Impact Effects

Thermal Radiation:

What does this mean?

Time for maximum radiation: 398 seconds after impact

Your position is inside the fireball.

The fireball appears 819 times larger than the sun

Thermal Exposure: 1.65 x 10¹² Joules/m²

Duration of Irradiation: 25800 seconds

Radiant flux (relative to the sun): 63900

Effects of Thermal Radiation:

Clothing ignites

Much of the body suffers third degree burns

Newspaper ignites

Plywood flames

Deciduous trees ignite

Grass ignites

Seismic Effects:

What does this mean?


The major seismic shaking will arrive at approximately 1000 seconds.

Richter Scale Magnitude: 14.2 (This is greater than any earthquake in recorded history)

Mercalli Scale Intensity at a distance of 5000 km:

IX. General panic. Damage considerable in specially designed structures; well-designed frame structures thrown out of plumb. Damage great in substantial buildings, with partial collapse. Buildings shifted off foundations. Serious damage to reservoirs. Underground pipes broken. Conspicuous cracks in ground. In alluviated areas sand and mud ejected, earthquake fountains, sand craters.

X. Most masonry and frame structures destroyed with their foundations. Some well-built wooden structures and bridges destroyed. Serious damage to dams, dikes, embankments. Large landslides. Water thrown on banks of canals, rivers, lakes, etc. Sand and mud shifted horizontally on beaches and flat land. Rails bent slightly.

Ejecta:

What does this mean?


The ejecta will arrive approximately 1570 seconds after the impact.

Your position is in the region which collapses into the final crater.

Your position is beneath the continuous ejecta deposit.

Average Ejecta Thickness: 8160 m = 26800 ft

Air Blast:

What does this mean?


The air blast will arrive at approximately 15200 seconds.

Peak Overpressure: 2.11e+08 Pa = 2110 bars = 30000 psi

Max wind velocity: 11700 m/s = 26200 mph

Sound Intensity: 166 dB (Dangerously Loud)

Damage Description:

Multistory wall-bearing buildings will collapse.

Wood frame buildings will almost completely collapse.

Multistory steel-framed office-type buildings will suffer extreme frame distortion, incipient collapse.

Highway truss bridges will collapse.

Highway girder bridges will collapse.

Glass windows will shatter.

Cars and trucks will be largely displaced and grossly distorted and will require rebuilding before use.

Up to 90 percent of trees blown down; remainder stripped of branches and leaves.

Click here for a pdf document that details the observations, assumptions, and equations upon which this program is based. It describes our approach to quantifying the important impact processes that might affect the people, buildings, and landscape in the vicinity of an impact event and discusses the uncertainty in our predictions. The processes included are: atmospheric entry, impact crater formation, fireball expansion and thermal radiation, ejecta deposition, seismic shaking, and the propagation of the atmospheric blast wave.