With a diameter of between 80,000 and 120.000 light years and a thickness of around 7,000 light years, the Milky Way is believed to have a spiral shape. The Sun and its planets lie between 26,000 and 28,000 light years from the galactic core, completing an orbit around it every 200 to 250 billion years. The solar system's orbit sometimes places it above or below the galaxy's equatorial plane, which affects the amount of radiation it receives from the core's magnetic fields.
Sophisticated new methods for observing the Milky Way's core reveal a tangle of disordered filaments, the nature of which remains under debate. This field, invisible behind clouds of dust and gas, is more powerful than any other in the galaxy and exerts a force strong enough to deform the shape of the solar system in its orbit around the galactic core.
The solar wind, a constant stream of radiation emitted from the sun, forms the heliosphere, a giant bubble holding all the bodies of the solar system. Recent astronomical research focusing on the interaction between the heliosphere and galactic magnetic fields suggests that although the heliosphere diverts the magnetic medium around it, these fields force the solar system into a bullet shape and force it to tilt relative to the galactic plane.
Studies of the effect of the Milky Way's magnetic fields on the solar system raise speculation about implications for life on Earth. One theory notes that periods in which the solar system's orbit takes it either above or below the galactic plane appear to coincide with episodes of mass extinction on Earth. Others point out that the complex interactions between galactic magnetic fields and the heliosphere may make Earth vulnerable to shifts in the Milky Way's magnetic fields over time.