By Ken Croswell
One of Saturn’s rings has revealed properties of its core, hidden deep beneath the planet’s golden atmosphere.
That core isn’t the lump of rock and ice that many scientists had envisioned, the new study finds. Instead, the core is diffuse, pervaded by huge amounts of hydrogen and helium and so spread out that it spans 70,000 kilometers, or about 60 percent of the planet’s diameter, researchers report April 28 at arXiv.org.
The new intel should help planetary scientists better understand not only how giant planets formed in our solar system but also the nature of such worlds orbiting other stars.
To ascertain the structure of Saturn’s core, astronomer Christopher Mankovich and astrophysicist Jim Fuller, both at Caltech, examined the giant planet’s rings. Just as earthquakes help seismologists probe Earth’s interior, oscillations inside Saturn can reveal its internal composition. These oscillations alter Saturn’s gravitational forces, inducing waves in the rings —especially the C ring, which is the nearest of the three main rings to the planet (SN: 1/22/19).