LEARN ABOUT

METEOR SHOWERS

A meteor shower is a celestial event in which a number of meteors are observed to radiate, or originate, from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller than a grain of sand, so almost all of them disintegrate and never hit the Earth's surface. Intense or unusual meteor showers are known as meteor outbursts and meteor storms, which may produce greater than 1000 meteors an hour. The Meteor Data Centre lists about 600 suspected meteor showers of which about 100 are well established. Several organizations provide viewing opportunities on the Internet.

LIST OF METEOR SHOWERS IN 2021

Quadrantids

Active from December 28th 2020 to January 12th , 2021

The Quadrantids (QUA) are a January meteor shower. The zenithal hourly rate (ZHR) of this shower can be as high as that of two other reliably rich meteor showers, the Perseids in August and the Geminids in December, yet Quadrantid meteors are not seen as often as meteors in these other two showers, because the peak intensity is exceedingly sharp, sometimes lasting only hours. Additionally, the meteors are quite faint (mean magnitude 3-6 mag).

The radiant point of this shower is at the northern edge of the constellation Boötes, not far from the Big Dipper. It lies between the end of the handle of the Big Dipper and the quadrilateral of stars marking the head of the constellation Draco. This meteor shower is best seen in the northern hemisphere, but it can be seen partly to 50 degrees south latitude.

• Peaks on the 3rd of January
   

Lyrids

Active from April 14th to April 30th , 2021

The April Lyrids (LYR, IAU shower number 6 ) are a meteor shower lasting from April 14 to April 30th. The radiant of the meteor shower is located in the constellation Lyra, near this constellation's brightest star, Alpha Lyrae (proper name Vega).

The source of the meteor shower is particles of dust shed by the long-period Comet C/1861 G1 Thatcher. The April Lyrids are the strongest annual shower of meteors from debris of a long-period comet, mainly because as far as other intermediate long-period comets go (200–10,000 years), this one has a relatively short orbital period of about 415 years. The Lyrids have been observed and reported since 687 BC; no other modern shower has been recorded as far back in time.

Counts typically range from 5 to 20 meteors per hour, averaging around 10. As a result of light pollution, observers in rural areas will see more than observers in a city. Nights without a moon in the sky will reveal the most meteors. April Lyrid meteors are usually around magnitude +2. However, some meteors can be brighter, known as "Lyrid fireballs", cast shadows for a split second and leave behind smokey debris trails that last minutes.

• Peaks on the 22nd of April
   

Eta Aquariids

Active from April 19th to May 28th , 2021

The Eta Aquariids are a meteor shower associated with Halley's Comet.

Unlike most major annual meteor showers, there is no sharp peak for this shower, but rather a plateau of good rates that last approximately one week centered on May 7. The meteors we currently see as members of the Eta Aquariid shower separated from Halley’s Comet hundreds of years ago. The current orbit of Halley’s Comet does not pass close enough to the Earth to be a source of meteoric activity.

Although this shower is not as spectacular as the Leonids, it is not an ordinary event. The Eta Aquariids get their name because their radiant appears to lie in the constellation Aquarius, near one of the constellation's brightest stars, Eta Aquarii. The shower peaks at about a rate of around a meteor per minute, although such rates are rarely seen from northern latitudes due to the low altitude of the radiant.

The Eta Aquariids are best viewed in the pre-dawn hours away from the glow of city lights. For northern observers, the radiant of the shower is only above the horizon for the few hours before dawn, and early-rising observers are often rewarded with rates that climb as the radiant rises before sunrise. The shower is best viewed from the equator to 30 degrees south latitude.

• Peaks on the 5th of May

Southern Delta Aquariids

Active from July 12th to August 23rd , 2021

The Southern Delta Aquariids are a meteor shower visible from mid July to mid August each year. The shower originated from the breakup of what are now the Marsden and Kracht Sungrazing comets.

