Hurtling at 514,000 mph, the solar system bobs up and down through the galaxy like a carousel horse. The last time Earth was in this exact spot, dinosaurs had just begun to evolve.
The Sun and its planets are in a massive orbit around the supermassive black hole at the center of the Milky Way, located about 26,000 light-years away. It takes roughly 225 to 250 million years to complete one full revolution.
The solar system does not travel completely flat along the galactic disk. The plane in which the planets orbit the Sun is tilted at a 60-degree angle relative to the plane of the Milky Way. As the Sun circles the galactic center, it crosses the midplane every 30 million years or so, oscillating vertically in a path that resembles a wave.
Currently, the overall direction of the Sun's trajectory—known as the solar apex—points roughly toward the star Vega in the constellation of Lyra. As the Sun moves toward this apex, it drags the planets along with it while plowing through the interstellar medium.
This forward motion creates a dynamic interaction with the space around it. The solar wind, a constant stream of charged particles emitted by the Sun, blows outward and forms a protective magnetic bubble called the heliosphere. When this outward pressure meets the gas and dust of interstellar space, it creates a bow wave ahead of the solar system, similar to the water parting at the front of a moving ship. This boundary shields the planets from a significant portion of high-energy cosmic rays as the entire system makes its quarter-billion-year journey around the galaxy.