Let’s Shoot Down a Satellite: An In-Depth Review (Part 2)

There were many reasons why U.S. Defense Secretary Robert Gates gave the order to shoot down spy satellite USA-193 (NROL-21). First, the American spacecraft could have killed or injured many people had it re-entered Earth's atmosphere. There was also sufficient evidence that the fuel tank would withstand re-entry because the space shuttle Columbia had a similar tank which survived and struck the ground after its tragic loss in 2003. Still, MIT physicist and space expert Geoffrey Forden calculated that there was only a 3.5 % chance that the spy satellite's fuel tank would kill or injure a human if it survived atmospheric re-entry.

Another reason for the Pentagon's "go" decision was concern that hydrazine fuel poses an unacceptable risk to humans and the environment. Any person who breathed the toxic fuel would need immediate medical attention and, because of the airborne nature of fumes, the fuel could spread quickly depending on the wind and weather conditions. Many experts, including former Assistant Secretary of Defense Philip Coyle, did not accept this argument. Instead, they believed that that the National Reconnaissance Office (NRO) did not want some part of the satellite falling into the wrong hands. According to these critics, the NRO had its own reasons for the satellite needing to be shot down, and could not (or would not) share this information with the general public.

On February 20, 2008 at 9:07 AM, the space shuttle Atlantis landed safely at Cape Canaveral, Florida. With the space shuttle and its crew safely on the ground, U.S. Defense Department officials said that the window of opportunity was now open. The U.S. Navy positioned three ships, the cruiser USS Lake Erie and the destroyers USS Decatur and USS Russell, in the Pacific Ocean, waiting for the optimal launch time. They waited for all factors to be in their favor before shooting. Steady seas were needed around the Navy cruiser that would fire the missile, optimum positioning of the spy satellite was required as it passed in polar orbit, and space and ground sensors needed to be ready to track the results.

Early Wednesday morning, a senior military officer said that the weather wasn't good enough for an ASAT launch. Hours later, however, another officer said that the weather was improving and that a launch might be possible by Wednesday night. The next obstacle the Navy faced was high seas in the North Pacific. Rough seas could interfere with the cruiser's launch procedures, and positioning could become problematic.

The U.S. government had put several precautionary and safety procedures in place. Operating under the code name "Burnt Frost", hazardous materials teams were ready to be deployed immediately anywhere in the world, to the site of dangerous or sensitive debris. Authorities had also dispatched six Federal Emergency Management Agency (FEMA) teams across the country for a worst-case scenario. The U.S. government also made worldwide notifications to mariners and aviators, warning them to stay clear of a large area in the Pacific Ocean where the most debris might fall. At the same time, however, experts agreed that the risk which falling debris posted to commercial aircraft was low enough that planes would not need to be rerouted around the area.

Yet risks remained. If the Navy missile struck the spy satellite, there was only a 30% chance that the fuel tank would be destroyed completely by flying shrapnel. At the same time, the U.S. military was concerned about the possibility of missing the satellite completely due to the incredibly high closing speeds and long distance involved. They were also concerned about the political and military fallout if such a failure occurred.

Editors Note: Part 1 can be found here on CR4 and Part 3 will run tomorrow.

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