From the birth of a star to its dramatic finale, The Beauty of the Universe series presents the most spectacular phenomena in the universe in the most spectacular way possible on a coin. Each coin has a different ingenious shape that illustrates its respective astronomical phenomenon to stunning effect. Waves, sweeps and bends recreate the energy and drama of the cosmos. Not just full of dynamic and exciting events, the universe is both infinitely diverse and infinitely beautiful.

Einstein Ring

The man synonymous with the term ‘genius’ was not wrong about many things, but he was wrong about this, as the first Einstein ring was discovered in 1979, some 24 years after the iconic scientist’s death, 70 years ago this year. The second coin in The Beauty of the Universe series, the Einstein Ring provides remarkable insights into the curvature of space-time and this very special galactic curiosity, making it the perfect gift for astronomy enthusiasts of all ages.

According to Einstein’s general theory of relativity, gravity is only one aspect of the geometry of space-time. When a solid body bends space, light is deflected, making it seem to come from different places, such as the edge of a cluster of galaxies. In reality, the light’s source lies exactly behind it and the galaxy is one and the same, not one of several.

Coin motif

A circular wave curves upwards on the obverse of the coin. Representing an Einstein ring, this is the pictorial multiplication of the light source on the left. Between the light source and the observer, a cluster of galaxies is simplified in the centre, which deflects the light many times due to its gravity. The German for ‘gravitational lens’ refers to its function in this context. The formula Δ∅=4GM/bcÇ, which can be used to calculate the deflection of light, completes the design. The coin’s reverse has the same basic shape as the obverse but features a colour-printed interpretation of an Einstein ring.