Gamma rays are the most energetic light in the Universe. But one part of them, the medium-energy range, long remained invisible: instruments couldn't catch them, leaving a gaping hole in the sky. Scientists call it the "MeV gap," named after the unit of energy these rays carry.
The new camera works like a three-layer detective. The first layer catches the ray, the second tracks where it bounced, and the third fills in the picture. Together, they determine where the gamma photon came from with precision down to two millimeters: that's like hitting a coin with a needle from across the room.
The camera has already been tested in the lab: it clearly sees gamma-ray sources. Soon it will be sent into space, and then the window into invisible light will finally open.
A gamma photon with an energy of 1 MeV carries a million times more energy than a photon of visible light, but the eye can't see it: you need a clever detector.
In the novel "Solaris," people investigate the unknown radiation of an ocean — the new camera will also help us see what is hidden from the eye.