Relative Frequencies and Magnitudes of Bolide Explosions and Impact Events

In light of the destructive bolide explosion over Chelyabinsk in Russia earlier this month, I have reviewed the recent history of meteoric events. From A.D. 1908 to 2013, there have been 11 confirmed events with potential explosive equivalencies greater than or equal to 10 kilotons of TNT. These are summarized below and suggest an observed frequency of such incidents that is somewhat higher than previous conservative predictions.

Eight of the observed explosions or impact events occurred over the greater Eurasian expanse. This continental zone includes just over 10.3 percent of the planet’s surface area. Extrapolating from these data yields an estimate of about seven such intermediate incidents per decade, which is not much lower than the number allegedly observed by military satellites. During the 105-year period bracketed by the Tunguska and Chelyabinsk explosions, there were also at least four bolides that exceeded 100kt equivalencies.

1908	Tunguska Event	15 Mt
1930	Curuçá River bolide explosion	5 Mt
1932	Arroyomolinos de León bolide	190 kt
1947	Sikhote-Alin impact	10 kt
1972	Great Daylight Fireball	80 kt
1993	Lugo bolide explosion	10 kt
1994	Marshall Islands Fireball	11 kt
2002	Eastern Mediterranean Event	20 kt
2004	Antarctic bolide explosion	12 kt
2009	Sulawesi bolide explosion	50 kt
2013	Chelyabinsk bolide explosion	500 kt
2016	South Atlantic fireball	13 kt

The Great Daylight Fireball of 1972 was caused by a near-Earth asteroid that passed harmlessly through the atmosphere over North America at least 35 miles above the surface. Estimates of its potential damage vary wildly, but I have selected a number in the upper range. Given the speed and luminosity of the bolide, had it grazed the planet at a more acute angle, I expect that the results would have been spectacular and potentially devastating.

As the Chelyabinsk explosion has proven, these intermediate objects present a very real danger. They are smaller, harder to detect, and much more common than the potential doomsday asteroids we can spot now. And we still lack the infrastructure to stop either of these threats.

Updated to include the South Atlantic fireball of 2016, which exploded several hundred miles southeast of Brazil (http://neo.jpl.nasa.gov/fireballs/).

Right-to-Carry Litigation in Summary

While the police finished murdering each other in southern California, and the President prepared “massive” proposals for the Congress, the case of Piszczatoski v. Maenza [now Drake v. Jerejian, 1/09/14] was argued before the U.S. Court of Appeals for the Third Circuit. With an en banc review of the decision in Moore v. Madigan looking unlikely, a victory in Piszczatoski would deepen the circuit split created by the loss in Kachalsky v. Cacace and thus make the conflicting jurisprudence even more difficult for the U.S. Supreme Court to avoid reviewing. Here is a summary of the major right-to-carry cases for those keeping score.

Kachalsky v. Cacace	New York	Lost on appeal at USCA2.
Moore v. Madigan	Illinois	Won on appeal at USCA7.
Palmer v. D.C.	D.C.	Won at U.S. District Court.
Drake v. Jerejian	New Jersey	Lost on appeal at USCA3.
Peruta v. San Diego	California	Petitioned to U.S. Supreme Court.
Richards v. Prieto	California	Lost on rehearing at USCA9.
Woollard v. Gallagher	Maryland	Lost on appeal at USCA4.

There is a host of other right-to-arms cases that are working their way through the federal court system, but this is the vanguard litigation. A historical turning point is at hand, though some people can’t or won’t see the important civil-rights implications at work here. Few people need to carry guns, they argue, but then very few people needed to abort pregnancies … or to marry the spouses of their choice … or to ride at the front of the bus.