Asteroid 2007 WD5 whizzed by Mars today unencumbered by any massive objects, like Mars itself. I was hoping for an impact so that the debris kicked up into the Martian atomosphere could be analyzed. Who knows what may have been discovered?

Steve Chesley, an astronomer at the Jet Propulsion Lab said that impacts of a 164 foot asteroid like 2007 WD5 can be expected to occur only once in a thousand years, while near misses happen frequently, perhaps every ten to twenty years.

Mars is a smaller catcher’s mitt for these spaceballs to hit, and missed Mars by 6.5 Mars radii. There will be others and I will be looking out for them.

Somewhat unsettling is the news that researchers now say the asteroid that impacted Tunguska, Siberia a hundred years ago wasn’t nearly as large as previously thought, according to supercomputer simulations by Sandia National Laboratories physicist Mark Boslough. He estimates the blast force of that asteroid to be 25% to 33% of the 10 to 20 megaton blast force previuosly believed. This means that smaller asteroids hitting earth may in fact create larger blast zones than previously thought.

The simulation shows the asteroids mass exploded above ground shooting a fireball downward into the ground faster than the speed of sound. Botton line – it takes less energy than thought to create devastation from an asteroid.