In October, international timekeeping authorities are set to vote on the future of the leap second, the occasional one-second adjustment used to keep atomic time aligned with the Sun. The debate over the leap second comes as subtle shifts in Earth’s rotation complicate how we keep clocks in sync.
Leap second
Since the 1970s, timekeepers have inserted a leap second when needed so that highly stable atomic clocks do not drift from solar time. According to metrology experts, recent changes in Earth’s rotation are making these corrections more complex, raising the possibility that the long-standing system could be overhauled.
A visit to the National Physical Laboratory highlights how precision timing underpins everything from GPS to financial trading. Principal scientists there explain how even a one-second tweak can ripple through navigation systems, telecom networks, and data centers.
Researchers note that as Earth’s rotation has recently sped up, the schedule for adjustments can become unpredictable for the systems that rely on uniform time.
Geophysicists point to processes inside our planet that influence rotation, including interactions between the core and mantle, as well as mass shifts in the oceans and atmosphere. These natural variations affect the length of a day at the millisecond level, which, over time, can nudge atomic and solar time out of alignment.
Hot science headlines on complex life
This week’s science highlights include new insights into the body temperature of Tyrannosaurus rex gleaned from fossil chemistry, and research probing the highest temperatures that complex life, or eukaryotic cells, can tolerate. Both studies shed light on the extremes life can endure, with implications for understanding ancient ecosystems and the boundaries of habitability.
Related work on heat tolerance in eukaryotes includes discoveries such as the “fire amoeba” that set a new heat tolerance record for complex life, expanding what scientists consider possible for living systems.
Award season for science writing
With the Royal Society Trivedi Book Prize winner set to be announced next week, author and judge Bill Bryson shared why the award remains a favorite among science writers and readers. Shortlisted author Lise Barnéoud discussed her book Hidden Guests, which explores microchimerism, the presence of cells in our bodies that originate from other individuals, and what that means for health and identity.
For more on these topics, science producers and presenters encourage listeners to dive deeper through related educational resources and program guides.
