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Scientists opened a sealed envelope after 10 years. Gravity still didn’t make sense
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Scientists discover a hidden “ID card” in cat urine
Cats may identify one another through a surprisingly durable chemical “calling card” made from 13 unusual fatty acids in their urine. The compounds appear linked to mysterious fat droplets in the kidneys and may represent a scent-recognition system shared across the cat family.
Scientists may have solved a 2,000-year-old Dead Sea Scrolls mystery
Researchers may have solved a long-running mystery surrounding the Dead Sea Scrolls by proposing that the Qumran sect really did use its distinctive 364-day calendar. Its perfectly ordered 52-week system kept holidays on the same weekdays, but it slowly drifted out of sync with the seasons because it was shorter than the true solar year.
New nanoparticles make hidden chemical differences light up
Scientists have developed ultra-bright nanoparticles that can detect tiny amounts of chemicals and distinguish between molecules that look almost identical. The technology could one day provide a cheaper way to catch dangerous drug impurities or trace pollutants using simple low-cost lasers.

New £1m grant to help groups protect green spaces
The cash can be used by local communities to protect threatened green spaces and wildlife sites.
Ancient DNA reveals how plague kept returning for 400 years after the Black Death
Ancient DNA reveals that plague repeatedly returned to Europe for more than 400 years after the Black Death, evolving into new lineages and spreading through trade, migration, and war. Researchers also developed a method to date ancient plague genomes more precisely, linking many of them to specific outbreaks recorded in historical sources.

'You never quite know what you're going to pull out'
The group is marking a decade of fishing everything from an inflatable doll to a Nintendo out of the harbour.