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Comet Encke and TauridMeteorites


1999 Beta Taurid Meteorites:

7 July 1999 -Giant meteor explodes over New Zealand

According to an 8 July 1999 article in the LondonTelegraph by Paul Chapman,

"... A SEARCH began yesterday for the remains of a large meteorthat exploded over New Zealand's North Island with enough force toshake buildings, leaving a plume of blue smoke

(photo from the New ZealandHerald, according to which "... The Carter Observatory inWellington received reports of the meteorite about 4.15 pm. It waspicked up by aircraft and radar. ...".)

that covered hundreds of square miles. Falling debris from themeteor, which eyewitnesses said was as bright as the sun, was blamedfor starting a forest fire near Napier, on the east coast. Thespectacular explosion was seen by people on both sides of the NorthIsland and from as far north as Auckland to Christchurch in the SouthIsland. Witnesses said the fireball had a long, fiery tail. Airlinepilots reported sightings and the meteor was picked up on radar byair-traffic controllers. Rodney Austin, information officer for theNew Zealand Astronomical Society, said the meteor could have been aslarge as a railway locomotive. One scientist said it could provedifficult to find in New Zealand's rugged and sparsely populatedlandscape. ...".

 

1998 Beta Taurid Meteorites:

20 June 1998 - According to the 3 July 1998 edition of Skyand Telescope's Weekly News Bulletin, a meteorite fell about 100kilometers from Tashauz, Turkmenistan. The daylight fall was precededby a dazzling orange bolide that left a train of black smoke as itmoved northeast across the sky. The projectile broke into at leastthree pieces before impact, and the largest fragment created a smallcrater about 6 meters wide and 4 deep. At its bottom a recovery teamfound a cone-shaped stony iron meteorite weighing between 300 and 500kilograms.

13 June 1998 - Meteorites fell in Nashville,Tennessee, and in Portales, New Mexico, according to Skyand Telescope's Weekly News Bulletin of 19 June 1998.

 


COMET ENCKE:

 In 1940 Whipple discovered that the Taurid meteors were fragments of Comet Encke, with period 3.3 years, perihelion 0.34 AU, and aphelion 4.1 AU, and that the differences in the orbits of the meteors and Comet Encke looked like the result of 14,000 years of perturbations by Jupiter.   In 1950, Whipple and Hamid discovered that the orbits of four Taurid meteors coincided with the orbit of Comet Encke as of 4700 years ago, and that, as of 1500 years ago, the orbits of three other Taurid meteors coincided with each other but not with the orbit of Comet Encke.  They concluded that the latter three Taurids were formed by a breakup 1500 years ago of a fragment that had in turn broken off from Comet Encke much earlier.   

According to the webpage of Gary Kronk, Whipple's 1940 paper discussed more than theTaurids and their link to comet Encke. Whipple said the stream'sapparent spread of 0.2 AU meant Mercury, Venus and Mars were alsolikely to encounter it.

 

Clube says that fragments of Comet Encke make up the Taurid meteor stream, which peaks around 30 June in daylight hours but is visible in the night skies of November, and that the Earth passes through each dense part of this belt of debris every 3000 years.  

The daylight June Taurids, known as the Beta Taurids, are activeduring June 5 to July 18 with a relatively flat maximum centered onJune 29, according to the webpage of Gary Kronk.

The nighttime Taurids fall into two streams, the Northern (activefrom October 12 to December 2 with maximum during November 4-7) andSouthern (active from September 17 to November 27 with maximum duringOctober 30 to November 7. The Northern Taurids have orbits that arevery similar to the daylight Beta Taurids. (See the webpage of Gary Kronk.)

 Given the incompleteness and uncertainties of observations, and uncertainties of calculations, and the rough estimate nature of the scales of time, etc., that I use on my WWW pages, I take the size of the parent comet to be roughly 100 km, roughly the size of Hale-Bopp or Sarabat, and the initial breakup of Comet Encke to be about 12,000 years ago, roughly coincident with the Vela X Supernova and with the end of the Ice Age, and secondary breakups to have occurred about 4,500 years ago and about 1,500 years ago.   Observers on Earth see the Taurids as appearing to come from a radiant point in Taurus near the Pleiades.   12,000 years ago, when the Ice Age ended, they might have seen a spectacular cometary display near the Pleiades, as the Earth could have encountered a lot of comet dust that might have affected its climate, all with the Vela X supernova appearing in the south.   In his book Rogue Asteroids and Doomsday Comets (John Wiley, 1995),Duncan Steel says a majority view of the consequences to Earth of major comet/meteor impact is that:        1 - for weeks, radiated heat (and impact heat) would heat up          the Earth, causing global fires, which in turn would          put a lot of soot and CO2 into the atmosphere;       2 - for years, atmospheric soot, dust, and pulverized rock would          reflect sunlight, causing a Cosmic Winter.       3 - for thousands of years, atmospheric CO2 would heat the Earth          through the greenhouse effect.   9,000 years ago, after one 3,000 year period, and after 3000 years of greenhouse effect, the Earth entered a 3,000 year period of good climate.   Then there might have been another encounter.   6,000 years ago, when the good climate ended, perhaps due to a severe encounter with the 3000 year periodicity.  There may have been a thousand years or so of greenhouse effect before the Earth's climate stabilized at the beginning of recorded human history about 5,000 years ago.   3,000 years ago, when  the Iron Age began, the Zhou defeated the Shang in China, the short-lived monotheistic reign of Akhenaton ended in Egypt, and Moses led the Israelites out of Egypt,the Chinese recorded that a comet (perhaps this comet) appeared.   The Tunguska Impact of 30 June 1908 may have been due to an Encke fragment associated with the Beta Taurid meteors.  Now Comet Hale-Bopp is appearing, with a 3,000 year period (give or take 1,000 years or so).   For more discussion of possible historical references to the fragments of Comet Encke, see the WWW pages of ABOB's Page.   

 

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