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If the skies are clear during the next week, be sure to take a few minutes to gaze upwards. You may be lucky and catch a glimpse of an extraordinarily bright meteor – a taurid meteor.
While most meteor showers are remarkably active for about a week, the Taurids have perhaps the longest duration of overall visibility. Meteors from this particular stream begin appearing in our night sky around October 21 and will continue until around November 27. November 5 to November 12 is traditionally the time period when these slow, majestic meteors are at their best.
Unfortunately, in 2020, this visualization has – so far – been severely hampered by the presence of a bright moon. The moon filled up on Halloween night (the so-called “Blue Moon”). That night, brilliant moonlight flooded the sky for much of the night and drowned out all but the brightest meteors. From then on, however, the moon set later in the evening and slowly dimmed. The last quarter arrives on Sunday 8 November and from then on the moon will be a gradually thinning crescent moon.
Related: How meteor showers work (infographic)
Moonrise on November 5th comes around 8:30 pm local time. But with each passing night, the moon will rise on average about 68 minutes later, and the dark sky hours window (before moonrise) will open a little wider. The nighttime hours from November 11 to November 12 morning hours are probably the best night to watch the Taurid meteor shower, as the moon – now a thin waning crescent – won’t rise until about 3:15 am, leaving about 9 am. hours of dark and moonless skies for those looking for the Taurids.
Every evening, until the moment the moon rises above the horizon, 10 to 15 meteors can appear per hour. They are often yellow-orange and, as the meteors pass, appear to move rather slowly. Their name comes from the way they appear to radiate from the constellation of Taurus, the Taurus, which is located in the lower east a couple of hours after sunset and is almost directly overhead around 1:30.
Astrophotographer Jeff Berkes took this photo of a bull meteor from Assateague Island National Seashore along Maryland’s eastern shores on November 5, 2016. (Image credit: Jeff Berkes Photography)
Meteors – commonly called “shooting stars” – are generated when debris enters and burns in the Earth’s atmosphere. In the case of the Taurids, they are attributed to debris left by Encke’s comet, or perhaps by a much larger comet which, disintegrating, left Encke and many other debris in its wake.
And indeed, the taurid debris stream contains considerably larger fragments than those released by other comets, which is why this meteor stream occasionally releases some unusually bright meteors known as “fireballs.” Encke has the shortest known orbital period for a comet, taking only 3.3 years to make a complete trip around the sun.
Related: How comets cause meteor showers
Two streams for the price of one
Taurids are actually divided into Northern Taurids and Southern Taurids. This is an example of what happens to a meteor stream as it ages. Even in the beginning, the particles could not have moved in exactly the same orbit as their mother comet; their slight divergence builds up over time.
The sun is not the only body that gravitationally controls the orbits of particles; the planets are having their subtle effects on the current. As the positions of the planets constantly change, particles pass closer to them in some revolutions than in others, diverting parts of the flow, fanning it and dividing it. Thus, what was originally a flow spreads out into a cloud of minor currents and isolated particles in individual orbits, traversing the Earth’s orbit at even more widespread times of the year and coming from more scattered directions until they are completely mixed. in the general dust haze in the solar system.
The two radians, or points where meteors appear to originate in the sky, lie just south of the Pleiades star cluster. So, over the next couple of weeks, if you see a bright, slightly colored orange meteor gliding rather lazily out of that famous little patch of stars, you can be sure it was probably a Tauris.
A swarm of comet fragments
Dr Victor Clube, an English astrophysicist and expert on comets and cosmology, suggested in a 1991 paper that the Taurid meteor stream contains perhaps half a dozen life-sized asteroids whose orbits place them exactly in the stream. Clube and his colleagues say the Taurid’s range of orbits indicate that they were all released by a huge comet, originally 100 miles (160 kilometers) in diameter or more, that entered the inner solar system about 20,000 years ago. 10,000 years ago it was dry and brittle; Encke’s Comet may actually be the largest remaining chunk.
Some astronomers believe that another branch of the Taurid swarm – one with which the Earth interacts
with another part of our orbit, in June, it may have given rise to the famous Tunguska
meteoric event over northeastern Siberia in 1908.
Encke has the shortest known orbital period for a comet, taking only 3.3 years to make a complete trip around the sun. Meteorite expert David Asher put forward a theory of a “resonant meteor shower” within the Tauride Complex. In short, it predicts that in specific years, the Earth will be hit by more (than average years) meteoroids capable of producing taurid fireballs.
According to Asher, the next “swarm year” is in 2022. But in a moment of bad timing, the moon will become full on November 8, right in the middle of the “privileged observation period” for that year.
Joe Rao is an instructor and guest lecturer at Hayden Planetarium in New York. He writes about astronomy for Natural History magazine, the Farmers’ Almanac and other publications. Follow us on Twitter @Spacedotcom and on Facebook.
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