How to Watch this Week ’ s Spectacular Geminid Meteor Shower

Harvard astronomer Fred Whipple thought he did not have much to show for his night’s labors on Oct. 11, 1983. Yes, working with NASA’s Infrared Astronomical Satellite, he had discovered an entirely new cosmic object—which is always a nice thing to put on the scientific tote board. But that object was an unremarkable one. Measuring only 5.1 km (3.17 mi.) across and dimly illuminated, it was thought to be either a dead comet—one that had lost its ices and other volatiles after repeated passes by the sun; or a rock comet, which also lacks volatiles, but which nonetheless gives off tail-like particles like a comet does as it approaches the sun and the growing heat gives rise to cracking and splintering of the object. [time-brightcove not-tgx=”true”] Whipple gave his new object the name 3200 Phaethon: the 3200 part is a technical designation intended for astronomical catalogs; the Phaethon portion was a nod to the fact that the rocky body moves closer to the sun than any known asteroid—just 21 million km. (13 million mi.) away—leading Whipple to name it after Phaethon, the son of the sun god Helois in Greek mythology. And that should have been that for Whipple’s modest rock. But 3200 Phaethon turns out to be worth more than just that—and indeed is the source of one of astronomy’s greatest sky shows. The object takes about 1.4 years to make a single rotation through the solar system. In its wake it leaves a de...
Source: TIME: Science - Category: Science Authors: Tags: Uncategorized healthscienceclimate Source Type: news