Bizarre sighting by aircraft passengers; UFO or giant bird?

UFO videograb
Representational picture only: UFO video grab from Youtube Jason Gleaves, Ufonly

Kerry Forides, an aircraft passenger has shot a video featuring a weird UFO in the skies during his flight to Greece. The video, posted on YouTube by New York Post, has gone viral on various social media platforms attracting more than 740,000 views.

According to conspiracy theorists, the UFO featured in the video has performed several maneuvers which would be impossible for any known aircraft on the earth to pull off. The clip was reportedly shot when the plane was somewhere above the Aegean sea.

As the video went viral, people started coming out with various explanations behind the weird incident. Many people claimed that this video is an evidence of alien existence, and blame the government for not conducting investigations on these sightings.

On the other hand, skeptics have already debunked the UFO theory, and they strongly assure that it could be either a giant bird or the contrail left by another aircraft flying nearby.

"It's a rocket or something like space X. The smoke-like trail appears dark because of the shadow of the rocket. If it is aliens why they are always hiding to us? Haha, are they shy? Or they said that aliens are using hi-tech then why they fail to hide their spaceship to the earthers," commented brain fartTM, a YouTube user.

Another YouTube user sarcastically commented that the object is nothing but SpaceX founder Elon Musk going to the shop for buying milk.

This is not the first time that UFOs are captured from aircraft. Last month, two pilots from two different flights have reported UFO sighting over Southern Arizona. A couple of weeks ago, a veteran Argentinian pilot had reported a UFO sighting while he was on a private flight.