The authors then compared the probes to "dandelion seeds" (Representational Image)
Pentagon officials said in a draft document that recent UFO sightings could be alien space probes sent to Earth from a giant 'mothership'.
A draft research report was released on March 7 and it focuses on the physical constraints of unidentified aerial phenomena. The draft research is authored by Sean Kirkpatrick, the director of the Pentagon's All-Domain Anomaly Resolution Office (AARO) and Avi Loeb, chairman of Harvard University's astronomy department.
Head of the Pentagon's All-domain Anomaly Resolution Office (AARO), Sean Kirkpatrick claimed in a new academic paper that the objects, which appear to defy all physics, could be 'probes' from an extra-terrestrial 'parent craft', reported Telegraph.
Mr Loeb in the draft paper said that the interstellar objects such as the cigar-shaped "Oumuamua" that scientists spotted flying through the galaxy in 2017 "could potentially be a parent craft that releases many small probes during its close passage to Earth."
The authors then compared the probes to "dandelion seeds" that could be separated from the parent craft by the sun's gravitational force. The authors said that these probes could use starlight to charge their batteries and Earth's water as fuel.
"Habitable planets would be particularly appealing to extra-terrestrial trans-medium probes, capable of moving between space, air and water," the authors wrote in the paper.
"From a large distance, Venus, Earth or Mars would be equally attractive for probes. But upon closer inspection, Earth would show spectral signatures of liquid water and vegetation."
The research paper comes after a month of scrutiny over unidentified flying objects over the US, reported Fox News.