The Sun Has Made Only About 20 Trips Around the Milky Way
The Sun takes about 230 million years to orbit the Milky Way, so in its roughly 4.6-billion-year life it has made only about 20 trips.
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The Sun is not sitting still in the Milky Way. Our entire solar system travels around the center of the galaxy, carrying Earth and the other planets along with it. One complete galactic orbit takes roughly 230 million Earth years. NASA gives an average speed of about 720,000 kilometers per hour for this motion. Since the Sun formed about 4.6 billion years ago, that works out to roughly 20 completed trips around the Milky Way. The exact count is not a precise birthday counter because the orbital period is an estimate and the Sun follows a complicated path through the galaxy, but the basic scale is striking: an entire human civilization occupies only a tiny fraction of one galactic orbit. The Sun is also not simply circling the central black hole by itself. The motion is governed by the combined gravitational influence of the enormous mass distributed throughout the Milky Way, including stars, gas, and dark matter. The familiar phrase galactic year refers to the approximate time the solar system needs to make one revolution around the galactic center.
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