A Violent Splash of Magma That May Have Made the Moon
https://www.nytimes.com/2019/05/01/science/moon-earth-collision.html
Source: By Robin George Andrews, The New York Times.
Excerpt: ...A study [https://www.nature.com/articles/s41561-019-0354-2] published on Monday in Nature Geoscience suggests that the moon was forged from the fires of an ocean of magma sloshing over baby Earth’s surface. If correct, this model may solve a longstanding paradox. Lunar meteorites and samples collected during the Apollo missions show that the moon and Earth have remarkably similar geochemical fingerprints. Scientists suspect that this was likely the result of a giant impactor the size of Mars, known as Theia, that slammed into a young Earth and sent into orbit a spiral of material that coalesced into the moon. Countless computer simulations show that this is possible, but there’s a problem. Such an impact on a relatively solid Earth would have created a moon made mostly out of Theia, not Earth (at least in simulations resulting in the Earth-moon system we observe today, complete with our 24-hour days). ...The new research, led by Natsuki Hosono of the Japan Agency for Marine-Earth Science and Technology, adds what may be the recipe’s missing ingredient. During Earth’s earliest days, it was covered by a sheet of molten silicate rock. Dr. Hosono’s team wondered what would have happened if Theia had crashed into Earth at that time, rather than during a later, cooler, more solid phase....
Source: By Robin George Andrews, The New York Times.
Excerpt: ...A study [https://www.nature.com/articles/s41561-019-0354-2] published on Monday in Nature Geoscience suggests that the moon was forged from the fires of an ocean of magma sloshing over baby Earth’s surface. If correct, this model may solve a longstanding paradox. Lunar meteorites and samples collected during the Apollo missions show that the moon and Earth have remarkably similar geochemical fingerprints. Scientists suspect that this was likely the result of a giant impactor the size of Mars, known as Theia, that slammed into a young Earth and sent into orbit a spiral of material that coalesced into the moon. Countless computer simulations show that this is possible, but there’s a problem. Such an impact on a relatively solid Earth would have created a moon made mostly out of Theia, not Earth (at least in simulations resulting in the Earth-moon system we observe today, complete with our 24-hour days). ...The new research, led by Natsuki Hosono of the Japan Agency for Marine-Earth Science and Technology, adds what may be the recipe’s missing ingredient. During Earth’s earliest days, it was covered by a sheet of molten silicate rock. Dr. Hosono’s team wondered what would have happened if Theia had crashed into Earth at that time, rather than during a later, cooler, more solid phase....