Digital holograms — 3D images recorded using lasers — may be our best bet for finding alien life, scientists say.

No probe since NASA’s Viking program in the late 1970s has explicitly searched for extraterrestrial life. Rather, the focus has been on finding water.

Lit wit laser

In digital holographic microscopy, an object is illuminated with a laser and the light that bounces off the object and back to a detector is measured. This scattered light contains information about the intensity of the scattered light and about its phase — a property that can be used to tell how far the light travelled.

With the two types of information, a computer can reconstruct a 3D image of the object — one that can show motion through all three dimensions.