By Mike Wall, Space.com Senior Writer | May 23, 2017 07:00am ET
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The structure of a planet, a planet with a disk and a synestia, all of the same mass. Credit: Simon Lock and Sarah Stewart
Earth probably became a "synestia" for a brief period about 4.5 billion years ago, according to a new study.
That's the term for a newly proposed cosmic object: a huge, hot, donut- shaped mass of vaporized rock that results from the collision of two planet- size bodies.