Planetary science: Proto-planetary impact gave lunar region its grooves
Nature
2016년7월21일
The unusual structure of one of the Moon’s largest impact basins may have been created by ejected pieces of an impacting proto-planet, a study published in Nature suggests. New calculations indicate that the object was around 250 kilometres in diameter, larger than previously thought. The findings provide insights into the size of objects in the E-belt of asteroids that bombarded planets and shaped the nearside of the Moon around 4 billion years ago.
Patterning of the lunar region Mare Imbrium, known as the Imbrium Sculpture, is made up of grooves surrounding a 1,250-kilometre-diameter crater. Some of these furrows appear to have been ploughed out by fragments of the body that created the giant crater rather than by material excavated from the impact site, Peter Schultz and David Crawford propose. Assessment of these patterns, informed by numerical and laboratory impact simulations, allow them to estimate the object’s size - almost half the diameter of the proto-planet Vesta.
The authors conclude that the impactor was once part of a population of proto-planets in the E-belt, and that large pieces of the object would have escaped the impact to create further craters throughout the inner Solar System. They infer from the estimated size of the impacting object that a larger mass of material than previously thought seems to have battered the Moon and other planets during the Late Heavy Bombardment between 4.1 and 3.7 billion years ago.
doi: 10.1038/nature18278
리서치 하이라이트
-
8월4일
Environment: Extreme flooding and drought make risk management difficultNature
-
8월3일
Environment: Salt may inhibit lightning in sea stormsNature Communications
-
7월29일
Environment: Costs of amphibian and reptile invasions exceeded US$ 17 billion between 1986 and 2020Scientific Reports
-
7월27일
Environment: Plastic pollution encourages bacterial growth in lakesNature Communications
-
7월27일
Ecology: Using fallow land to grow vanilla increases biodiversityNature Communications
-
7월26일
Palaeontology: Attenborough fossil provides insights into jellyfish familyNature Ecology & Evolution