Scientists Solve the Mystery Behind the Oumuamua ‘ Alien Spacecraft ’ Comet

The astronomers operating the Pan-STARRS1 telescope on the island of Maui were not expecting to hit cosmic paydirt on Oct. 19, 2017—but they did. On what was otherwise an ordinary night of skygazing, they suddenly spotted what is easily the oddest comet ever detected. Its high speed—87 km per second (54 mi. per second)—and highly elliptical angle indicated that it originated from deep space, the first known interstellar object ever to enter our solar system. It was cigar shaped and, as comets go, tiny—just 115 m (377 ft.) long and 19 m (62 ft.) wide. [time-brightcove not-tgx=”true”] Most important, the comet—which was dubbed Oumuamua (Hawaiian for “a messenger from afar arriving first”)—actually accelerated during the latter part of its transit, more than the gravitational influence of the sun could explain. That left even sober scientists to speculate that the object might actually be an alien spacecraft, speeding up under its own power during its barnstorming of our solar system. In the years since Oumuamua’s discovery, most people have put aside the E.T. talk, but no one has yet explained how, in fact, the object defied traditional cometary physics and hit the gas as it was leaving our solar system. Now, at last, a new paper in Nature might have the answer—and it has everything to do with molecular hydrogen. Every comet that passes through our solar system speeds up on the way out. For one thing, as i...
Source: TIME: Science - Category: Science Authors: Tags: Uncategorized healthscienceclimate Space Source Type: news