Astronauts and cosmonauts have observed their religions while in space, both publicly and privately. Muslims aboard the International Space Station have struggled with fulfilling their religious duties including kneeling and facing Mecca to pray in microgravity while traveling at thousands of miles per hour. As more people travel into space the practical concerns of practicing Earth-bound religions will become more evident. How will people living on other worlds have to adjust where the days and years are different? How will the religious faiths of future space settlers change as more and more people take up a permanent presence on places like the Moon and Mars?