The annual Perseid Meteor Shower is happening now! The meteors are the remnants of Comet Swift-Tuttle, and every August, like clockwork, our planet Earth cuts through the “river of rubble” left behind along the orbit of the comet. And yet, while comets are composed chiefly of frozen gas, meteors are very flimsy. They’re material that has flaked off comets and they’re similar in consistency to cigar ash; they litter up our solar system. Most are scarcely larger than pebbles or sand grains.
In the case of the Perseids, they come crashing into Earth’s atmosphere at estimated speeds as high as 37 miles per second—133,000 miles per hour. These tiny visitors from the cold, vast voids of stellar space, have been orbiting in the solar system for perhaps hundreds or even thousands of years, but cannot survive the shock of entry, and end up streaking across the sky in a brief, blazing finale lasting but a few seconds. Their kinectic energy is used up in such processes as the production of light, heat and ionization. Thus, such a tiny particle bursts into incandescence from friction, producing the shooting star effect and can be seen from more than 100-miles away. But it’s really the light energy it develops, not the particle itself that we see.
They are named the Perseid meteors because their fiery trails, if extended to a common point of intersection, would seem to originate near to the Double Star Cluster in the constellation Perseus, which on mid August evenings rises from the northeast.
Get tips on how best to view the Perseid Meteor Shower from NASA.