Another cool shot of a Taurid fireball, posted on November 11, 2015, at EarthSky Photos on G+ by Bill Allen. Thanks, Bill! By all reports, this shower has been amazing in 2015.
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 hours 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 9-10 whereas the American Meteor Society (AMS) gives the night of October 28-29, claiming that this shower “rarely produces more than five shower members per hour, even at maximum activity.”
Guy Ottewell, in his 2012 Astronomical Calendar, helps to explain the discrepancy for the peak date of the South Taurid meteor shower. He explains, “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.
The Taurid meteors consist of two streams, the South Taurid and North Taurid meteors. Both streams appear to originate from the constellation Taurus the Bull.
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. Depending on the source, the South Taurid peak comes in October or early November.
View larger South Taurid meteor. Note the Pleiades star cluster above the meteor, and the bright star Aldebaran roughly midway between the Pleiades and the meteor. Image via Flickr user Rocy Raybell
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!
from EarthSky https://ift.tt/2PoqI3U
Another cool shot of a Taurid fireball, posted on November 11, 2015, at EarthSky Photos on G+ by Bill Allen. Thanks, Bill! By all reports, this shower has been amazing in 2015.
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 hours 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 9-10 whereas the American Meteor Society (AMS) gives the night of October 28-29, claiming that this shower “rarely produces more than five shower members per hour, even at maximum activity.”
Guy Ottewell, in his 2012 Astronomical Calendar, helps to explain the discrepancy for the peak date of the South Taurid meteor shower. He explains, “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.
The Taurid meteors consist of two streams, the South Taurid and North Taurid meteors. Both streams appear to originate from the constellation Taurus the Bull.
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. Depending on the source, the South Taurid peak comes in October or early November.
View larger South Taurid meteor. Note the Pleiades star cluster above the meteor, and the bright star Aldebaran roughly midway between the Pleiades and the meteor. Image via Flickr user Rocy Raybell
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!
from EarthSky https://ift.tt/2PoqI3U
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