The Sun completes one orbit around the center of the Milky Way galaxy approximately every 225 to 250 million years. This means that since its formation about 4.6 billion years ago, the Sun has completed about 20 to 21 orbits around the galactic center. However, it is important to note that the accuracy of these numbers can vary depending on the estimates and astronomical models used.

Just that?

Indeed, the velocity of the Solar System relative to the center of the Milky Way is significant, but when compared to hypervelocity stars, it seems modest. And thinking about the timescale involved in galactic orbits really makes us realize how vast and ancient the cosmos is.

It is true that the number of orbits of the Sun around the galactic center can vary depending on the astronomical models used. In addition, the complexity of the orbital dynamics within the galaxy can also affect these calculations. Still, it is fascinating to contemplate the long journey that the Sun has already made in its orbit around the supermassive black hole Sagittarius A* at the center of the Milky Way.

The crux of the matter

The displacement of the Solar System relative to the galactic center is actually an important aspect to consider when calculating how many times the Sun has orbited the Milky Way. Radial migration is a complex phenomenon that involves gravitational interactions between the Solar System and other celestial bodies over time.

Understanding the speed and nature of this migration better is essential to more accurately estimating the number of complete orbits of the Sun around the galaxy. And, as you mentioned, the Solar System may still continue to gradually move away from the galactic center in the future.

This aspect adds a layer of complexity to the calculation, but also highlights scientists' constant quest to better understand the movements and evolution of our star system within the Milky Way.