Year 2154: Humanity establishes its first lunar colony.
We finally get around to colonizing our closest celestial neighbor. The moon, with its vast resource deposits and low-gravity environment, is the obvious choice for our first offworld colony.
Year 2200: Mars becomes a popular tourist destination.
We start sending rich folks to Mars for a taste of the high-life. The red planet's low gravity and lack of atmosphere make for a fun vacation spot, but don't expect any actual amenities or infrastructure.
Year 2250: Interstellar travel becomes possible, but expensive.
We figure out how to make interstellar travel feasible, but it's still a luxury only the ultra-rich can afford. The first few pioneers to make the journey back to Earth are greeted as heroes.