The Delta Aquariids get their name because their radiant appears to lie in the constellation Aquarius, near one of the constellation's brightest stars, Delta Aquarii. The name derives from the Latin possessive form "Aquarii". There are two branches of the Delta Aquariid meteor shower, Southern and Northern. The Southern Delta Aquariids are considered a strong shower, with an average meteor observation rate of 15–20 per hour, and a peak zenith hourly rate of 18. The average radiant is at RA=339°, DEC=−17°.

The Northern Delta Aquariids are a weaker shower, peaking later in mid August, with an average peak rate of 10 meteors per hour.

• Peaks on the 30th of July
   

Alpha Capricornids

Active from July 3rd to August 15th , 2021

The meteor shower was discovered by Hungarian astronomer Miklos von Konkoly-Thege in 1871.This shower has infrequent but relatively bright meteors, with some fireballs. Parent body is comet 169P/NEAT.

Peter Jenniskens and Jeremie Vaubaillon identified the parent body as asteroid 2002 EX12, which in the return of 2005 was found weakly active near perihelion. This object is now called comet 169P/NEAT.

According to Jenniskens and Vaubaillon, the meteor shower was created about 3,500 to 5,000 years ago, when about half of the parent body disintegrated and fell into dust. The dust cloud evolved into Earth's orbit recently, causing a shower with peak rates of 2-5/h, sometimes having outbursts of bright flaring meteors with rates up to 5-9/h.

The bulk of the dust will not be in Earth's path until the 24th century. The Alpha Capricornids are expected to become a major annual storm in 2220–2420 A.D., one that will be "stronger than any current annual shower."

• Peaks on the 30th of July
   

Perseids

Active from July 17th to August 24th , 2021

The stream of debris is called the Perseid cloud and stretches along the orbit of the comet Swift–Tuttle. The cloud consists of particles ejected by the comet as it travels on its 133-year orbit. Most of the particles have been part of the cloud for around a thousand years. However, there is also a relatively young filament of dust in the stream that was pulled off the comet in 1865, which can give an early mini-peak the day before the maximum shower. The dimensions of the cloud in the vicinity of the Earth are estimated to be approximately 0.1 astronomical units (AU) across and 0.8 AU along the latter’s orbit, spread out by annual interactions with the Earth’s gravity.

Depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour. They can be seen all across the sky; however, because of the shower’s radiant in the constellation of Perseus, the Perseids are primarily visible in the Northern Hemisphere. As with many meteor showers the visible rate is greatest in the pre-dawn hours, since more meteoroids are scooped up by the side of the Earth moving forward into the stream, corresponding to local times between midnight and noon, as can be seen in the accompanying diagram. While many meteors arrive between dawn and noon, they are usually not visible due to daylight. Some can also be seen before midnight, often grazing the Earth’s atmosphere to produce long bright trails and sometimes fireballs. Most Perseids burn up in the atmosphere while at heights above 80 kilometres (50 mi).

• Peaks on the 12th of August

Southern Taurids

Active from September 10th to November 20th , 2021

The Taurids are an annual meteor shower, associated with the comet Encke. The Taurids are actually two separate showers, with a Southern and a Northern component. The Southern Taurids originated from Comet Encke, while the Northern Taurids originated from the asteroid 2004 TG10. They are named after their radiant point in the constellation Taurus, where they are seen to come from in the sky. Because of their occurrence in late October and early November, they are also called Halloween fireballs.

Encke and the Taurids are believed to be remnants of a much larger comet, which has disintegrated over the past 20,000 to 30,000 years, breaking into several pieces and releasing material by normal cometary activity or perhaps occasionally by close encounters with the tidal force of Earth or other planets (Whipple, 1940; Klačka, 1999). In total, this stream of matter is the largest in the inner solar system. Since the meteor stream is rather spread out in space, Earth takes several weeks to pass through it, causing an extended period of meteor activity, compared with the much smaller periods of activity in other showers. The Taurids are also made up of weightier material, pebbles instead of dust grains.

• Peaks on the 10th of October

Orionids

Active from October 2nd to November 7th , 2021

The radiant of the Orionids is located between the constellations Orion and Gemini (in the south-eastern sky before dawn, as viewed from mid-northern latitudes.

