, A. Koekemoer , R. Windhorst , and Z. Levay )is a Professor of Astronomy & Astrophysics at UC San Diego, and an observational astrophysicist investigating the coolest stars, brown dwarfs and extrasolar planets.
Measuring the ages of planets and stars helps scientists understand when they formed and how they change – and, in the case of planets, ifDetermining the age of a star or planet can be as hard as guessing the age of a person who looks exactly the same from childhood to retirement., similar to how a spinning wheel slows down when it encounters friction.
Our own solar system provides the best check for accuracy, since astronomers can compare the radionuclide ages of rocks on the Earth, moon, orare believed to have all formed at roughly the same time, so age estimates for individual stars in these clusters should be the same. In some stars,radionuclides like uranium – a heavy metal found in rocks and soil – in their atmospheres, which have been used to check the ages from other methods.
Astronomers believe planets are roughly the same age as their host stars, so improving methods to determine a star’s age helps determine a planet’s age as well. By studying subtle clues, it’s possible to make an educated guess of the age of an otherwise steadfast star.