Washington Post: Last April in the Czech capital of Prague, US President Obama and Russian President Dmitry Medvedev signed a new nuclear weapons treaty. Neither the US Senate nor the Russian Duma has ratified the treaty. As Mary Beth Sheridan and Walter Pincus of the Washington Post report, Senate ratification appears to hinge on the views of one senator, Republican Jon Kyl of Arizona. He is insisting that the new treaty be accompanied with $4 billion of additional funding to modernize the US nuclear arsenal. Kyl’s influence is particularly potent because few of his fellow Republicans have taken an interest in nuclear weapons. If the treaty remains unratified, neither the US nor Russia is obliged to limit its nuclear weapons or allow its nuclear facilities to be inspected. That’s because the previous treaty, the Strategic Arms Reduction Treaty, expired in December 2009.
The finding that the Saturnian moon may host layers of icy slush instead of a global ocean could change how planetary scientists think about other icy moons as well.
Modeling the shapes of tree branches, neurons, and blood vessels is a thorny problem, but researchers have just discovered that much of the math has already been done.
January 29, 2026 12:52 PM
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