Solar system's movements causes cyclic mass extinctions.
Just as it takes one day for the earth to spin on it's axis, 28 days for the moon to travel around the Earth, one year for the Earth to travel around our Sun, it takes 64 million years for our solar system to travel around the galaxy.
Earth's biodiversity dips every 62 million years.
Astrobiologists have put the two facts together leading to theories that our solar sytem's merry-go-round path though the disc of the galaxy is the cause of the regular cyclical mass extinctions that the fossil records show.
One theory has it that our Solar Systems experiences higher exposure to life harming extragalactic cosmic ray flux as it passes through the most northerly aspect of our galactic plane.
Most of Earth's biggest extinctions occurred when the solar system was at its most northerly point in its cycle, which stretches about 230 light years above the galactic plane. Medvedev says that more cosmic rays enter the Earth's atmosphere at that point, killing off species.If this theory holds out it may be all the more reason why we should not put more cosmic ray trapping carbon dioxide into our atmosphere.
He says the effect is similar to the compression of the solar system's protective solar wind when it passes through a giant hydrogen cloud. The Milky Way's stars produce a wind of charged particles whose magnetic fields deflect incoming cosmic rays from beyond the galaxy.
But the entire Milky Way is moving due north at 200 kilometres per second towards a giant grouping of galaxies called the Virgo Cluster. This movement compresses the galactic wind on the galaxy's north side, allowing in higher levels of potentially life-harming extragalactic cosmic rays, says Medvedev.
"When the Sun is moving up through the galactic plane, the cosmic ray flux is increasing, and when it goes down through the plane, it's decreasing," he told the conference. He said the periods of high extragalactic cosmic ray influxes match observed lows in biodiversity so well that the alignment has just a one in 10 million chance of being a coincidence.
Global Warning Climate Change Environment Science CO2 Extinction, Biodiversity, Solar+System, Space, Milky+Way Earth