NASA astronaut sees mysterious bright green flash during stay on ISS

A NASA astronaut aboard the International Space Station (ISS) captured stunning video of a bright green explosion that occurred more than 250 miles above Earth.

Astronaut Matthew Dominick captured video of the mysterious light and asked the public for help identifying the source of the flash.

“I showed this to a couple of friends yesterday to see what they thought. They both thought it was a meteor exploding in the atmosphere – a fairly bright one called a bolide,” he wrote on X.

According to NASA’s Center for Near Earth Object Studies, a bolide is an exceptionally bright meteor that is spectacular enough to be seen over a wide area and that explodes in Earth’s atmosphere.

Bolides are a type of “fireball,” meteors that reach a brightness greater than magnitude -4. That’s about as bright as the planet Venus seen in the morning or evening sky, according to the American Meteor Society (AMA)

The difference between boldies and fireballs is that boldies explode once they enter the Earth’s atmosphere, as Dominick captured on video.

When a meteor enters Earth’s atmosphere, friction causes the meteor to slow down and heat up at the same time.

The force of the impacting meteor causes a ‘bow shock’ to be created for the meteor. A bow shock is a shock wave that occurs when a supersonic object moves through a medium, such as atmospheric gases.

The bow shock heats and compresses the atmospheric gases in front of the meteor, and some of this energy is radiated back into the meteor. This causes the meteor to ablate – or erode – and eventually break up.

The resulting fragmentation increases the number of objects hitting the atmosphere, thereby enhancing atmospheric ablation, further slowing the meteor.

The meteor explodes when the force created by the unequal pressure on the front and back exceeds the tensile strength, which is the maximum amount of stress an object can withstand before it breaks apart.

When a meteor is destroyed in this way it is called a “boldie.”

According to the AMA, thousands of fireball-magnitude meteors occur in Earth’s atmosphere every day. But not all of them become boldies.

These exploding meteors are relatively rare and difficult to spot, as their flashes last only a few seconds.

Dominick was lucky enough to capture this moment when he filmed a timelapse of Earth as the ISS flew over North Africa.

Shortly after the space station flew over Cairo, Egypt, a bright explosion flashed green and then white across our planet.

“Timelapse was set up over North Africa where it was very dark with lightning. I got greedy with ISO (25600) and when the timelapse got to Cairo the cities were overexposed,” he wrote in a post on X, formerly Twitter.

“I was greedy because I wanted the Milky Way core. When I looked at the pictures later, I found the bolide.”

The astronaut posted two videos of the event: a time-lapse showing the flash in slow motion, and a sped-up version.

Both show the meteor streaking over Cairo, Egypt before bursting into flames.

Dominick flew to the ISS in March as commander of NASA’s SpaceX Crew-8 mission.

Over the past five months, he has shared countless photos and videos taken from his vantage point high above our planet.