Our Solar-System’s Milky Way Orbit –“A Danger-Fraught 226-Million-Year Three-Dimensional Ballet”

Milky way Center


Our Solar System’s orbit through the Milky Way has only happened 20.4 times since the Sun itself formed 4.6 billion years ago. It’s estimated that the Sun will continue fusing hydrogen for another 7 billion years. In other words, it only has another 31 orbits it can make before it runs out of fuel. Researchers at Cardiff University suggested that there is a “genocidal countdown” built into the motion of our solar system –that our system’s orbit through the Milky Way encounters regular speedbumps – and by “speedbumps”, meaning “potentially extinction-causing asteroids.”

Our orbit through the Milky Way is not a perfect circle or an ellipse, since the galaxy itself is a landscape of undulating concentrations of mass and complex gravitational fields observes Columbia University astrophysicist Caleb Scharf in The Copernicus Complex. Scharf points out that “none of the components of the galaxy are stationary; they, too, are orbiting and drifting in a three-dimensional ballet. The result is that our solar system, like billions of others, must inevitably encounter patches of interstellar space containing the thicker molecular gases and microscopic dust grains of nebulae. It takes tens of thousands to hundreds of thousands of years to pass through one of these regions.”

“Milky Way Orbit 19” –Extinction by Spiral-Arm Apocalypse

In 1999, astronomers focusing on a star at the center of the Milky Way, measured precisely how long it takes the sun to complete one orbit (a galactic year) of our home galaxy: 226 million years. The last time the sun was at that exact spot of its galactic orbit, dinosaurs ruled the Earth. The Solar System is thought to have completed about 20–25 orbits during its lifetime or 0.0008 orbit since the origin of humans. When the last red embers of our Sun die out billions of years from now, we will have completed approximately 60 orbits of our home galaxy.

The journey through dangerous patches of interstellar space may happen only once every few hundred million years,” observes Scharf, “but if modern human civilization had kicked off during such an episode, we would have barely seen more than the nearest stars— certainly not the rest of our galaxy or the cosmos beyond. But could our planetary circumstances have been that different and still produced us? Would more changeable orbits in a planetary system, or bad weather, or passage through interstellar clouds, also thwart the emergence of life in some way?

Phenomena such as these, Scharf concludes, “could be bad news, causing hostile surface environments on a planet. So it’s a possibility that the planetary requirements for forming sentient life like us will necessarily always present the senses and minds of such creatures with a specific cosmic tableau, a common window onto the universe.”

Mystery of the Milky Way’s Spiral Arms –“Dark Matter May Be the Clue”

If future research confirms a Milky Way galaxy-biodiversity link, it would force scientists to broaden their ideas about what can influence life on Earth. “Maybe it’s not just the climate and the tectonic events on Earth,” says University of Kansas paleontologist Bruce Lieberman. “Maybe we have to start thinking more about the extraterrestrial environment as well.”

The surge in cosmic-ray exposure could have both a direct and indirect effect on Earth’s organisms, said Lieberman. The radiation could lead to higher rates of genetic mutations in organisms or interfere with their ability to repair DNA damage, potentially leading to diseases like cancer.

The Daily Galaxy–Great Discoveries Channel, Jake Burba, via The Copernicus Complex and Newscientist.com

Image credit: An international team of astronomers discovered that the Milky Way’s disc of stars becomes increasingly ‘warped’ and twisted the further away the stars are from the galaxy’s center. “We usually think of spiral galaxies as being quite flat, like Andromeda which you can easily see through a telescope,” says Professor Richard de Grijs, an astronomer from Australia’s Macquarie University.