Astronomers have so far been attempting to find alien life by sniffing out their chemical signature.
But researchers say they have found a better way of finding extra-terrestrial beings: through vibrations.
The European team has now created the first tiny motion detector that it claims may someday help find microscopic life forms on distant planets.
Taking advantage of movement, which they call ‘a universal signature of life,’ the sensor aims to identify on a nano-level the tiny motions that all life forms make.
They team began to explore the possibility of searching for life with a sensor attuned to those tiny vibrations in organisms such as bacteria and yeast.
‘The nanomotion detector allows studying life from a new perspective: life is movement,’ said Professor Giovanni Longo at the École Polytechnique Fédérale de Lausanne.
‘This means that the nanomotion detector can detect any small movement of living systems and deliver a complementary point of view in the search for life.’
HOW DOES THE SENSOR WORK?
The sensor uses a nano-sized cantilever to detect motion.
A cantilever is essentially a beam that is anchored only at one end, with the other end bearing a load.
It is most often used with bridges and buildings, but in the sensor it is used on the micrometre scale, and it can hold around 500 bacteria.
The idea comes from the technology behind an existing microscope, the atomic force microscope, which uses a cantilever to produce pictures of the very atoms on a surface.
The cantilever scans the surface like the needle of a record player and its up-and-down movement is read by a laser to produce an image.
The motion sensor works the same way, but here the sample is attached on the cantilever itself. For example, a bacterium attaches to the cantilever.
If the bacterium is alive, it will inevitably move in some way. That motion also moves the much smaller and sensitive cantilever and it is captured by the readout laser as series of vibrations.
The signal is taken as a sign of life.