20 Euro Austria 2022 - Black hole

20 Euro Austria 2022 - Black Hole

Description:

A unique piece for a unique phenomenon. Concave on one side and convex on the other, The Black Hole illustrates the funnel-like shape of those regions of space-time where gravity is so strong that nothing can escape. One way to think of a black hole is as a vortex that attracts everything in its immediate vicinity. Once beyond the point of no return - called the "event horizon" - the "singularity" waits at the center.

Although they store vast quantities of energy, black holes do not emit light. For this reason, the first photograph of a black hole was not published until 2019 and, even then, only as an indirect image of the shadow it casts. No wonder so much remains unclear about black holes. Among the most complex objects possible in our universe or any other, they are not only an experimental challenge but also raise a multitude of fundamental questions about space and time.

COIN MOTIF

The vortex phenomenon of black holes is illustrated on the reverse of the coin in the form of a funnel decorated with a spiral printed in full color. On the obverse of the coin, a cone rises from the flat silver surface, representing the curvature of space-time. 'Cygnus X-1', the name of the first black hole so named, is written on the right below '15 M☉', the solar mass of this black hole. In German, "Event horizon" marks the boundary between the observable and the unobservable in space-time, while "Singularity" indicates the location of the maximum curvature of space-time.

Composition: Silver 925/1000

Diameter: 34 mm

Weight: 22.42 g

Circulation: 30,000