Free Astronomy Magazine May-June 2020

36 falling is quite widespread, and it is by now a custom for ama- teur associations to organize public events on the occasion of the peaks of the most fa- mous meteor showers. Although they are familiar to almost everyone, and although astronomers and meteorolo- gists know nearly everything about this phenomenon, there may be an exotic type of me- teor that so far no one has ever seen: the sub-relativistic me- teor. As you can guess from the name, the original meteoric material would travel through interstellar space at very high speed, measurable in non-neg- ligible fractions of the speed of light (the conditional here is a must). Occasionally, very small agglomerations of this material would strike the atmosphere of our planet, producing effects different from those typically generated by ordinary meteors. A bright meteor rushes over the Atacama Large Millimeter/sub- millimeter Array. [ESO/C. Malin, 2014] On the left, two Perseids in the vibrant sky of the Himalayan Chandra Telescope at 4500 meters elevation. The light from Mars is reflected in the dome. [Chirag Upreti, 2018] Below, another Perseid, captured this time in the night sky above the four Very Large Telescope domes. [ESO/ S. Guisard, 2010]