Universe Today reported that the meteor shower arrived at 140,000 miles (230,000 km) per hour on the morning of the 21 when showing was predicted to be at its height, however compared to previous showers in years past, the trail of 2009 appeared narrower without branching out. Observers observing the small meteor "Halleyids" at Alabama's Space Flight Center saw streaks radiating in all directions with the naked eye.

• Peaks on the 21st of October

Northern Taurids

Active from October 20th to December 10th , 2021

The Taurids are an annual meteor shower, associated with the comet Encke. The Taurids are actually two separate showers, with a Southern and a Northern component. The Southern Taurids originated from Comet Encke, while the Northern Taurids originated from the asteroid 2004 TG10. They are named after their radiant point in the constellation Taurus, where they are seen to come from in the sky. Because of their occurrence in late October and early November, they are also called Halloween fireballs.

Encke and the Taurids are believed to be remnants of a much larger comet, which has disintegrated over the past 20,000 to 30,000 years, breaking into several pieces and releasing material by normal cometary activity or perhaps occasionally by close encounters with the tidal force of Earth or other planets (Whipple, 1940; Klačka, 1999). In total, this stream of matter is the largest in the inner solar system. Since the meteor stream is rather spread out in space, Earth takes several weeks to pass through it, causing an extended period of meteor activity, compared with the much smaller periods of activity in other showers. The Taurids are also made up of weightier material, pebbles instead of dust grains.

• Peaks on the 12th of November

Leonids

Active from November 6th to November 30th , 2021

The Leonids are a prolific meteor shower associated with the comet Tempel –Tuttle. 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. They peak in the month of November.

Earth moves through the meteoroid stream of particles left from the passages of a comet. The stream comprises solid particles, known as meteoroids, ejected by the comet as its frozen gases evaporate under the heat of the Sun when it is close enough – typically closer than Jupiter's orbit. 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 bright (apparent magnitude −1.5) meteors. An annual Leonid shower may deposit 12 or 13 tons of particles across the entire planet.

The meteoroids left by the comet are organized in trails in orbits similar to though different from that of the comet. They are differentially disturbed by the planets, in particular Jupiter and to a lesser extent by radiation pressure from the sun, the Poynting–Robertson effect, and the Yarkovsky effect. These trails of meteoroids cause meteor showers when Earth encounters them. Old trails are spatially not dense and compose the meteor shower with a few meteors per minute. In the case of the Leonids, that tends to peak around November 18, but some are spread through several days on either side and the specific peak changes every year. Conversely, young trails are spatially very dense and the cause of meteor outbursts when the Earth enters one. Meteor storms (large outbursts) exceed 1000 meteors per hour, to be compared to the sporadic background (5 to 8 meteors per hour) and the shower background (several per hour).

• Peaks on the 17th of November
   

Geminids

Active from December 4th to December 20th , 2021

The Geminids are a meteor shower caused by the object 3200 Phaethon, which is thought to be a Palladian asteroid with a "rock comet" orbit. This would make the Geminids, together with the Quadrantids, the only major meteor showers not originating from a comet. The meteors from this shower are slow moving, can be seen in December and usually peak around mid December , with the date of highest intensity being the morning of the peak. The shower is thought to be intensifying every year and recent showers have seen 120–160 meteors per hour under optimal conditions, generally around 02:00 to 03:00 local time. Geminids were first observed in 1862, much more recently than other showers such as the Perseids (36 AD) and Leonids (902 AD).

The meteors in this shower appear to come from a radiant in the constellation Gemini (hence the shower's name). However, they can appear almost anywhere in the night sky, and often appear yellowish in hue. Well north of the equator, the radiant rises about sunset, reaching a usable elevation from the local evening hours onwards. In the southern hemisphere, the radiant appears only around local midnight or so. Observers in the northern hemisphere will see higher Geminid rates as the radiant is higher in the sky. The meteors travel at medium speed in relation to other showers, at about 22 miles per second (35 km/s), making them fairly easy to spot. The Geminids are now considered by many to be the most consistent and active annual shower. Geminids disintegrate while at heights above 24 miles (39 km).

