Researchers from Switzerland have presented a new way to define the properties of life. They were able to do this from a long distance and at a speed of 70 km/h.
Scientists led by the University of Bern and the National Center for Research Competence (NCCR) presented the PlanetS technology. They determine the key molecular property of all living organisms from a helicopter flying several kilometers above the ground. Measurement technology can also open up possibilities for remote sensing.
The researchers explained that most of the molecules in the cells of living organisms are chiral. However, they are usually found in “left-sided” or “right-sided” variants – they are homochiral. But this molecular feature is a characteristic property of life, the so-called biosignature.
An international team of researchers was able to detect this signature from a distance of 2 km and at a speed of 70 km / h. “The main achievement of the project is that these measurements were carried out on a moving, vibrating platform, but we still found these biosignatures in a matter of seconds,” the scientists noted.
“When light reflects off biological matter, some of the electromagnetic waves of light will spiral clockwise or counterclockwise. This phenomenon is called circular polarization and is caused by the homochirality of biological matter. Such spirals of light do not form in abiotic inanimate nature, ”explained the first author of the study, Lucas Patti.
Measuring this circular polarization is challenging. The signal is quite weak and usually less than one percent of the reflected light. To measure it, the team developed a special device called a spectropolarimeter. It consists of a camera equipped with special lenses and receivers capable of separating circular polarization from the rest of the light.