Scientists have revealed a series of three mysterious impact craters on the surface of the Moon.

Dubbed the 'three amigos' by experts operating the Lunar Reconnaissance Orbiter Camera which took the images, experts believe the craters formed within minutes of each other - but have no idea how.

They believe the bizarre arrangement may have been caused by a meteorite or comet breaking up - or three separate impacts occuring in a unique coincidence.

Moon Impact Craters
© NASA/GSFC/Arizona State UniversityThe 'three amigos' spotted on the surface of the moon, with debris sprayed upto 1km away.
'These three craters, located at 9.665°S, 7.646°E, appear to have formed more or less at the same time, certainly within a few minutes of each other,' the researchers say.

'The southwest crater is 180 m diameter; the center crater is 150 m; and the northeast crater is 125m across. 'From the northeast crater center to the southwest crater centers, they cover about 450 m.'

The team has calculated that the projectiles were traveling from the east-northeast (the right side of the frame) and probably struck the surface at a relatively low angle, as indicated by the dust and other material they threw up - which extends as much as 1 km from the crater center.

Moon Impact Craters_1
© NASA/GSFC/Arizona State UniversityThe same scene as above in afternoon lighting. The low Sun accentuates the subtle topography associated with the impact craters, researchers say.
'The morphology of the craters suggests that the southwest crater formed first, followed by the other two,' the researchers who analyse data from NASA's Lunar Reconnaissance Orbiter Camera.

The southwest crater may only have formed a few seconds or a few minutes before the other two, the team believe.

The shape of the two northeast craters (the low northwest-trending ridge between the craters) suggests that the projectiles hit the surface at the same time such that the excavation process of the two craters interacted, forming the ridge.

Moon Impact Craters_2
© NASA/GSFC/Arizona State UniversityThe three craters were formed withing minutes of each other, causing the unique ridges between them.