Japan Reactors, Seen From Space
Satellite image from DigitalGlobe/Getty Images
A plume of white steam billows from ruined reactor 3 (the second structure from the left) at Japan's Fukushima Daiichi nuclear power plant, as seen in a Wednesday satellite image—two days after an explosion blew the roof off the unit's secondary containment building.
Varying levels of damage are visible in the all four reactor units at left, while the two tall white rectangular structures at right, reactor buildings 5 and 6, remain intact.
Authorities on site are resorting to ever more desperate measures to quell the worst nuclear crisis in 25 years, which began after Japan's recent earthquake and tsunami resulted in loss of power to the generating station's crucial cooling systems.
To avert a catastrophic meltdown, authorities have tried dropping water from helicopters and shooting it from military trucks' water cannons. But radiation levels are creating peril for workers, and residents within a 12-mile (20-kilometer) radius have been evacuated. U.S. officials have urged a wider evacuation area and warn that it could take weeks to get the crisis under control.
Published March 18, 2011
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Reactor Units 4, 3, 2, 1
Satellite image from DigitalGlobe/Getty Images
The rectangular buildings housing reactor units 4, 3, 2, and 1 (left to right) show varying levels of damage at Japan's Fukushima Daiichi nuclear plant on Wednesday. In each building, after cooling systems had failed, fuel rods began heating up, spurring explosions in spaces between the reactor itself and the building's exterior walls.
Unit 4's roof (far left) appears intact, but much of the building's sides were destroyed March 15, when chemical reactions with spent fuel rods likely sparked hydrogen-gas explosions and fires, according to the New York Times.
At Unit 3, pictured spewing white steam, a March 14 blast wrecked the building and harmed the steel containment vessel around the nuclear reactor itself.
At Unit 2—appearing the least damaged but with an exterior panel likely removed to vent steam, according to the Institute for Science and International Security—a March 15 explosion likely compromised the reactor's primary containment shell.
At Unit 1 (far right) a March 12 blast destroyed roughly the top third of the building.
Published March 18, 2011
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Before the Blasts
Satellite image from DigitalGlobe/Getty Images
No visible external damage is apparent in a March 12 satellite image of Japan's Fukushima Daiichi nuclear power plant—the day after the magnitude 9 earthquake and tsunami.
Later that day, though, high heat around the reactor in Unit 2 (second from right) helped set off the first major explosion of the Fukushima crisis, blowing the roof off the building.
Published March 18, 2011
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Fukushima Daiichi Before Quake
Photograph from Kyodo/Reuters
Pictured in October 2008, Japan's Fukushima Daiichi nuclear power plant has operated since the 1970s but now appears destined for infamy alongside Ukraine's Chernobyl and Pennsylvania's Three Mile Island.
Japanese authorities have set a 12.5-mile (20-kilometer) evacuation zone because of raised radiation levels and are urging people to say indoors within 19 miles (31 kilometers) of the plant.
The U.S. State Department on Wednesday took a more cautious view, urging all Americans to evacuate areas within 50 miles (80 kilometers) of the reactors.
Published March 18, 2011
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Nuclear Plant, Just After Blast
Satellite image from DigitalGlobe/Getty Images
Pictured just a few minutes after an explosion on March 14, the thick plumes extending over the Pacific are mainly smoke and dust from the blast, rather than steam from the reactor, the Institute for Science and International Security speculated.
On March 18—even as water cannons continued to fire on the reactors—the fight to cool Fukushima Daiichi had a new focus: running power cables to the reactor buildings, which might allow workers to restart cooling systems, Australia's ABC News reported.
The work could be completed this weekend, officials say. But experts say that restoration of power may not be enough to get cooling to the radioactive fuel, as the pumps and piping systems may have sustained damage from the earthquake, the tsunami, the explosions, or all three.
Published March 18, 2011
Thanks to News National Geographic
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