A Danish astronaut recorded the creepy moment "elusive blue jets" burst from a distant cloud in footage which has raised more questions than answers.
Despite using the station's most sensitive camera, the strange "activity" recorded over the Bay of Bengal remains a mystery.
It was perplexed scientists so much that the European Space Agency (ESA) are set to launch several experiments this year to "monitor the pulsating blue jets" shooting up out of clouds.
For years, the existence of the gigantic blue discharges has been debated, with the scientific community largely dismissing them – despite contrary reports from astronauts in space.
The astronaut behind the footage said the cloud are something 'we know very little about'
ESA astronaut Andreas Mogensen, who captured the footage, said: "It is not every day that you get to capture a new weather phenomenon on film, so I am very pleased with the result – but even more so that researchers will be able to investigate these intriguing thunderstorms in more detail soon."
But for now, Mr Mogensen reiterated that "it's something that we know very little about".
The ESA added: "The blue discharges and jets are examples of a little-understood part of our atmosphere.
"Electrical storms reach into the stratosphere and have implications for how our atmosphere protects us from radiation."
Further studies into the strange event are taking place later this year
The bizarre weather incident was caught over the Bay of Bengal
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It's something that we know very little about
The Danish-led investigation, named the Thor Experiment, into the "astonishing blue jets" confirmed that the beams grew to 25 miles out of the cloud before fading away.
The beams can move at speeds of up to 360,000kph (220,000mph) and without a high speed camera can be easily missed by the human eye.
Further studies into the strange phenomenon are planned for later this year, as part of a project to monitor the "transient luminious events".
Shot from the ISS, the footage raises more questions than answers
Olivier Chanrion of the Danish National Space Institute in Lyngby: "We wanted to see what happens above a thunderstorm.
"What we see is that at the top of the cloud in what we call the 'turrets', there is incredible activity.
"They were dancing over the top of the cloud, and we called them glimpses.
"But it's only a first step and we need to find out more."