A £255million satellite that will monitor the Earth's atmosphere has successfully launched into space.
But conspiracy theorists believe something overshadowed the 'perfect' launch on Kyushu Island in Japan.
They claim an unknown 'mysterious craft' passed closely by the rocket as it travelled at 25,000mph - and some think it could be aliens monitoring our technological advances.
Thousands of people gathered to watch Japanese Space agency Jaxa launch its Epsilon 3 rocket at 6.06am on January 18.
Video shows that shortly after the craft engaged its secondary boosters a UFO , allegedly flying at the same altitude as the rocket, appeared.
The object was made up of three white lights and a red blinking beacon that appear to swoop close to the rocket.
Many viewers have pointed out that the lights look like they belong to a plane.
But conspiracy theorists insist a no-fly zone was in place during the launch.
UFO Today posted footage of the launch on its YouTube page.
The caption read: "Many will say this is an airplane, but the area had a no fly zone at the time of the rocket launch.
"The launch went perfectly, but during the launch a strange mysterious craft was filmed. This UFO was flying at the same altitude as the rocket.
"It was moving along with the rocket as it started it's orbit around earth. What was this object?"
But not everyone was convinced the lights were extra-terrestrial in origin.
One viewer wrote: "It's got an FAA light blinking...so....it's human made."
Anther added: "That's an airplane, there's a blinking light on it and UFOs don't normally have blinking lights."
The third Epsilon rocket was carryin the ASNARO-2 radar-imaging satellite into orbit.
Almost 45 minutes after lift-off the 570-Kilogram radar satellite separated from the rocket.
The satellite, developed by the Institute for Unmanned Space Experiment Free Flyer, will take images of the Earth to monitor the atmosphere.