Comets

“Comets are long-haired stars with flames, appearing suddenly, and presaging a change in sovereignty, or plague, or war, or winds or floods.”
Northumberland Bede, De Natura Rerum c. 725AD

Ancient Beliefs

The word comet comes from the Greek word kometes which means ‘long hair’.  Our ancestors thought comets were stars with hair trailing behind them.

In ancient times, people thought comets were ‘power rays’ of supernatural beings.  They also thought that comets contained fire because they were so bright in the sky.

Some people believed comets brought curses with them.  They believed that comets caused cattle to give birth to dead calves, princes to die,  natural disasters to occur, and disease and pestilence to spread across the land.  Emperor Nero of Rome had all possible successors to his throne executed in order to save him from the ‘curse of the comet’.

Not all people believed comets were bad omens; some believed they brought good fortune.  Others believed that they carried angels through the heavens.

Not so ancient beliefs …

In 1909 and 1910, the appearance of Halley’s Comet in the skies caused panic in cities around the world. Pedlars did a lot of  business selling ‘anti-comet sickness pills’ and umbrellas to protect people from the effects of the comet.

In March 1997, the members of a cult called ‘Heaven’s Gate’ committed suicide by drinking a cocktail of poisons.  They believed that the coming of comet Hale-Bopp was a sign that it was time for them to shed their Earthly bodies so that their spirits would take flight behind the comet and so be taken to a higher plane of existence.

More about Comet Hysteria can be found here.

Halley’s Comet

The Chinese recorded sightings of Halley’s Comet as far back as 240BC.

The famous Bayeux Tapestry shows Halley’s comet shining brightly in the sky before the Battle of Hastings in 1066.  Some people believed that the comet meant that King Harold of England would lose his throne to Duke William of Normandy in this battle, and he did!

Edmund Halley studied comets and developed a theory that the comets sighted in 1531, 1607 and 1682 were actually the same comet.  He successfully predicted the return of this comet in 1758, but sadly died 16 years before his prediction was proved correct.  Halley’s Comet is next due to return in 2061.

Other Cometary Scientists

In 1577, Tycho Brahe showed that comets travelled far beyond the Moon; prior to this, people believed comets travelled in the Earth’s atmosphere.

Sir Isaac Newton (1642 – 1727) discovered that comets travel in elliptical orbits around the Sun.  He also believed comets were members of the Solar System, like the planets, and that comets could return again and again – he was right!  Comets that are seen quite often, every 100 years or so, come from the Kuiper Belt.  Comets that we only see every few thousand years come from the Oort Cloud.

Meteor Showers

Comets leave a trail of debris behind them as they orbit the Sun.  If this trail crosses the Earth’s orbit, then at that point every year for a long time there will be a meteor shower.

The Perseid meteor shower occurs every year between the 9th and 13th of August as the Earth passes through the debris of the Swift-Tuttle comet.  The Orionid meteor shower occurs in October when the Earth passes through debris left by Halley’s Comet.  The Leonids, around 18th November, result from debris from comet Tempel-Tuttle which visits the inner Solar System every 33 years.

Hale-Bopp

On July 23, 1995, an unusually large and bright comet was seen outside of Jupiter’s orbit by Alan Hale of New Mexico and Thomas Bopp of Arizona. Careful analysis of Hubble Space Telescope images suggested that its intense brightness was due to its exceptionally large size. While the nuclei of most comets are about 1.6 to 3.2 km (1 to 2 miles) across, Hale-Bopp’s was estimated to be 40 km (25 miles) across. It was visible even through bright city skies, and may have been the most viewed comet in recorded history. Comet Hale-Bopp holds the record for the longest period of naked-eye visibility: an astonishing 19 months. It will not appear again for another 2,400 years.

Swift-Tuttle

This comet was first seen in July 1862 by American astronomers Lewis Swift and Horace Tuttle. As Comet Swift-Tuttle moves closer to the Sun every 120 years, it leaves behind a trail of dust debris that provides the ingredients for a spectacular fireworks display seen in July and August. As Earth passes through the remnants of this dust tail, we can see on a clear night the Perseid meteor shower. Comet Swift-Tuttle is noted as the comet some scientists predicted could one day collide with Earth because the two orbits closely intercept each other. The latest calculations show that it will pass a comfortable 24 million km (15 million miles) from Earth on its next trip to the inner Solar System.

Hyakutake

On January 30, 1996, Yuji Hyakutake (pronounced “hyah-koo-tah-kay”), an amateur astronomer from southern Japan, discovered a new comet using a pair of binoculars. In the spring of that year, this small, bright comet with a nucleus of 1.6 to 3.2 km (1 to 2 miles) made a close flyby of Earth — sporting one of the longest tails ever observed. The Hubble Space Telescope studied the nucleus of this comet in great detail. This is not Comet Hyakutake’s first visit to the inner Solar System. Astronomers have calculated its orbit and believe it was here about 8,000 years ago. Its orbit will not bring it near the Sun again for about 14,000 years.

Some interesting websites about comets and myth.

Comet Mythology from Astrononmy-Education.com

Comets, Meteors & Myth: New Evidence for Toppled Civilizations and Biblical TalesThis is an interesting article from space.com.

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