Regmaglips

Fragment of the Sikhote-Alin meteorite with pronounced regmaglips

Regmaglipts (from Greek: ῥῆγμα - “crack, scratch” and γλυπτός - “sculpted, carved”) - characteristic depressions on the surfaces of meteorites , resulting from the “drilling” action of the Earth’s atmosphere on meteorites during their movement in the atmosphere with space speeds ^[1] . A synonymous, but less commonly used term is “piezoglipts” ^[2] .

Regmaglipts can have a variety of shapes: round, oval, elongated, polygonal ^[2] . It depends on the location of the surface on which the regmaglypts formed, in relation to the direction of the meteorite in the atmosphere. On the sides of the regmaglipts, as a rule, have an elongated shape; on the back surface, as well as on the concave parts and in the hollows, a round or polygonal shape is more common ^[3] .

Regmaglipts are often compared with dents made by fingers in soft clay ^{[2] [4]} . Their size varies from a few millimeters to several centimeters in diameter.

Regmaglypts are formed at the last stage of a meteoroid’s flight in the atmosphere, when its speed decreases significantly, the shock wave weakens or completely disappears, and the body itself is fragmented. This is confirmed by the fact that the size of regmaglypts is directly dependent on the size of the fragment ^[5] .

On iron meteorites, regmaglipts are more pronounced than on stone ^[4] . Some meteorites do not have regmaglipts at all and have a completely smooth surface: this happens if the meteorite had a rotational motion during its fall ^[2] .

Regmaglipts are one of the most characteristic signs of meteorites, regardless of type and class, and serve to distinguish them from bodies of terrestrial origin ^[3] . However, it should be borne in mind that the presence of characteristic "pits" on the surface of the sample is not a decisive criterion in its definition as a meteorite. Depressions similar to regmaglipts can also be present on ordinary stone ^[6] .