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The Flash to Bang Count: Observations on the October Indonesian Asteroid Airburst

A few days ago, The Telegraph reported:

"An asteroid that exploded in the Earth's atmosphere with the energy of three Hiroshima bombs this month has reignited fears about our planet's defenses against space impacts. On 8 October, the rock crashed into the atmosphere above South Sulawesi, Indonesia. The asteroid was around 20 meters across and hit the Earth's atmosphere at 45,000 mph. The blast was heard by monitoring stations 10,000 miles away, according to a report by scientists at the University of Western Ontario. Scientists are concerned that it was not spotted by any telescopes, and that had it been larger it could have caused a disaster. Luckily, due to the height of the explosion - estimated at between 15 and 20 km (nine to 12 miles) above sea level - no damage was caused on the ground."

Later reports mentioned and estimated 5 to 10 meter diameter for the asteroid. Let's consider the implications of this event. If this had happened in the skies over a First World nation, or if the explosion had taken places at ground level (or near ground level, a la the 1908 Tunguska event), then there would be a huge clamor and calls for early asteroid impact prediction, and greater preparedness. But since this took place above what most consider a backwater nation, and there was no visible damage on the ground to photograph, this news story was resigned to "minor headline" status. And what if the object had been 100 meters in diameter, instead of 20?

We've previously discussed asteroids with Earth-crossing orbits--also known as Near Earth Objects (NEOs)-- and the consequences of potential impacts in SurvivalBlog.

Asteroid impacts are one of those "low likelihood but high disruption" events. The chances of one occurring in our lifetimes is relatively low, but if one were to happen, the implications would be huge. In anticipation of future asteroid impacts, here are some factors to consider:

• An asteroid impact could cause short-term climate change that could in turn cause multi-year crop failures on a hemispheric or even global scale. This means that it would be prudent to have multiple years food storage
• The importance of living in inland areas. Let's face it: coastal areas anywhere on earth are vulnerable to mega-tsunamis, if you factor-in the threat of asteroid impacts. Unless there is some massive intervening terrain, don't live at less than 500 feet above sea level if you must live within 25 miles of an ocean. A 300+ foot high tsunami might seem hard to imagine, but just ask an astrophysicist. It is possible, and in fact there is some geologic evidence that that mega-tsunamis have occurred in the past 6,000 years.
• Never underestimate the implications of mass hysteria and misdirected government reaction to a crisis. News of imminent crop failures might inspire executive orders mandating the collection of "hoarded" food. Hint: This will probably include food that you started storing years ago--long before any imminent threat warning or post-incident panic buying. So I must again warn my readers that it is wise to keep a low profile about your preparations.

I have been studying the threat of asteroid impacts for many years. NEOs represent a "wild card"scenario. Since a fairly complete orbital path tracking database probably won't exist for 20+ years, this threat will remain an imponderable for the foreseeable future. Until a fully-populated database is developed, this will remain a quasi-voodoo science. The Indonesian event illustrates just how easy it is to get blind-sided. And even after we have complete tracking data, it will be decades longer before we start to proactively develop a program to "nudge" the larger NEO asteroids into safer orbits.

But again, keep in mind that this is one of those "low actuarial risk/high consequence" events. Plan accordingly.

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