We Just Got an Updated Estimate For The Age of The Milky Way

Like many other spiral galaxies in the Universe, the Milky Way Galaxy consists of two disk-like structures – the thin disk and the thick disk. The thick disk, which envelopes the thin disk, contains about 20 percent of the Milky Way's stars and is thought to be the older of the pair based on the composition of its stars (which have greater metallicity) and its puffier nature.

However, in a recent study, a team of 38 scientists led by researchers from Australia's ARC Centre of Excellence for All Sky Astrophysics in Three Dimensions (ASTRO-3D) used data from the now-retired Kepler mission to measure starquakes in the Milky Way's disk.

From this, they have revised the official estimates on the age of the Milky Way's thick disk, which they conclude is around 10 billion years old.

The study which describes their findings – titled "The K2-HERMES Survey: age and metallicity of the thick disc" – recently appeared in the Monthly Notices of the Royal Astronomical Society. The research team was led by Dr. Sanjib Sharma of the Sydney Institute for Astronomy and the ARC Centre of Excellence for All Sky Astrophysics in Three Dimensions (ASTRO-3D) and included members from multiple universities and research institutes. Read the free article.