Professor Tomonori Totani from the University of Tokyo suggests that cosmic dust, particularly 1-micrometer grains, could carry evidence of extraterrestrial life to Earth, estimating that around 100,000 such grains may land on our planet each year. In the aftermath of significant cosmic collisions, material from impacted planets can be ejected into space, potentially containing microbial fossils. This material may preserve signs of life, offering a reliable method of detection, unlike the searches focused on communication or atmospheric signatures that may have alternative explanations.
The concept revolves around asteroid impacts scattering planetary material into space, which may include recently deceased or fossilized microorganisms. Smaller particles could escape their solar systems, traveling vast distances and eventually reaching Earth. Although factors such as heat and radiation can destroy small objects in space, Totani’s calculations support the idea that a significant amount of cosmic dust reaches our planet annually.
Grains residing in environments like Antarctic ice or seafloor sediments may remain preserved, but distinguishing extrasolar material from that of our solar system poses challenges. Existing missions employing aerogels to capture space dust may facilitate this exploration. Totani urges researchers across various fields to consider this novel approach to the search for extraterrestrial life.
