In mid-November, spectacular meteors will streak through the night sky as the Leonid meteor shower hits Earth once again. This annual meteor shower is responsible for some of the most intense meteor storms in history. The 1966 Leonids were certainly the greatest meteor shower in recorded history as it produced rates as high as 40 meteors per SECOND! We celebrate this year the 50th anniversary of this unforgettable event.
The Leonids are associated with the comet Tempel–Tuttle (55P). Earth moves through the meteoroid stream of particles left from the passages of this comet every year in November. The Leonids are a fast moving stream which encounter the path of Earth and impact at 72 km/s. Larger Leonids which are about 10 mm across have a mass of half a gram and are known for generating very bright meteors. An annual Leonid shower may deposit 12 or 13 tons of particles across the entire planet. The Leonids get their name from the location of their radiant in the constellation Leo: the meteors appear to radiate from that point in the sky.
The Leonids had been relatively quiet for 100 years between 1866 and 1966. Astronomers predicted an intense display in 1899 and when they failed to impress that year the public scorned astronomers for many years. It was not until the bright comets of 1910 did the public look again favorably on astronomers.
The sky was raining meteors
In Journal of the British Astronomical Association, Vol. 77, pp.89-93, Denis Milon, Association of Lunar and Planetary Observers remembers:
James W. Young was one of the few people who photographed this event. Young observed the shower from the Table Mountain Observatory, operated by the Jet Propulsion Laboratory (JPL), located just west of the town of Wrightwood, California at an elevation of 7500 feet. Young says:
Alan Duniven witnessed the storm from Texas:
Panhandle, near McLean. We apparently came out at about the peak time as approximately 50 meteors per second were radiating from one area of the sky at a very high angle. It appeared much like a sparkler from the 4th of July except there was a small vacant hole from which they radiated out.
In “Leonid predictions for the period 2001-2100“, WGN, Journal of the International Meteor Organization, 35 (1): 5–12, Mikhail Maslov explains that a number of outbursts are expected in 2034 and 2035. It will be quite strong, and considering the proximity of comet Tempel–Tuttle, activity at 18:00UT on November 17th should reach a ZHR (the rate a meteor shower would produce if seen by an observer with a clear, dark sky, and with the radiant at the zenith) of 40-50 meteors. Maslov predicts a ZHR of 150-250 meteors on november 18th this year and a ZHR of 300-400 meteors on november 19th. For comparison, the ZHR for this year and next year should be around 10…