Initial scans for alien technology aboard the mysterious interstellar object 'Oumuamua have found no evidence that it is anything other than a lump of space rock, scientists have announced. The first observations, made by the Breakthrough Listen project, swept the object for radio signals across four bands of the radio spectrum, but detected no transmissions.
The cigar-shaped body, which is about 400 metres long, was spotted hurtling through the solar system in October. Its unusual shape led astronomers to consider the possibility that it might be an alien spacecraft, despite initial suspicions that it was an interstellar asteroid. The object is tumbling through space, which suggests any aerodynamic advantage from its elongated form is minimal.
Using the Green Bank telescope in West Virginia, researchers eavesdropped on 'Oumuamua while it was twice as far from Earth as the sun. The telescope is so sensitive it could have picked up transmissions as weak as those from a mobile phone. However, a review of all four observed frequency bands, spanning 1 to 12 GHz, came up blank.
Avi Loeb, professor of astronomy at Harvard University and an adviser to the Breakthrough Listen project, described the search as a fishing expedition. "We are most likely not to find anything, but it is worth checking steadily our fishing hooks. We will keep searching for artificial signals from 'Oumuamua or any other interstellar object that will be discovered in the future," he said.
Andrew Siemion, director of Berkeley Seti Research Center, said no continuous emission had been detected. "We're now digging into some of the intermittent candidates, and trying some new machine learning-based techniques," he noted. The project has released the data for public analysis, with further observations expected on Friday or Saturday as 'Oumuamua continues its rapid journey out of the solar system.
