Japanese officials said nuclear fuel rods appear to be melting inside all three of the damaged reactors at the Fukushima Daiichi plant. Chief Cabinet Secretary Yukio Edano: "Although we cannot directly check it, it's highly likely happening." The plant suffered its second reactor explosion in three days on Monday as technicians frantically tried to jury-rig a new cooling system. Operators have resumed pumping seawater into reactor 2, but fuel rods may have been exposed for more than two hours after the pump's fuel ran out. Full meltdowns, in which molten nuclear fuel melts its way through containment vessels, could release catastrophic amounts of radiation, putting first responders and those attempting to fix the problem in even more danger. However, according to the BBC, experts say a Chernobyl-scale disaster is unlikely "because the reactors are built to a higher standard and have much more rigorous safety measures." What happens when those safety measures fail? We may be about to find out.
The scary developments in Japan have prompted some excellent explanations of nuclear power and the dangers posed by the damaged Fukushima Daiichi reactors — especially useful for those of us whose knowledge is limited, as Boing Boing's Maggie Koerth-Baker noted, to what we've seen on The Simpsons.
The Boing Boing post gets extra-credit points for using a helpful Jenga analogy to describe nuclear fission. Alby Reid, a physics teacher at MrReid.org, also has a clear-headed breakdown of what's going on, and argues that "Fukushima will not be 'another Chernobyl.'"
*Stay tuned for updates.
Situation at Fukushima nuclear power station [MrReid.org]
Nuclear energy 101: Inside the "black box" of power plants [Boing Boing]
All about nuclear meltdowns[kottke]
Second Explosion at Reactor as Technicians Try to Contain Damage [NYT]
Meltdown alert at Japan reactor [BBC]
Official: Rods likely melting in Japanese reactors [AP via Dallas Morning News]