Gravitational Wave Pins and Buttons

This waveform (GW150914) is that of the first observation of gravitational waves on 2015-09-14. It was also the first observation of a binary black hole merger and demonstrates the existence of binary stellar-mass black hole systems.

Gravitational Waves (halftone).

Gravitational Waves (light design).

A black hole is an object so compact -- usually a collapsed star -- that nothing can escape its gravitational pull. Not even light. In this image, we can see a black hole, but only because it is surrounded by a superheated disc of material, an accretion disc.

Without the Universe, there would be no us. Physics is the scientific discipline that aims to understand the Universe.

The Doppler Effect or Doppler shift is the change in frequency of a wave in relation to an observer who is moving relative to the wave source.

The Doppler Effect or Doppler shift is the change in frequency of a wave in relation to an observer who is moving relative to the wave source.