ASTRONOMY AND SPACE EXPLORATION

Viewpoint: Yes, the giant impact theory provides a compelling and plausible explanation for the formation of the Moon.

Viewpoint: No, while the giant impact theory is widely regarded as a better explanation for the Moon's formation than previous ones, it still has many problems that must be resolved.

Humanity is perennially involved in a quest for origins, whether our own, that of our universe, or of our own planet. In the case of Earth and its only natural satellite, the Moon, this involves peering back some four and one-half billion years into the past. While the age of the Sun, the solar...