nuclear arsenals

Name: Cielo

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Vital Stats: System: Cray XE6 8-core 2.4 GHz running Linux. Processors: AMD x86_64 Opteron 8 Core 2400 MHz (9.6 gigaflops). Sustained performance: 1.11 petaflops. The hardware takes up about 1,500 square feet but uses less than 4 megawatts of energy. The system consists of 96 cabinets with nearly 9,000 compute nodes and approximately 300 terabytes of memory.

Thanks to threats from North Korea, an experimental missile shield and radar system may be deployed to Hawaii before testing has been completed. After North Korea’s recent nuclear test and vague threats of launching another Taepodong-2 missile towards Hawaii, the Pentagon has decided to rush the still-in-development Army Terminal High-Altitude Air Defense missile systems and the SBX x-band radar into action. Although the technology has existed for many years it may finally get its first test in real-world conditions.

U.S. nuclear warheads might have been technological marvels a half-century ago, but today they're akin to a fleet of '57 Chevys — at least according to those who say the U.S. arsenal is begging to be traded in for a new model called reliable replacement warheads, or RRW.

For the last half-century, the U.S. has maintained its 5,400-warhead arsenal by replacing degraded plastic and rubber parts. But the most important part of the warhead — its explosive radioactive core — naturally decays over time and has not been replaced.

The warheads will remain dependable for at least 82 more years, or until the year 2091, according to a 2006 report by JASON, an independent scientific advisory group for the U.S. government. At that point, the warheads’ decayed cores could leave the U.S. with an impotent nuclear arsenal. "The concern is, can we keep the nuclear arsenal safe, reliable and effective for as long as we’ll need nuclear forces?" says John R. Harvey, a physicist in the U.S. Department of Energy’s National Nuclear Security Administration.

So what about 2004 MN4, that hunk of rock hell-bent for Earth?