Describe Anything News

NO

NO

YES

15–19

10–14

5–9

20–24

30–∞

1–4

NO

No decision made in 2026 conference

Second defined by a (dynamic) weighted sum of atomic transitions

Second defined by a (fixed) weighted sum of atomic transitions

Second defined by 87Sr 698nm transition

Decision made to not redefine the second

Second defined by fixing the Rydberg constant

Second defined by 171Yb 578nm transition

Second defined by 199Hg 265nm transition

Second defined by 27Al+ 267nm transition

Second defined by 199Hg+ 282 nm transition

Second defined by 171Yb+ (E2) 436nm transition

Second defined by 171Yb+ (E3) 467nm transition

Second defined by 88Sr+ 674nm transition

Second defined by 88Sr 698nm transition

Second defined by 40Ca+ 729nm transition

Second defined by 87Rb 6.8GHz microwave transition

2026