Our moon, named Luna, is an easily observable object in the sky appearing during the day and night. The popular hypothesis of why we have a moon is that about 4.5 billion years ago it is believed the planet Theia collided with the young Earth. This collision sent rock and debris into orbit. Over time , 10 - 100 million years, gravitational forces pulled this rock and debris together until they were compressed into our moon. Only twelve people have walked on our moon and we now have plans to return to the moon in April 2026 via the Artemis program.