* No central "sun": Unlike our solar system, the Milky Way doesn't have a single central star that everything revolves around. The stars, planets, and gas clouds within the galaxy all move in their own orbits around the galaxy's center.
* Different orbital periods: Stars and other objects in the Milky Way have different orbital periods, meaning the time it takes them to complete one full orbit around the galaxy's center. These periods can range from millions to billions of years.
What we CAN say about time in the Milky Way:
* Galactic year: We can talk about a "galactic year", which is the time it takes the Sun to complete one orbit around the Milky Way's center. This is estimated to be around 225 to 250 million Earth years.
* Stellar rotations: Individual stars within the galaxy also have their own rotation periods, which can vary depending on their size and composition.
So, while we can't talk about a "day" in the Milky Way in the same way we do on Earth, we can talk about the time it takes objects to complete orbits or rotations within the galaxy.
