Alien hunters should search for artifacts on the moon, study suggests

The famous equation used to search for alien civilizations has now inspired a new formula to hunt for alien artifacts within our solar system.

The quest for these alien artifacts could start with the moon and other cosmic bodies near Earth, a new study finds.

The Drake Equation is used to estimate the number of civilizations in the Milky Way one can detect via their broadcast signals — or, more simply put, the odds of finding intelligent life in our galaxy. First proposed by radio astronomer Frank Drake in 1961, the equation calculates the number of communicating civilizations by analyzing several variables, such as the rate of formation of stars suitable for the development of intelligent life and the number of planets, per stellar system, with an environment suitable for life.
Currently, virtually all SETI (search for extraterrestrial intelligence) experiments scan the skies looking for radio or light signals. However, over the years, some researchers have suggested that another, potentially better way to find evidence of alien life is to not look for broadcasts from afar, but instead to hunt for what are essentially messages in a bottle — a SETA (search for extraterrestrial artifacts) approach.

For example, in 2004, researchers suggested that broadcasting a signal across the cosmos is expensive and inefficient. Instead, the scientists calculated that inscribing messages onto a hunk of matter and launching it at potential extraterrestrial pen pals would require about a trillionth as much energy.

Another concern with conventional SETI is that extraterrestrial civilizations may be long dead by the time astronomers do actually detect signals from them. In contrast, extraterrestrial artifacts could provide a way for us to directly learn about alien civilizations, especially if these artifacts are equipped with artificial intelligence, study author James Benford, a physicist at Microwave Sciences in Lafayette, California.
Alien hunters should search for artifacts on the moon, study suggests