Overview
- The TDCOSMO team reports H0 = 71.6 kilometers per second per megaparsec with +3.9/−3.3 uncertainty from eight gravitationally lensed quasars.
- This value agrees with late‑universe distance‑ladder results and conflicts with early‑universe CMB inferences near 67 km/s/Mpc.
- Time‑delay cosmography infers distances by measuring arrival‑time differences among multiple quasar images and modeling the lens galaxy’s mass distribution.
- The analysis incorporates new observations from JWST, the Keck Observatory, and the Very Large Telescope, and is published in Astronomy & Astrophysics.
- Researchers plan to expand the lens sample and refine mass modeling to reach ~1–2% precision, with further Keck observations slated to improve constraints.