Hiroyuki Tanaka of the University of TokyoFriday August 10th, 2018 TechBB media Comments Off on Hiroyuki Tanaka of the University of TokyoHiroyuki Tanaka of the University of Tokyo reasoned that the throat could be “x-rayed” with energetic muons produced in cosmic-ray showers. The number of muons passing through the volcano would depend on the density of intervening rock, so measuring the number of muons passing through various parts of the volcano could yield a crude, 3-D view of the interior.