Formation of Lunar Basins from Impacts of Leftover Planetesimals - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles The Astrophysical journal letters Year : 2022

Formation of Lunar Basins from Impacts of Leftover Planetesimals

David Nesvorný
  • Function : Author
Fernando V. Roig
  • Function : Author
David Vokrouhlický
  • Function : Author
William F. Bottke
  • Function : Author
Simone Marchi
  • Function : Author
Rogerio Deienno
  • Function : Author


The Moon holds important clues to the early evolution of the solar system. Some 50 impact basins (crater diameter D > 300 km) have been recognized on the lunar surface, implying that the early impact flux was much higher than it is now. The basin-forming impactors were suspected to be asteroids released from an inner extension of the main belt (1.8-2.0 au). Here we show that most impactors were instead rocky planetesimals left behind at ~0.5-1.5 au after the terrestrial planet accretion. The number of basins expected from impacts of leftover planetesimals largely exceeds the number of known lunar basins, suggesting that the first ~200 Myr of impacts are not recorded on the lunar surface. The Imbrium basin formation (age ≃3.92 Gyr; impactor diameter d ≳ 100 km) occurs with a 15%-35% probability in our model. Imbrium must have formed unusually late to have only two smaller basins (Orientale and Schrödinger) forming afterwards. The model predicts ≃20 d > 10 km impacts on the Earth 2.5-3.5 Gyr ago (Ga), which is comparable to the number of known spherule beds in the late Archean.
Fichier principal
Vignette du fichier
Nesvorný_2022_ApJL_941_L9.pdf (1.18 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive

Dates and versions

insu-04004079 , version 1 (24-02-2023)


Attribution - CC BY 4.0



David Nesvorný, Fernando V. Roig, David Vokrouhlický, William F. Bottke, Simone Marchi, et al.. Formation of Lunar Basins from Impacts of Leftover Planetesimals. The Astrophysical journal letters, 2022, 941, ⟨10.3847/2041-8213/aca40e⟩. ⟨insu-04004079⟩
2 View
2 Download



Gmail Facebook Twitter LinkedIn More