There are over 100 billion stars in our galaxy. Yet the search for extraterrestrial intelligence has come up empty while looking for alien signals. Some “great filter” likely exists, preventing life from developing or progressing to colonize the galaxy. Perhaps this filter is the unusually high intelligence that humans possess.
Elon Musk recently unveiled his plan to colonize Mars. If he’s successful, a one million person, self-sustaining colony on Mars could be achieved within 50 to 100 years.