with the newly born Earth. Since the impact was glancing, it blasted a lot of Earth’s outer layer, or mantle into space. The minerals in the mantle rock tend to have a low density.

BENJAMIN
The vaporized rock the impact let in orbit around Earth was low in iron. That created a moon that was light whitish in color, once it cooled, that is. We see this material in in the brighter parts of the moon. And since it originated with the impact, lunar areas that are brighter in color are around 3.8 billion years old.

STEVEN
Three point eight billion years ago, the solar system was still swarming with planetary building blocks, or planetesimals. These giant meteoroids occasionally slammed into the moon creating huge craters called impact basins. Impact basins also deeply cracked the lunar crust. 

BENJAMIN
After the moon’s surface cooled, its interior remained warm. Partly from the initial impact but also from radioactive decay. The warm interior created magma or lava that welled up into the impact basins. Layer after layer of dark lava filled the impact basins to create mostly dark circular features.

PAUL
So the moon started out as a light-colored body that was repeatedly smashed in horrific impacts. These then filled in with darker lava to create the lunar seas and the Man-on-the-Moon face we enjoy today.       

STEVEN
That’s Idaho Skies for the weekend of October 11th. 

BENJAMIN
Be sure to read our blog for additional information. It’s at idahoskies.blogspot.com

For Idaho Skies this is Benjamin...

STEVEN
...and Steven.

BENJAMIN
Dark skies and bright stars.