
Click the link below the picture
.
When University of Maryland physicist Timothy Koeth received a mysterious heavy metal cube from a friend as a birthday gift several years ago, he instantly recognized it as one of the uranium cubes used by German scientists during World War II in their unsuccessful attempt to build a working nuclear reactor. Had there been any doubt, there was an accompanying note on a piece of paper wrapped around the cube: “Taken from Germany, from the nuclear reactor Hitler tried to build. Gift of Ninninger.”
Thus began Koeth’s six-year quest to track down the cube’s origins, as well as several other similar cubes that had somehow found their way across the Atlantic. Koeth and his partner in the quest, graduate student Miriam “Mimi” Hiebert, reported on their progress to date in the May issue of Physics Today. It’s quite the tale, replete with top-secret scientific intrigue, a secret Allied mission, and even black market dealers keen to hold the US hostage over uranium cubes in their possession. Small wonder Hollywood has expressed interest in adapting the story for the screen.
Until quite recently, Koeth ran the nuclear reactor program at UMD, which is how he met his co-author. Hiebert is completing a Ph.D. in materials science and engineering, specializing in the study of historical materials in museum collections (glass in particular) and the methods used to preserve them, using the reactor facility for neutron imaging of a few samples. Koeth told her about his research into his cube’s origins, and she started collaborating with him as a side project.
A quest for cubes
So far they have tracked down ten cubes around the US. For instance, the Smithsonian Institute had a German uranium cube in storage. “We wound up in a warehouse that looked like the final scene in Raiders of the Lost Ark, wooden crates from floor to ceiling,” said Koeth. “And in one of those crates, there was another German cube.” There was also a piece of uranium from the original Chicago Pile-1—the first sustained nuclear chain reaction achieved by US physicists. They tracked a third cube to Harvard University, where it regularly gets passed around to students in introductory physics classes as a curiosity. (The cubes are only slightly radioactive and don’t pose a health concern, according to Koeth. Since uranium is so dense, “It winds up shielding itself,” he said. “The radiation you measure from it is only coming from the surface.”)
.

This is likely one of 664 uranium cubes from the failed nuclear reactor that German scientists tried to build in Haigerloch during World War II.Photo by John T. Consoli/University of Maryland.
.
.
Click the link below for the article:
.
__________________________________________
Leave a comment