Bracewell probe

It was proposed by Ronald N. Bracewell in a 1960 paper, as an alternative to interstellar radio communication between widely separated civilizations.

It would seek out technological civilizations—or alternatively, monitor worlds where there is a likelihood of technological civilizations arising—and communicate over "short" distances (compared to the interstellar distances between inhabited worlds) once it discovered a civilization that meets its contact criteria.

It would make its presence known, carry out a dialogue with the contacted culture, and presumably communicate the results of its encounter to its place of origin.

[dubious – discuss][1][2] The near-Earth object 1991 VG was initially suggested as a candidate for a Bracewell probe due to its unusual characteristics.

[3] In more recent years, however, additional discoveries have accounted for the characteristics of 1991 VG, and it is no longer regarded as anomalous.