Tears of Saint Lawrence

The popular name given to the Perseids. It is one of the most important meteor showers of the year, caused by the entry into the Earth's atmosphere of small rocky and ice remnants shed by comet Swift-Tuttle along its orbital path around the sun. When the Earth crosses that comet's orbit, our planet's gravitational field intercepts many of those small cometary particles, which begin a dizzying descent through the atmosphere. Along that path, friction with the air extraordinarily heats the small fragments, ionizing the narrow channel through which each one travels, resulting in the observed luminous trace. The name Perseids refers to the constellation Perseus, as that is the region of the celestial vault from which these shooting stars appear to originate. The name "tears of Saint Lawrence" dates from the 19th century, as the peak of the Perseids at that time coincided with the night of August 10-11 (Saint Lawrence's feast day is celebrated on August 10). Today, the peak has shifted to August 12, due to changes undergone in the comet's orbit as a consequence of gravitational perturbations. Shooting stars, due to their nature as photometeors, are of meteorological interest. The same applies to non-cometary rocky fragments that also cross the atmosphere. These meteoroids, as they fall, sometimes generate blinding flashes of light, known as bolides or fireballs.