The two Trident II (D5) missiles were launched from an Ohio Class submarine off the coast of California, causing a bright light to streak across the California sky.
The first test occurred at 3:30 a.m. and the other at 6:20 a.m.
Many Bay Area residents who saw the unusual light were left guessing at what it could have been.
Daniels said missile flight tests such as this this are kept hidden from the public until after they occur for security purposes, but that they are done as part of routine training and on a frequent basis to ensure reliability of the systems.
"If we said we are going to do a missile launch from such and such place at such and such time, that creates a vulnerability for some of our submarine and assets out there," Daniels said.
Loren Thompson, a military analyst at Lexington Institute, said that the U.S. military needs to reconcile safety with secrecy because if a foreign country were to monitor a missile launch, they would be able to gather intelligence about how it operates and potentially use that knowledge in the future to defeat it.
"You have to let people endangered by the launch out of the area, but you don't want foreign countries, particularly Russia, to be able to monitor the missile's trajectory," he said.
However, the Navy does notify some countries that it has treaties with that it will be conducting a missile exercise in order to avoid setting off alarm, Daniels said, and it also notifies aviation and sea personnel to stay clear for a certain period to ensure their safety.
"At no time did the missiles fly over land. They are tracked from multiple sources from launch until final impact in the ocean," Daniels said.
The Trident II (D5) missile is the backbone of the U.S. military’s ability to deter a nuclear attack and was built by the space system business unit of
It's been in use since the late 1980s and has an impeccable track record, with over 100 consecutive launches without a single misfire, according to Thompson.
"The only mission the Trident II (D5) missile and submarine has is to deter a potential nuclear attack against the United States," Thompson said.
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