Earth Biodiversity Pattern May Trace Back to Bobbing Solar System Path

As the sun orbits around the center of the Milky Way, it bobs up and down relative to the plane of the galactic disk. Every 64 million years, our solar system pops above the "northern" edge of the disk, exposing Earth to a barrage of dangerous cosmic rays that may be affecting biodiversity on the planet. (Image credit: Mikhail Medvedev, courtesy of Dimitra Atri)

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So what's in store for Earth in the near future? The solar system is on the upswing now, bobbing toward the northern edge of the galactic disk. But big increases in cosmic-ray exposure are probably still about 10 million years off, researchers have said.

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Mike Wall
Senior Space Writer

Michael Wall is a Senior Space Writer with and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.