Questionnaire Survey on Luminous Phenomena Associated with the 1995 Hyogo-ken Nanbu (Kobe) Earthquake

Abstract

Many types of luminous phenomena were observed at the 1995 Hyogo-ken Nanbu earthquake (Kobe earthquake) of January 17, 1995. A questionnaire survey was done regarding luminous phenomena in order to determine 1) spatial distribution of eyewitnesses of luminous phenomena; 2) origin-times and duration-times of the phenomena; 3) properties of lights, such as color, shape, and brightness.
Out of 798 people surveyed, 31 answerers (3.9% of the total) reported that they had observed luminous phenomena. Characteristics of the phenomena may be described as follows; a) More than 50% of the eyewitnesses were within 10km of the epicenter of the main shock. b) Almost all observations of the phenomena occurred simultaneously, or at a maximum of 2-3 minutes from the arrival of the seismic wave to the eyewitnesses' location. c) The duration-time of the phenomena was less than 30 seconds. d) The gross form of luminescence was a belt of light or curtain shape. e) The colors of luminescence were white, blue, and orange, while blue-white was predominant.