A still image showing the light from Asayevich’s video. (Juliana Asayevich / Facebook) — A still image showing the light from Asayevich’s video. *(Juliana Asayevich / Facebook)*

London, England resident Juliana Asayevich shared a video to the Canary Wharf & Isle of Dogs Residents Facebook page on August 15th which appears to show a mysterious light emanating from the depths of the River Thames.

"I have just seen this in the river. Any ideas what it could be?" she asked in the post.

Responses to Asayevich’s inquiry ran the gamut from helpful to comedic.

"Someone's thrown a traffic beacon in maybe, they take a while to stop working—pretty waterproof," commented Jessica Dallamore.

While Russell Smith joked, "It's a UFO. Unidentifiable floating object."

Other ideas included a lost cellphone or even a submarine.

"That looks like a submarine. Maybe the SAS doing a secret mission," Sally Stocker commented. "I’ve heard they use the Thames for training sometimes."

This may not even be the light's only appearance, since Alice Sturza, also of London, said, "I saw it last night next to Island Gardens. It looked like a small walkie talkie, with a flashlight at the bottom end, flashing."

Island Gardens is roughly two miles downstream from Canary Wharf; if somehow Sturza had seen the same light, it had travelled against the current to be in position for Asayevich to spot it.

The mysterious light may very well have a prosaic explanation, but some viewers’ thoughts turned to the otherworldly as several people speculated its cause to be “aliens.”

That association, even if tongue-in-cheek, shouldn’t be a surprise, given talk within the UFO community of objects observed by military personnel to have "transmedium" capabilities, such as submerging underwater from the air.

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