Did Dark Matter Kill the Dinosaurs?
Dark matter may have been responsible for the comet strike that killed off the dinosaurs 66 million years ago, as well as other mass extinction events and geologic upheavals, according to one scientist.
Although dark matter has never been seen, it is believed to exist based on its gravitational effects in the Universe. Scientists credit the invisible substance with keeping planets, stars and other celestial bodies in place.
This includes what is known as the Galactic disc - the region of the Milky Way Galaxy where our solar system resides. The Earth doesn't just spin around the Sun, but occasionally moves around our Galaxy's disc as well. Biology Professor Michael Rampino from New York University believes that as the Earth passes through the disc's areas of concentrated dark matter, it may have a huge impact on our planet's biology and geology.
According to his report published in the journal Monthly Notices of the Royal Astronomical Society, movement through dark matter changes the orbits of comets and leads to additional heating in the Earth's core, which can cause mass extinction events.
Earth rotates around the disc-shaped Galaxy only once every 250 million years, however, its wavy orbit brings it to the crowded center of the disc every 30 million years, where there theoretically should be more dark matter. Rampino discovered that these periods of time correlate with past comet impacts and mass extinctions. This includes the famous cosmic event that led to mass die-offs of the dinosaurs.
"The history of the Earth is punctuated by large scale extinction events, some of which we struggle to explain. It may be that dark matter - the nature of which is still unclear but which makes up around a quarter of the Universe - holds the answer," Rampino said in a press release. "As well as being important on the largest scales, dark matter may have a direct influence on life on Earth."
For example, because of dark matter, comets that would normally travel at great distances from the Earth instead take unusual paths, causing some of them to collide with the planet. And with each dip into the disc, the dark matter can accumulate within the Earth's core, producing considerable heat. This, in turn, can trigger volcanic eruptions, mountain building, magnetic field reversals and changes in sea level, all of which coincidentally show peaks every 30 million years.
Based on this model of how dark matter interacts with the Earth, it seems that astrophysical phenomena can sometimes have catastrophic and life-altering impacts here on Earth. This research may help scientists better understand the kind of role dark matter plays in the Universe.
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