ATLANTIC SKY: Look up! The Orionids meteor shower – descendant of Comet Halley – will be visible soon | SaltWire

One of fall’s most reliable meteor showers — the Orionids — peaks during the nighttime of October 20-21.

The shower’s radiant (the apparent point in the night sky from which the meteors appear to originate) lies in the constellation of Orion – the hunter, directly above the mace he holds above him.

This large constellation (26th of the 88 established constellations) is one of the most easily recognized and conspicuous constellations in the autumn and winter night skies. It takes its name from ancient Greek mythology about the famous hero and hunter Orion.

The son of Poseidon, the Greek god of the sea, and Euryale, the daughter of King Minos of Crete, Orion was known for his great strength, talent for hunting, and many adventures. One such adventure included his love and pursuit of the “Seven Sisters” (the open star cluster of the Pleiades, upper right of Orion and Taurus), daughters of Atlas (the Titan condemned by Zeus to carry the heavens on his shoulders). support for eternity) and the oceanic nymph Pleione. Another concerned an insult to Artemis, the Greek goddess of the hunt, who sent a giant scorpion (later placed by the gods in the night sky as the constellation Scorpius – the scorpion) to kill Orion.

This constellation was also well known to many ancient cultures. The ancient Sumerians associated the Orion constellation with their legendary hero, Gilgamesh, also a man of great strength who fought a huge bull represented by the Taurus constellation – the Taurus (upper right in Orion).

The ancient Babylonians gave Orion the name Mulsipazianna, meaning “The Heavenly Shepherd.” To the ancient Egyptians he was Osiris – god of the dead and resurrection. To the Aztecs, Orion’s three belt stars and sword stars were called “The Exercise of Fire,” the appearance of which signaled the beginning of their New Fire Ceremony, held each year to delay the coming of the end of the world.

In Australia these same stars are sometimes referred to as “The Pot” or “The Saucepan”, while in South Africa these stars are known as “Drie Konings” (The Three Kings) or “Drie Susters” (The Three Sisters). , and in Spain and Latin America as “Las Tres Marias” (The Three Marys).

Halley’s Comet

The Orionids are one of two meteor showers associated with the famous Comet Halley (1P/Halley); the second shower was the Eta Aquarids in May.

This comet is known throughout history, with records going back to at least 240 BC. dating back. It was “discovered” by the English astronomer Edmund Halley (1656-1742), who correctly predicted its return in either 1758 or 1759, based on his studies of three comets that had appeared in 1531, 1607 and 1682.

Halley was the first astronomer to understand that these apparitions were actually the reappearance of the same comet. His prediction proved correct when the comet reappeared in the night sky on Christmas Eve 1758. Unfortunately, Halley was already deceased by that time, but for his insight, the comet was named after him posthumously.

Comet Halley is what is known as a short-period comet – a comet with an orbital period of less than 200 years – or that has been observed during more than one perihelion (closest approach to the Sun).

It is also the only known short-period comet that is regularly visible to the naked eye.

With an orbital period of 76 to 79 years (the delayed return is due to gravitational influences from Jupiter and Saturn), Comet Halley, last seen in 1986, will not revisit our solar system until 2061. Unfortunately, although I saw the 1986 apparition (I was 39 at the time), I will not see it again.

Events:

• 17 Oct – Moon in last quarter
• -Moon at apogee (furthest from Earth)
• 20-21 Oct. – Orionid meteor shower; over night

Harbingers of Doom?

Comets were often seen as a sign of doom and disaster. While this notion is incorrect, there have been a number of events throughout history when the comet was in the sky (or had just passed) that seemed to support this idea, at least to the uneducated.

An example was the comet’s appearance in 1066 when the Anglo-Saxon King Harold was killed by the Norman King William, allowing William to claim the English throne and irrevocably change English history and culture.

It is also said that the comet’s appearance in 1222 encouraged the great Mongol leader Genghis Khan to invade Europe.

When Halley’s Comet appeared in the sky in 1910, it contributed to the unrest in China caused by the Xinhai Revolution, which overthrew the Qing Dynasty, the last orthodoxy in Chinese history, in 1911.

What are the Orionids?

Visible in the night sky from about September 26 to November 22, the Orionids were first discovered in 1839.

Considered one of the most beautiful meteor showers of the year, the Orionids impact the Earth’s upper atmosphere at more than 15,000 miles per hour (about 67 meters/second), producing very bright meteors that often leave smoke plumes for several seconds.

The shower’s radiant will rise above the southeastern horizon at around 10:30 p.m. and will reach its highest point in the sky at around 4 a.m., just as the waning crescent moon is rising.

Expect anywhere from 20 to more than 40 meteors per hour during the peak pre-dawn period from a dark location away from city lights. As with all meteor showers, numbers vary from year to year, sometimes with a surprising number of meteors appearing in any given year.

Weather permitting, take a moment to drive out of the city or where you live and watch for a few minutes for a glimpse of Comet Halley’s luminous descendants.

This week’s sky

• Saturn (magnitude +0.6, in Capricorn – the sea goat) becomes accessible around 6:15 p.m., 22 degrees above the southeastern horizon, reaches a height of 27 degrees above the southern horizon just before 9 p.m. and remains until about 12:00 p.m Clock observable: 30 a.m. when it drops below 10 degrees above the southwestern horizon.
• Bright Jupiter (magnitude -2.9, in Pisces – the Pisces) is visible around 18:40 10 degrees above the east-southeast horizon, reaches 42 degrees above the southern horizon around 23:30 and will remain until about 4 April :00 a.m. visible: 40 a.m. when it falls below seven degrees above the western horizon.
• Mars (magnitude -0.8, in Taurus – the Taurus) becomes accessible when it reaches eight degrees above the east-northeast horizon at approximately 10:30 p.m.; peaking at 66 degrees above the southern horizon at 5 a.m. before losing 55 degrees above the southwestern horizon at dawn twilight just after 7 a.m
• Mercury (magnitude -0.9, in Virgo – the Virgo), now moving toward Sun conjunction, appears just before dawn, rising in the east at about 6:30 am and reaching just 10 degrees above the horizon before it as Mars fades. into dawn just after 7 a.m
• Venus, also approaching solar conjunction, is too close to the Sun to be observed.

Clear skies until next week.

Glenn K. Roberts lives in Stratford, PEI and has been an avid amateur astronomer since childhood. He welcomes comments from readers at [email protected]