For the most part, we count on the Observer’s Handbook to provide us with the peak dates for the year’s major meteor showers. The Observer’s Handbook 2018 lists November 5 (at 18:00 Universal Time) as the peak time for the 2018 South Taurid meteor shower. We find this prediction re-echoed in Sky & Telescope magazine’s Skygazer’s Almanac 2018 as well as other publications.
Yet two other trusted sources give different dates for the South Taurid peak. The International Meteor Organization (IMO) says the night of October 9-10. The American Meteor Society (AMS) says the night of October 28-29, claiming that this shower:
… rarely produces more than five shower members per hour, even at maximum activity.
Astronomer Guy Ottewell, in his 2012 Astronomical Calendar, helps to explain the discrepancy for the peak date of the South Taurid meteor shower. He explained:
Fresh IMO evidence suggests the Southern branch, rather than reaching its maximum in early November as long believed, actually has its peak in October instead.
Whenever this year’s peak may happen, it’s probably safe to assume that the long-lasting South Taurid meteor shower (September 10 to November 20) will display no sharp peak.
These South Taurid meteors steadily amble along for weeks on end, rarely exhibiting any more than five meteors per hour! So the moon’s phase may be more of a consideration than the peak date. This year, in 2018, the bright waning gibbous moon obtrudes on the show on the night of October 28-29, whereas there is no moon to ruin the display on nights of October 8-9 and November 4-5.
From what we have been able to gather, the Taurid meteor stream consists of an extremely wide roadway of far-flung debris left behind by Comet 2P/Encke. When Earth travels through this belt of comet debris, bits and pieces of Comet 2P/Encke smash into the Earth’s upper atmosphere to vaporize as rather slow-moving Taurid meteors (28 km/17 miles per second).
Yet, the Taurids are known for having a high percentage of fireballs.
Apparently, the original Taurid stream had been perturbed by Jupiter into two branches: South and North Taurids. The South Taurids, the more prominent of the two, are active from about September 10 to November 20, whereas the North Taurids are active from about October 20 to December 10.
Peak dates aside, meteor aficionados will be on the lookout as the South and North Taurids simultaneously produce meteors in late October and early November. Higher rates of Taurid fireballs might happen in seven-year cycles, and the last grand fireball display was in 2015.
In short, the Taurid meteors might produce a “swarm” of fireballs in late October and early November, regardless of which date the South Taurid meteor shower peaks!
Bottom line: It’s meteor season! This shower rarely produces more than 5 meteors per hour (although it’s been known to produce fireballs). Now … when do the South Taurids peak, October or November?
Bruce McClure has served as lead writer for EarthSky's popular Tonight pages since 2004. He's a sundial aficionado, whose love for the heavens has taken him to Lake Titicaca in Bolivia and sailing in the North Atlantic, where he earned his celestial navigation certificate through the School of Ocean Sailing and Navigation. He also writes and hosts public astronomy programs and planetarium programs in and around his home in upstate New York.