Missile tests like the one the Navy performed off the coast of Southern California on Saturday night present military officials with something of a conundrum.
On the one hand, said Loren Thompson, a military analyst with the Lexington Institute, the military needs to give local aviation officials enough information as to the time and place of an upcoming test to ensure no planes are in the area.
But at the same time, the military is determined to keep tests shrouded in secrecy in order to thwart any efforts by potential adversaries -- namely Russia and China -- to monitor the missile launch and flight, Thompson said.
The confusion and social media uproar that erupted Saturday night as a mysterious white cone of light coursed across the night sky is an unfortunate but necessary tradeoff, Thompson added.
The need for secrecy was all the more important given the type of weapon the Navy launched Saturday from a submarine, according to Thompson.
The Trident II (D5) missile is a centerpiece of the U.S. military's ability to deter a nuclear attack and modernizing the weapon is a top priority, he said.
Knowing in advance that a Trident was going to be tested would give prying eyes, for example sailors on a Russian submarine positioned in the Pacific, the ability to gather valuable information, Thompson said.
Tracking its trajectory, speed, electromagnetic emissions and other characteristics in real time could provide insights into potential vulnerabilities, Thompson said.
This is especially true during the first stage of flight, the "boost phase," when the missile's rockets are firing and the weapon is most susceptible to attack, Thompson added.
"The Russians and Chinese would have great interest in finding ways to defeat this type of missile," he said.
Witnesses across Southern California and Arizona posted video and reported seeing the light. Many used hashtags such as #ufo and #comet as they speculated about its source.
Video blogger Julien Solomita was on a rooftop parking lot in Van Nuys shooting traffic and sunset scenes when he looked up and saw a bright circle of light in the sky. He followed it with his camera and at one point, he said, it looked like it was exploding.
"For a brief moment, when the cloud got bigger, I was wondering, 'Should we run?' It looked so close," he said.
Since it was posted, his YouTube video has gotten nearly 1.5 million views and has been widely circulated on social media, helping to set off a furious round of speculation -- was it a UFO? A missile? A comet?
Solomita says he's still not satisfied with the official explanation.
"I'm not 100% convinced I know what happened no matter what news channels are saying. I'm kind of remaining skeptical because we were there, and it was crazy," he said.
If it was a missile test, he said, the public should have been better informed.
"Why do a missile test over the second largest city in the U.S. and not tell anyone? That's pretty wild," he said.
The missile test, first reported by the San Diego Union-Tribune, was part of a scheduled, ongoing system evaluation, a Pentagon spokesman told The Times.
Launches are conducted on a frequent, recurring basis to ensure the continued reliability of the system, the spokesman said.
Times Staff Writer W.J. Hennigan contributed to this story.