We will have a celestial visitor to our neighborhood on the 26th of January as asteroid 2004 BL86 passes by the Earth at a distance of about 745,000 miles (1.2 million kilometers). This is about three times the distance from the Earth to the Moon, so we don’t have anything to worry about—this time.
Asteroid 2004 BL86 Flyby – Image courtesy of NASA/JPL
But, what if it wasn’t missing us? What if it had a direct bead on Earth? What would we be doing today? Would Putin still be fanning the flames in the Ukraine? Would ISIL still be executing innocent people in their quest of world domination? Unfortunately, I think that the answer to these questions is probably yes – unless there was no doubt about 2004 BL86 landing in their back yard.
So, what would be the consequences of this asteroid hitting Earth?
First off, it’s not moving that fast—relatively speaking—56,520 km/h (35,120 mph), so it’s energy upon impact at about 6000 Megatons of TNT or 300,000 times the yield of the bomb dropped on Hiroshima, Japan (20 Kilotons of TNT). It could be a lot higher. (That’s a scary thought in its own right!)
The crater that would be left would be 4.7 miles (7.6 km) in diameter and have a depth of 1780 feet (544 meters) covering an area of (17.3 sq miles/45 sq km). The size of the crater alone would wipe out any major city on the planet, but the devastation would extend well beyond that from the fireball generated by the impact, high pressure atmospheric shockwave and seismic shock extending out to a distance of almost 60 miles (100 km). We are talking about tens of millions of people that will no longer exist in instant and millions more that will suffer from the after effects. (The numbers used here come from the calculator: Impact Earth.)
Remember, this is a small chunk of rock!
If it hit in the ocean, say a 100 miles (161 km) off a coastline in about 1000 feet of water, the tsunami waves generated could be between 29.2 feet (8.9 meters) and 58.4 feet (17.8 meters) high and would affect other coastlines around the world to a lesser degree. The size of the wave will change depending on where the asteroid hits the ocean relative to its depth and proximity to the coastlines.
The impact of 2004 BL86 wouldn’t end the world by any means, but it could kill many people and have global impact on international businesses and economies for years to come. The money that each country spends today on defense is money that should be spent on defending this planet from an impact that is surely to come sometime in the future—near or far. We are able to identify many of these objects as to the risks they pose to our planet, but we have not put forth a unified effort on preventing an impact should one be found coming our way. That technology is at hand but needs to be developed and refined.
Please note that the purpose of this exercise isn’t to scare people but to point out that Mother Nature has powers at her disposal that make our most formidable weapons pale in comparison, and the battles we fight on this spec of dust in the cosmos are insignificant. We’ve spent way too much time plotting against each other instead of planning a course of action that will benefit us all. Time marches on and we may be just running out of time to put up a good defense.
So, enjoy asteroid 2004 BL86 as it passes by—there will be plenty of media coverage—and be glad it’s not coming to stay permanently!
Till next time,
RC Davison