- By looking at three scales simultaneously, researchers can identify features of interest, such as the maria, which are smooth at large scales and rough at short scales; these features appear blue. The rough terrain of relatively young craters appears white, while basin ejecta—material thrown out of the large craters at the time of impact—has an orange color, meaning that this material is rougher at the large scale than at the small scale. The map is adapted from the Journal of Geophysical Research (2011) Credit: NASA/CalTech
Earth’s Moon is a tattered and cratered place…its face tells a tale that is some 4.5 billion years old.
Thanks to NASA’s Lunar Reconnaissance Orbiter (LRO), the first comprehensive set of maps revealing the slopes and roughness of the Moon’s surface have been pieced together.
That work has been led by Meg Rosenburg and her colleagues at the California Institute of Technology (CalTech) in Pasadena, California.
From impact craters to the dark plains of maria left behind by volcanic eruptions, the scars are all that remain to tell the tale of what happened to the Moon. But they only hint at the processes that once acted — and act today — to shape the surface.
The new maps are based on detailed data collected by the Lunar Orbiter Laser Altimeter (LOLA) on NASA’s LRO.
Both LRO and LOLA were built at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
“Old and young craters have different roughness properties…they are rougher on some scales and smoother on others,” CalTech’s Rosenburg said in a press statement. “That’s because the older craters have been pummeled for eons by meteorites that pit and mar the site of the original impact, changing the original shape of the crater.”
Just as on the moon, the same approach can be used to study surface processes on other bodies as well, Rosenburg added. “The processes at work are different on Mars than they are on an asteroid, but they each leave a signature in the topography for us to interpret.”
Rosenburg said that by studying roughness at different scales, scientists can begin to understand how our nearest neighbors came to look the way they do.
NASA’s LRO was launched on June 18, 2009.
By Leonard David