What role did aluminum-26 play in early planetary magma oceans?

In the early Solar System, the radioactive decay of aluminum-26 provided the heat necessary to melt small planetesimals and form initial magma oceans. As planets grew larger over time, heat from giant impacts took over this role. These molten surface layers were integral to planetary accretion, differentiation, and the early degassing of atmospheres and hydrospheres.

What we know

• Magma oceans are vast fields of surface magma that occur when a planet or natural satellite is completely or partly molten during periods of accretion. [2, 4]
• In the early Solar System, small planetesimals were melted by the heat provided by the radioactive decay of aluminium-26. [2]
• As planets grew larger, energy for creating magma oceans was supplied from giant impacts with other planetary bodies. [2]
• Magma oceans facilitate planetary formation processes such as core formation through metal segregation, as well as the degassing of atmospheres and hydrospheres. [2]

Where to go next

• what caused itHow do giant impacts form magma oceans?
• the bigger pictureWhat is planetary differentiation?
• how we knowWhat evidence supports magma oceans on Earth and the Moon?
• how it workedHow does metal segregation form a planetary core?
• compared withDo exoplanets also have magma oceans?
• an unexpected connectionHow does radioactive decay help build planetary cores?Heat from the radioactive decay of isotopes like aluminum-26 melts planetesimals into magma oceans, which subsequently mediates the sinking of metals to form planetary cores.

Sources

• [1]magma ocean (Wikidata Q12034896) · CC0 1.0
• [2]Magma ocean · CC BY-SA 4.0
• [3]Planetary differentiation · CC BY-SA 4.0
• [4]Planetary oceanography · CC BY-SA 4.0
• [5]Mid-ocean ridge · CC BY-SA 4.0