Most accounts suggest that the 2017 Geminid meteor shower made for an impressive sight last week. But that might also have been the result of the presence of 3200 Phaethon, an asteroid and so-called “rock-comet” that was expected to fly by Earth this past weekend and is also believed to be the driving force behind the meteor shower.
According to a report from EarthSky, it was unsure at first if the Geminid meteor shower would be “extra rich” at the time it was supposed to peak last week, on December 13 and 14. This was compounded by the unusual qualities of 3200 Phaethon, which has been described as a three-mile wide asteroid that could cause major regional damage if it ever hit Earth. On the night of Saturday, December 16, the object made its closest approach to Earth, just as expected, in an orbit period that is estimated to last 523.5 days.
While astronomers were right on the fact that the 3200 Phaethon asteroid spared Earth when it made its close flyby over the weekend, EarthSky found it more interesting that the object seemingly drove an excitingly rich Geminid meteor shower, just as one would expect if a parent object is close to a meteor shower. That said, the publication noted that amateur and professional astronomers alike were able to capture the asteroid in photos and/or videos as it made its flyby.
As noted by Newsweek, 3200 Phaethon shares a name with the son of Helios, the Greek sun god, as the object is also known to make extremely close approaches to our sun. In 1983, it also became the first asteroid to ever be explored via spacecraft, two years before it was given its name and its number. But while most publications refer to Phaethon as an asteroid and nothing else, EarthSky explained that it is actually more of a “rock-comet,” or a cross between an asteroid and a comet that “[blurs] the distinction” between both types of celestial objects, and one of the first of its kind to be spotted and identified by scientists.
— ABC7 Eyewitness News (@ABC7) December 15, 2017
Further explaining why 3200 Phaethon cannot be considered a traditional asteroid, EarthSky added that asteroids have a more metallic composition than comets and usually make more circular orbits, as compared to the elongated orbits comets often make. Based on its orbit pattern, Phaethon behaves more like a comet than an asteroid and also has the peculiar tendency to emit dust and sport a dusty tail.
Although the 3200 Phaethon asteroid/rock-comet made a rather close encounter with our planet when it flew by quietly on Saturday, that doesn’t change the fact that it is considered a “potentially hazardous asteroid.” While it never was a threat to Earth, 3200 Phaethon is noted for its size of three miles (five kilometers) wide, which makes it “big enough to cause significant regional damage” if it were to hit our planet. Fortunately, scientists have spent a lot of time analyzing the object’s orbit and have assured that there is no upcoming asteroid strike due to take place “in the foreseeable future.”