Astronomers say that they have discovered the first example of a long-sought cosmic oddity: a bloated, dying star with a surprise in its core — an ultra-dense neutron star.
Such entities, known as Thorne-Zytkow objects, are theoretically possible but would alter scientists' understanding of how stars can be powered. Since Thorne-Zytkow objects were first proposed in 1975, researchers have occasionally offered up candidates, but none have been confirmed.
The latest work, reported on 6 January at a meeting of the American Astronomical Society outside Washington DC, focuses on a red supergiant star in the Small Magellanic Cloud, a neighboring galaxy to the Milky Way. The star is enriched in lithium, rubidium and molybdenum. Elevated amounts of these elements are thought to arise as by-products of Thorne-Zytkow objects, which have to burn through unusual nuclear fusion pathways.