VISUAL ARCHIVE / IMAGE STORY
Ancient Stars as Cosmic Clocks
Some of the Milky Way’s oldest surviving stars carry a record of almost the entire history of the universe. Their estimated ages are becoming a difficult test for cosmological models that leave less time for them to exist. AI-generated conceptual illustration.
Some of the Milky Way’s oldest surviving stars carry a record of almost the entire history of the universe. Their estimated ages are becoming a difficult test for cosmological models that leave less time for them to exist. AI-generated conceptual illustration.
THE OBSERVATION
What we can actually see.
Stellar ages are inferred from observables such as luminosity, temperature and composition using evolutionary models. Cosmological ages are also model-dependent inferences, and changing the expansion history changes the time available for stellar evolution.
THE ILLUSTRATION
What the artwork imagines.
Some of the Milky Way’s oldest surviving stars carry a record of almost the entire history of the universe. Their estimated ages are becoming a difficult test for cosmological models that leave less time for them to exist. AI-generated conceptual illustration. The selected artwork is a conceptual reconstruction. Viewpoint, lighting and apparent detail are illustrative, not additional measurements or a confirmed photograph of the depicted event.
FROM THE ILLUSTRATED ARTICLE
The story that inspired it.
Long-lived stars offer a test of proposed changes to cosmic history. Their inferred ages must be compared with cosmological ages while accounting for model assumptions and the time before stars formed.
Read The Oldest Stars May Be Too Old for a Younger UniverseCHECK THE RECORD
The image interprets the research below. Follow the original work for the measurements and limits behind the scene.
Banik, I., Kudakolawa Kaluarachchige, T., Cookson, S. and Desmond, H. — The age of the Universe from a large sample of the oldest Galactic stars Xiang, M. and Rix, H.-W. — A time-resolved picture of our Milky Way’s early formation history Planck Collaboration — Planck 2018 results VI Cosmological parameters Riess, A. G. and colleagues — A Comprehensive Measurement of the Local Value of the Hubble ConstantOTHER IMAGE STORIES
A Spectrum Helps Estimate Stellar Age
The First Stellar Generations
The Mark Shared by Titan and Pluto