• Peaks on the 14th of December
    

Ursids

Active from December 17th to December 26th , 2018

The Ursids (URS) meteor activity begins annually around December 17 and runs for a week plus, until the 25th or 26th. This meteor shower is named for its radiant point which is located near the star Beta Ursae Minoris in the constellation Ursa Minor.

Ursid shower delivers only a modest 10 meteors per hour under even the best conditions, it has the advantage of having a radiant near the bowl of the Little Dipper — so it's in view all night from northern latitudes.

• Peaks on the 22nd of December
   

THE CHELYABINSK METEOR IN RUSSIA FEBRUARY 2013

Chelyabinsk meteor. The Chelyabinsk meteor was a superbolide caused by an approximately 20-metre near-Earth asteroid that entered Earth's atmosphere over Russia on 15 February 2013 at about 09:20 YEKT (03:20 UTC), with a speed of 19.16 ± 0.15 kilometres per second (60,000–69,000 km/h or 40,000–42,900 mph).

It quickly became a brilliant superbolide meteor over the southern Ural region. The light from the meteor was brighter than the Sun, visible up to 100 km (62 mi) away. It was observed over a wide area of the region and in neighboring republics. Some eyewitnesses also felt intense heat from the fireball.

Due to its high velocity and shallow angle of atmospheric entry, the object exploded in an air burst over Chelyabinsk Oblast, at a height of around 29.7 km (18.5 mi; 97,000 ft). The explosion generated a bright flash, producing a hot cloud of dust and gas that penetrated to 26.2 km (16.3 mi), and many surviving small fragmentary meteorites, as well as a large shock wave. The bulk of the object's energy was absorbed by the atmosphere, with a total kinetic energy before atmospheric impact estimated from infrasound and seismic measurements to be equivalent to the blast yield of 400–500 kilotons of TNT (about 1.4–1.8 PJ) range – 26 to 33 times as much energy as that released from the atomic bomb detonated at Hiroshima.

The object was undetected before its atmospheric entry, in part because its radiant was close to the Sun. Its explosion created panic among local residents, and about 1,500 people were injured seriously enough to seek medical treatment. All of the injuries were due to indirect effects rather than the meteor itself, mainly from broken glass from windows that were blown in when the shock wave arrived, minutes after the superbolide's flash. Some 7,200 buildings in six cities across the region were damaged by the explosion's shock wave, and authorities scrambled to help repair the structures in sub-freezing temperatures.

With an estimated initial mass of about 12,000–13,000 metric tons (13,000–14,000 short tons, heavier than the Eiffel Tower), and measuring about 20 metres in diameter, it is the largest known natural object to have entered Earth's atmosphere since the 1908 Tunguska event, which destroyed a wide, remote, forested, and very sparsely populated area of Siberia. The Chelyabinsk meteor is also the only meteor confirmed to have resulted in a large number of injuries. No deaths were reported.

The earlier-predicted and well-publicized close approach of a larger asteroid on the same day, the roughly 30-metre 367943 Duende, occurred about 16 hours later; the very different orbits of the two objects showed they were unrelated to each other.

LOCALS REPORT FROM THAT DAY

Local residents witnessed extremely bright burning objects in the sky in Chelyabinsk, Kurgan, Sverdlovsk, Tyumen, and Orenburg Oblasts, the Republic of Bashkortostan, and in neighbouring regions in Kazakhstan, when the asteroid entered the Earth's atmosphere over Russia. Amateur videos showed a fireball streaking across the sky and a loud boom several minutes afterwards. Some eyewitnesses also felt intense heat from the fireball.
 

The event began at 09:20:21 Yekaterinburg time, several minutes after sunrise in Chelyabinsk, and minutes before sunrise in Yekaterinburg. According to eyewitnesses, the bolide appeared brighter than the sun, as was later confirmed by NASA.An image of the object was also taken shortly after it entered the atmosphere by the weather satellite Meteosat 9. Witnesses in Chelyabinsk said that the air of the city smelled like "gunpowder", "sulfur" and "burning odors" starting about 1 hour after the fireball and lasting all day.