UPDATE (5 pm ET): Despite the overwhelming similarities between the mystery “missile” and the contrail of a rocket launch, there may be a very simple explanation: It could be an optical illusion.

As detailed by New Scientist, Jonathan McDowell, an astronomer from the Harvard-Smithsonian Center for Astrophysics who tracks space launches, says it was probably an aircraft passing overhead, rather than a vertical rocket launch.

“If it’s coming over the horizon, straight at you, then it rises quickly above the horizon,” said McDowell. “You can’t tell because it’s so far away that it’s getting closer to you – you’d think it was just going vertically up.”

ORIGINAL POST: Monday evening, something launched approximately 35 miles off the Californian coast. A news helicopter even filmed the rocket-like contrail rising like an arced pillar in the sunset. If seeing is believing, there was definitely a rocket launch of some description.

However, no one is claiming responsibility. The U.S. military seems baffled, U.S. airspace was not notified of any commercial satellite launches, no regional Air Force bases had any launches planned and all we’re left with are scores of theories as to what it might be.

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Interestingly, this isn’t the first time this has happened. As reported by IEEE Spectrum, on New Year’s Eve last year a rocket-like contrail was filmed by eyewitnesses off the coast of Orange County, Calif. Similar to last night’s weirdness, no one claimed responsibility, the military denied all knowledge and all we were left with was scores of conspiracy theories.

Naturally, the first thing that comes to mind when viewing last night’s video footage is that the object is a rocket launched from an ocean location.

Local news stations are all over this story, but on asking the U.S. Navy whether they had any ships in the region, they denied that they had fired any missile and said no ships were nearby.

The North American Aerospace Defense Command (NORAD) is working with U.S. Northern Command (USNORTHCOM) to investigate the mystery launch. They issued the following statement:

NORAD and USNORTHCOM are aware of the unexplained contrail reported off the coast of Southern California yesterday evening. At this time, we are unable to provide specific details, but we are working to determine the exact nature of this event. We can confirm that there is no threat to our nation, and from all indications this was not a launch by a foreign military. We will provide more information as it becomes available.

There’s some conjecture that this launch may have been a show of U.S. military might during President Obama’s visit to Asia. I have a few problems with this theory. For starters, if launching a solitary missile is an attempt at political maneuvering by the U.S. government, it’s a pretty weak display. Countless nations, big and small, have the ability to blast sizable missiles into the sky. Also, launching a missile a short distance away from Los Angeles International Airport — one of the busiest commercial airports in the world — without warning, is reckless to say the least.

Besides, what’s the point of the U.S. military launching a missile without claiming responsibility if it’s intended as a saber-rattling exercise? So where does this leave us?

We’ve seen countless rocket launches that resemble this mysterious contrail. Something was definitely launched (destination, so far, unknown), but when presented with few facts, it’s hard to draw any conclusions.

The only theory I have is that it was a missile launched by the U.S. military, but they wanted to keep it secret. Could it be a test of anti-satellite weaponry?

The U.S. and China have been developing surface-to-orbit missiles over recent years; perhaps this is another step in the development of these technologies. In this case — especially if the missile is unproven — the military would want to keep the launch secret to avoid any embarrassing mishaps like the recent Russian ballistic missile failure.

(Although the Russian ship-launched ballistic missile failed, causing some embarrassing political fallout, it sure was a beautiful sight.)

Even this theory is horribly flawed. Why would the anti-satellite missile be launched at sunset right next to one of the most populated coastlines of the U.S. if it was supposed to be a secret?

What do you think? Is this some covert military operation? Was the U.S. even responsible?

Image credit: CBS8