Torino scale the validity and societal impact of SETI data. The Torino Scale also uses a color code scale: white, green, yellow, orange, red. Each color code has an overall meaning: No object has ever been rated above level 4. The Chicxulub impact, believed by most scientists to be a significant factor in the extinction of the dinosaurs, has been estimated at 100 million (10) megatons, or Torino Scale 10. The impacts which created the Barringer Crater and the Tunguska event in 1908 are both estimated to be in the 3–10 megaton range, corresponding to Torino Scale 8. The 2013 Chelyabinsk meteor
Orange (colour) a symbol of activity. Orange is sometimes used, like red and yellow, as a colour warning of possible danger or calling for caution. A skull against an orange background means a toxic substance or poison. In the colour system devised by the US Department of Homeland Security to measure the threat of terrorist attack, an orange level is second only to a red level. The US Manual on Uniform Traffic Control Devices specifies orange for use in temporary and construction signage. Because of its symbolic meaning as the orange colour of activity, orange is often used as the colour of