Though we focus pretty heavily on craters here at CosmoQuest, we also encourage marking of any unusual features on the surfaces of the Moon, Vesta, and Mercury. Sometimes you can give a descriptor, such as “bright albedo feature” or “boulder field.” Other times, you just see something… weird. Mark it as an unusual feature, because you never know what interesting science can come of it!
One such “unusual feature” spotted in the Apollo 15 photography was dubbed “Ida” and remained a one-of-a-kind mystery for some time. Images from the Lunar Reconnaissance Orbiter (LRO) have shown more odd features like Ida with sharp edges, weird coloring, and very little cratering. 70 of these irregular volcanic features have now been identified in LRO images. Now called irregular mare patches, these are probably evidence of recent volcanism on the Moon! Well, by recent we mean less than 1 billion years ago when volcanism was thought to have abruptly stopped on the Moon. Instead, some of these volcanic features may be less than 100 million years old, suggesting that the Moon still had some volcanic activity while the dinosaurs were roaming the Earth.
So keep your eye out for weird features, and keep counting craters! Remember, much of what we know about lunar surface ages comes from this method, and you’ve already proven yourselves to be expert Moon Mappers.