Can astronauts go outside the Milky Way Galaxy?

Answer 1

Theoretically, yes. However, no human has ever been outside the Milky Way Galaxy and it's not clear that we ever will, either. Most space exploration is done by robots. The Milky Way Galaxy is a collection of millions of stars, including our own solar system. No human has even left our solar system - in fact, humans have not visited any celestial object in the solar system other than the Earth or the Moon. So humans have not even explored all of our solar system, let alone all of the Milky Way Galaxy, let alone anything outside of that.

Further more, only a single robot has ever made it beyond the reaches of our galaxy; dubbed Voyager 1, it has travelled at speeds upwards of 35,000 mps for 25-35 years to reach it's destination.

Below is a pull from Google on it.

1. Voyager 1 is a 722-kilogram (1,592 lb) space probe launched by NASA on September 5, 1977, to study the outer Solar System. Operating for 37 years, 5 months and 4 days as of February 9, 2015, the spacecraft communicates with the Deep SpaceNetwork to receive routine commands and return data.