Science Stories with Joe Johnson: Taming Nuclear Waste, Hunting Sunken Treasure, and Cockroaches in Love

Our resident science guy Joe Johnson brings us stories that caught his eye recently:

Can particle accelerators make nuclear waste safe in 300 years?

Spent nuclear fuel rods remain dangerously radioactive for an estimated 100,000 years — longer than all of recorded human history combined. A new Department of Energy research program wants to change that.

Commercial nuclear reactors generate electricity by splitting uranium-235 atoms to produce heat. The fuel rods that contain the uranium typically last three to six years before too much of the U-235 has transmuted into other radioisotopes — including plutonium and americium — to remain useful. The rods are then replaced. What remains is still intensely radioactive; it just can’t generate power anymore.

The target: reduce nuclear waste’s hazardous storage requirement from 100,000 years to as little as 300.

Researchers at the Thomas Jefferson National Accelerator Facility and Oak Ridge National Laboratory are investigating whether particle accelerators could transmute those long-lived isotopes into shorter-lived, more manageable materials. The proposed method fires high-speed protons into mercury, producing a neutron stream that would then be directed into spent fuel — changing its isotopic makeup into forms that either decay within a 300-year window or could be repurposed for uses like cancer research, sterilization, or medical diagnostics.

Scientific details from the program remain limited at this stage. Results are pending.

The San José: a $20 billion shipwreck and four competing claims

On June 8, 1708, the Spanish galleon San José — flagship of a treasure fleet loaded with gold, silver, emeralds, and jewelry — was attacked by British warships in the Caribbean. Its gunpowder stores exploded, sinking the ship in roughly 2,000 feet of water off the coast of Cartagena, Colombia. Only 11 of approximately 600 crew survived.

The cargo has been valued at between $17 billion and $20 billion today, making the San José what many archaeologists call the richest shipwreck ever discovered. It has also attracted one of the most complex ownership disputes in maritime history.

Four parties are asserting claims. An American salvage company — the same firm that located the famous Atocha wreck — says it found the San José in 1981 and is seeking 50 percent of its value. Colombia, citing the wreck’s location in its territorial waters, has declared the site a national cultural interest and documented it using remotely operated vehicles in partnership with the Woods Hole Oceanographic Institution. Footage shows stacked coins, cannons, and dozens of intact porcelain teacups — the wooden crates that held them long since decayed. Spain argues ownership on the grounds that the San José was a sovereign warship. And an indigenous Bolivian group contends that a share belongs to the descendants of enslaved ancestors who mined the treasure.

Courts in multiple countries are weighing claims on a wreck that has sat undisturbed for more than 300 years.

Colombia has already recovered several artifacts: a bronze cannon with identifying markings that confirm the wreck’s identity, three hammered gold coins called macuquinas minted in Lima in 1707, and one porcelain teacup. More recoveries are planned, pending the outcome of ongoing legal proceedings.

Scientists confirm pair bonding in an insect — the Japanese wood cockroach

Lifelong pair bonding is well established in vertebrates — bald eagles, penguins, wolves, beavers, swans, and even some fish. Among invertebrates, it has been almost entirely undocumented. A study in the March 4 issue of Royal Society Open Science changes that.

The subject is Salganea taiwanensis, a black, one-inch Japanese cockroach that lives in and feeds on rotting wood. After leaving their birth colonies to find mates, newly adult pairs do something unusual: they eat each other’s wings, a process that can take several days. Researchers believe the behavior may ease movement through tight tunnels in decaying logs and may create a chemical bond between partners. The wingless pair then build a nest together, groom each other regularly, and raise offspring — apparently for life.

To test the strength of that bond experimentally, researchers placed post-wing-eating pairs in a test arena and introduced an unmated intruder from another colony. The bonded pairs responded with clear aggression: abdominal waggling and repeated physical ramming. Pairs that had not yet completed the wing-eating ritual were significantly less defensive. The data confirm what field observation had suggested — the wing-eating is not incidental. It is the commitmen

Image: Two wood-feeding cockroaches (Salganea taiwanensis). The one on the left is missing it’s wings after the mutual wing-eating behavior. The one on the right has it’s wings intact. Haruka Osaki and Eiiti Kasuya