Draw down the moon dating america dating directory
20-Sep-2020 03:42
This map of lunar crustal thickness was derived from an analysis of GRAIL's gravity data.
It lists the basins from oldest to youngest, based on crater counting -- basins with more, bigger craters on top of them are older.This is all part of the work geologists are doing right now -- sorting out the order of events in the history of the moon and other solid-surfaced worlds in the solar system, trying to understand our origin story.Fascinating stuff, and I'll have more to say about this work in later posts.Other names are unfamiliar; these are the basins that were not obvious until we got topography and gravity data. Which one happened first, and which one happened later? What order the lunar basins formed in is a question I have a lot when looking at these global maps of the Moon, and I hadn't found an online resource for it.
Often, these previously hidden basins are named by mentioning two craters or other features that occur on their edges -- things like Freundlich-Sharonov and South Pole-Aitken. So I am hereby making one, based on a new paper that's in press in the by Caleb Fassett, Jim Head, and another five coauthors: "Lunar impact basins: Stratigraphy, sequence and ages from superposed impact crater populations measured from Lunar Orbiter Laser Altimeter (LOLA) data." The paper contains a table that tells us the relative ages of many of these basins -- which ones came first and which ones came later.
I will climb back out of the rabbit hole eventually with lots of good stories about the geology of many different planets, but I'm going to have to tell those stories bit by bit.