Intense radiation of light, covering the visible region and extending into the infrared region, has been observed when powder materials are shock compressed in plate-impact experiments. The time duration of the radiation is on the order of 10 ns, and the intensity increases with the shock strength, but intense radiation is still observed in the visible region for very weak shocks. Thermal radiation from the shock-compressed powder cannot explain the observed radiation spectrum. Adiabatic compression of the residual gas in the shock-compressed powder appears to generate high temperatures and intense thermal radiation. (C) 2013 Elsevier B.V. All rights reserved.