The remains of the recently vaporized inhabitants.
The 816-pound copper impactor projectile will sail through the roof of a sleepy comet bar, instantly vaporizing the inhabitants, the dance floor and hundreds of gallons of celestial alcohol, thankfully after most patrons have already gone home to their pods. The impact will be so violent that it will take out one of the shopping districts, a school, a dilithium storage yard and much of the transit depot. The resulting crater will eventually dislodge the remnants of the copper projectile, luckily the most scarce and valuable element on Tempel, as the locals have long since learned that you can't make everything from diamonds, platinum and ethanol. Once the brief period of angry Bush-bashing subsides, they will thank us. Really.