Earth's Moon: Still A Puzzle: Paul Lowman, a planetary geologist at NASA's Goddard Space Flight Center in Greenbelt, Maryland: "'I think the origin of the Moon is still an unsolved problem, contrary to what anybody will tell you,' Lowman said.

"Lowman said that there is a treasure trove of data still to be plumbed from data acquired decades ago during the Apollo program. For instance, he has been taking another look at images snapped by moonwalkers from the Apollo 15, 16, and 17 landings, finding evidence for layered structure in lunar highland crust.

"Working with Tiffany Yang, a research colleague, Lowman has reviewed hundreds of lunar surface shots, identifying layers in the surrounding terrain that are not explainable as overlapping layers of ejecta from craters or mare basins. He reported here at the LPSC that this pervasive layering is the expression of lava flows.

"'Data has been sitting around and never properly studied. We were overwhelmed by the information from Apollo. People never went back to it,' Lowman said. Thanks to new and better techniques, like digital processing, giving Apollo-era pictures and other data another look can prove valuable, he said."