Ключевые слова: abstract, alert, area, background, bacteria, bio, biohazard, biologic, biological, biology, caution, chemical, contaminated, danger, dangerous, epidemic, forbidden, hazard, lab, light, milky way, night, night sky, notice, protect, protection, red, research, restricted, risk, safety, science, scientific, security, shiny, sign, signal, sky, space, star, starlight, starry, stars, substance, symbol, toxic, triangle, virus, warn,