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How did radioactive isotopes heat some early asteroids?

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Illustration showing a massive asteroid above a city map with a dinosaur silhouette for scale, highlighting the asteroid's size compared to major urban areas. — Asteroid This rock would take out more than just a *T. rex*.

The heating of early asteroids was driven by the decay of short-lived radioactive isotopes, which served as a primary internal heat source during the early stages of the solar system.1

While the exact process responsible for this heating remains a subject of scientific study, the isotopes aluminum-26 and iron-60 are considered the most likely candidates for providing the thermal energy necessary to melt and aqueously alter these bodies. As these radioactive elements decayed within the parent asteroids, they released energy that facilitated geological activity, such as volcanism, which persisted on some larger bodies for as long as 170 million years.1

In addition to radioactive decay, other factors may have contributed to the internal heating of these early asteroids, including:

Heat generated by electric currents induced by early solar activity.1
The release of gravitational potential energy as the asteroids aggregated and formed.1