According to a story on BBC.com, the radar observatory at Arecibo may have to cancel its mission to observe the asteroid Apophis.
Times are tough, I hear you say. And indeed they are.
But there’s significance here, over and above interesting data on a 300 meter wide rock, with a mass of 27 million tons, hurtling through space. The first is that Apophis stands a small chance of striking the earth. How small? Well, that’s what the mission is, or perhaps “was,” supposed to determine. And Arecibo, in Puerto Rico, is the only telescope that can make that determination.
What if Apophis does hit the earth? It’s only 300 m wide, after all. We can already calculate that it will come within 18,300 miles of us in 2036, but an uncertainty of only a few hundred meters could, given the complexities of gravitational mechanics, solar winds, and unknown objects in space, mean the difference between hitting or missing. That’s what Arecibo could determine when the asteroid makes a flyby in January 2013.
What if it hit? The object that caused the Tunguska event in 1908 has been estimated at a few tens of meters across. The resulting blast over Siberia was roughly equivalent to a decent sized nuke (10-15 megatons). An asteroid like Apophis would likely produce a much larger effect. It would obliterate any city it landed near and could cause tsunamis if it struck in the ocean.
Low probability stuff, no doubt, but possible. What would it cost to have Arecibo find out? Brace yourself: $2-3 million. That’s “million” with an “m,” roughly what we spend in 20 minutes in Iraq alone. Unfortunately, the National Science Foundation doesn’t have the money for the mission. In fact, it’s cutting Arecibo’s overall budget by about 25%, which leaves just enough to keep the observatory running.
Point is that actions have consequences, and this small incident shows how we are beginning to feel the consequences of spending $3-5 trillion (Bilmes-Stiglitz estimate) on eradicating non-existent WMDs in Iraq and hounding rag-tag Taliban light infantry in the mountains of Afghanistan and Pakistan. May be worth doing, but as the late Milton Friedman loved to point out, there’s no free lunch. Actions have consequences, and costs.