A recent study indicates that minerals on the surface of Venus could tell scientists whether or not the planet once had a global magnetic field as powerful as the Earth’s. Venus has no magnetic field today, but some models indicate that the planet could have supported a global magnetic field up until a billion years ago.

Earth’s global magnetic field is thought to be tied to properties of the planet’s fluid, metallic core. If conditions were similar on Venus at some point in the planet’s past, evidence of an ancient magnetic field could be found in magnetized rocks at Venus’ surface. Magnetized rocks have already been identified on the Moon, Mars, and Mercury. However, the surface of Venus is so hot that many scientists believe ancient magnetization in rocks would not be stable enough to survive on the surface today.

The new study shows that common minerals (such as magnetite) could be stable on Venus for billions of years, even when exposed to current Venus surface temperatures. In fact, the team behind the research believes that there could be enough magnetized material in the Venusian crust for it to be detected by low altitude orbiters or aerial missions to the planet’s atmosphere.