The Sun moves through space primarily by orbiting the center of the Milky Way galaxy at an average speed of approximately 230 km/s (828,000 km/h or about 514,000 mph). This orbit, called a galactic year, takes the Sun about 220 to 250 million Earth years to complete.
Besides this orbital motion, the Sun also moves relative to nearby stars with a peculiar velocity of about 20 km/s (12.2 miles/s). The Solar System as a whole moves through the galaxy at roughly this speed on top of the orbital velocity.
In addition, the Milky Way galaxy itself moves through the universe at roughly 550 km/s, so the Sun’s total speed relative to the cosmic microwave background is about 370 km/s.
If interpreting the Sun’s movement as seen from Earth across the sky, the Sun appears to move at an angular speed of about 15 degrees per hour due to Earth's rotation, which corresponds to the Sun’s apparent motion rather than actual spatial velocity.
In sum, the Sun’s actual spatial velocity through the galaxy is about 230 km/s, while apparent movement across the sky is about 15 degrees per hour. References:
- Sun's orbit speed around the galaxy: ~230 km/s (828,000 km/h)
- Solar System's peculiar velocity relative to local stars: ~20 km/s
- Milky Way's velocity through the universe: ~550 km/s
- Sun’s apparent movement in the sky: ~15 degrees per hour
