Two researchers at Brown University, looking at infrared images of the surface of Mars, noticed strange streaks radiating from impact craters. They offered an explanation of their find in an article in the Icarus magazine.
Scientists have found that the stripes they found extend further than the usual relief features formed when a meteorite or other body strikes the planet's surface. The authors of the study suggested that the cause of the stripes could be tornado-like vortices caused by the fall of the meteorite. The wind speed in them could exceed 800 km / h. This wind blew away dust and debris and exposed more solid rocks.
When an asteroid and a planet collide, tons of matter from both bodies evaporate, and jets of gas escape from the impact site at very high speeds. By interacting with the planet's atmosphere, they caused very strong winds. By themselves, such air currents pass over the surface of the planet, however, colliding with rocks, they formed the very vortices.
The images were taken with the Mars Odyssey orbiter, its THEMIS instrument, which captures the planet's surface in the visible and infrared spectrum. They show the difference in heat absorption by different parts of the surface. “You wouldn't be able to see these details in any image in the visible spectrum, but infrared radiation at night makes them very bright. Harder rocks become brighter and retain more heat than surfaces covered with dust and debris,”said one of the scientists who worked on the article, researcher at Brown University Peter Schultz.
However, one more question remains open: why do all these processes (and the formation of stripes) occur in some collisions and not in others? The authors of the work hope to get an answer by continuing the research. Scientists suggest two versions. According to the first, super-powerful vapors caused by a meteorite impact and leading to vortices are associated with the characteristics of the soil. According to the second, the vortices are caused not by meteorites, but by comets.