Jabba eyed the VR. “PEM authorization’s going fast. Last line of defense. And there’s a crowd at the door.”
“Focus!” Fontaine commanded.
Soshi sat in front of the Web browser and read aloud. . .Nagasaki bomb did not use plutonium but rather an artificially manufactured, neutron‑saturated isotope of uranium 238.”
“Damn!” Brinkerhoff swore. “Both bombs used uranium. The elements responsible for Hiroshima and Nagasaki were both uranium. There is no difference!”
“We’re dead,” Midge moaned.
“Wait,” Susan said. “Read that last part again!”
Soshi repeated the text. “. . .artificially manufactured, neutron‑saturated isotope of uranium 238.”
“238?” Susan exclaimed. “Didn’t we just see something that said Hiroshima’s bomb used some other isotope of uranium?”
They all exchanged puzzled glances. Soshi frantically scrolled backward and found the spot. “Yes! It says here that the Hiroshima bomb used a different isotope of uranium!”
Midge gasped in amazement. “They’re both uranium‑but they’re different kinds!”
“Both uranium?” Jabba muscled in and stared at the terminal. “Apples and apples! Perfect!”
“How are the two isotopes different?” Fontaine demanded. “It’s got to be something basic.”
Soshi scrolled through the document. “Hold on . . . looking . . . okay . . .”
“Forty‑five seconds!” a voice called out.
Susan looked up. The final shield was almost invisible now.
“Here it is!” Soshi exclaimed.
“Read it!” Jabba was sweating. “What’s the difference! There must be some difference between the two!”
“Yes!” Soshi pointed to her monitor. “Look!”
They all read the text: . . .two bombs employed two different fuels . . . precisely identical chemical characteristics. No ordinary chemical extraction can separate the two isotopes. They are, with the exception of minute differences in weight, perfectly identical.
“Atomic weight!” Jabba said, excitedly. “That’s it! The only difference is their weights! That’s the key! Give me their weights! We’ll subtract them!”
“Hold on,” Soshi said, scrolling ahead. “Almost there! Yes!” Everyone scanned the text. . .difference in weight very slight . . .gaseous diffusion to separate them . . .10,032498X10?134 as compared to 19,39484X10?23.** “There they are!” Jabba screamed. “That’s it! Those are the weights!”
“Go,” Fontaine whispered. “Subtract them. Quickly.”
Jabba palmed his calculator and started entering numbers.
“What’s the asterisk?” Susan demanded. “There’s an asterisk after the figures!”
Jabba ignored her. He was already working his calculator keys furiously.
“Careful!” Soshi urged. “We need an exact figure.”
“The asterisk,” Susan repeated. “There’s a footnote.”
Soshi clicked to the bottom of the paragraph.
Susan read the asterisked footnote. She went white. “Oh . . . dear God.”
Jabba looked up. “What?”
They all leaned in, and there was a communal sigh of defeat. The tiny footnote read: **12% margin of error. Published figures vary from lab to lab.