Sprinkle it with space debris and let it move and amazing events occur to light up the clear night skies, such as famous Comets, Fireballs and Shooting Stars. One of these amazing Celestial events involving meteors, meteoroids or meteorites is the celestial event known as ‘The Meteor Shower’. So let’s take a look at one of the better-known meteor showers that radiates from our night sky into the Earth’s atmosphere, and is associated with – the Constellation Leo, the popular ‘Leo the Lion’. We are of course talking about the Leonids meteor shower.
The Leonids Meteor Shower (The Leonids)
The different names
Asteroids, Comets and Meteors are regarded as the leftovers following the formation of our Solar System, some 4.6 billion years ago. They have not changed over time and remain a fossil-like reminder of our planetary evolution.
Before we can describe the facts around meteor showers we need to understand what they are and the difference between a Meteoroid, a Meteor and a Meteorite?
Their similar names can be a little bit confusing, but basically these three names are used to describe the same space object depending on where it is on its journey from Space to Earth.
Each is part of a process that occurs when an object from Space falls to Earth; while in orbit they are called meteoroids, as they travel into the Earth’s atmosphere they are called Meteors and on their closest approach, if they make contact with Earth, they become meteorites:
– Is a small fragment of space rock, or iron, from outer Space (that is either a meteoroid or asteroid, or extinct Comet), which does not disintegrate as it enters the Earth’s atmosphere as a meteor?
When it falls and impacts the surface of the Earth it is called a Meteorite.
Meteorites can be Stony meteorites, Iron meteorites or Stony-iron meteorites.
– Is a meteoroid (a space rock) that has entered the earth’s atmosphere and vaporized into a meteor (or shooting star)
As the meteoroid rapidly travels towards Earth through the Earth’s atmosphere the drag, or resistance, as it passes through the air causes friction making it become very hot.
These bright meteors, or meteor streaks, that light up the night sky as they travel rapidly are what’s known as ‘Shooting Stars’ or ‘Fireballs’.
FACT: Shooting Stars are not Stars they are in fact space debris left behind from the parent body, a parent Comet or a parent Asteroid.
The part of the Shooting Star known as the bright meteor streak or the flaming tail is one of the top sights for Skywatchers.
It is a common image associated with a Shooting Star, although it is not part of the rock itself, in fact it is the glowing hot air left by the hot rock as it travels through the earth’s atmosphere towards our Planet Earth.
When several meteoroids encounter Earth at the same time it is known as a Meteor Shower.
When this meteor finally makes contact with the Earth it’s known as a meteorite.
The ancient names for a Meteor:
- Meteorum – from Latin
- Meteoron – from Ancient Greek
- Metheour – from old English language
- Meteore – from old French Language
The early naming of this astronomical phenomenon involves the combination of the word “meta’ meaning high in the air, and a version of the word ‘aoros’ meaning to lift up.
Ancient civilizations have been seeing meteors for thousands of years.
Some believed the Shooting Stars and Fireballs, in the dark skies, were powerful, and messages of doom, or warnings from their deities (gods).
In the ancient Greek and Roman religions these cultures believed in Helios (Latin name Helius), as the god and personification of the Sun. Any activity involving Helios was feared and respected. It has been depicted over the years in imagery as a horse-drawn chariot racing through the dark sky.
Our inner Solar System
What is happening in the inner solar system where we live?
Within the inner solar system there is much activity and several of the largest objects regularly orbit the Sun.
When a planet like Earth passes the Sun in orbit it is in a fairly circular orbit, however when Comets orbit the Sun the route is often lop-sided.
Not all Planets orbit the Sun, for example Jupiter, which is the largest Planet and has the shortest day in the solar system (of only 10 hours), does not orbit the Sun.
This is confirmed by NASA in its studies using the Juno spacecraft and seen by many scientists using the Earth-orbiting NASA Hubble Space Telescope.
As Comets, or Rock Comets, travel closer to the Sun some of the icy surface melts off and particles of rock and dust are released into orbit. As the Comet continues to travel this space debris is spread along the trail of the Comet littering our inner solar system.
FACT: A Rock Comet is actually an asteroid that travels very close to the Sun and as it does so the solar heating it experiences scorches dusty debris off its rocky surface. Rock Comets can even grow tails from the rocky debris.
Our Planet Earth orbits the Sun several times a year and when its orbit crosses the orbit of a Comet it crashes into the space debris left by Comets, which form Meteoroids.
Meteoroids, like the Leonids Meteoroids, are not the largest objects in Space in fact they are usually small, ranging from a small dust particle up to the size of a boulder. It is unlikely that any will actually strike Earth as they usually burn up in the Earth’s atmosphere first.
The Leonids Meteor Shower– Facts in brief:
What is it? –
The Leonid Meteor showers are named after the Constellation Leo, which is located in the Northern Hemisphere, and have the most spectacular meteor storms every 33 years or so, which are visible by naked eye.
Visible from both the Northern Hemisphere and the Southern Hemisphere, the Leonids meteor shower peaks in November.
Meteor showers originate from a large space object, such as a parent Comet, or an asteroid or even an extinct Comet.
The Leonids originate from the parent Comet 55P, also known as the Comet Tempel-Tuttle. The name suggests they fall like a shower of rain, or storms, but this is not the case.
The Leonids are known for their amazing meteor storms, or outbursts, even reaching over 1,000 per hour, which occur approximately every 33 years.
The meteor showers in the proximity of the Constellation of Leo occur as annual meteor shower, or infrequent meteor storms events and are therefore referred to as the ‘Annual Leonids Meteor Showers’, or ‘The Leonids’ for short.
The earliest record of the Leonids Meteor Storms seen in an earthsky was from around 902 AD.
However the most prolific Leonids meteor storm was reported in 1833 in the area to the East of the Rocky Mountains in North America.
This Leonids meteor storm was far more prolific than those of the Geminids, Orionids or Perseids. It was estimated to last over 9 hours and the spectacular sight was estimated to have its meteors shower peak falling at a rate of over 100,000per hour, up to 240,000 per hour.
It is still possible for sky watchers of the earth sky to see what is considered to be the most prolific meteor shower of all of the annual meteor showers, when viewed, in clear sky, on a dark night in late November.
The Leonids meteor shower peaks annually in mid-November, 17-18.
City lights causing light pollution can negatively impact the visibility of meteor showers and the brightness of a full moon, or even a new moon, can also affect the visibility, throughout the night until early morning.
What’s special about The Leonids Meteor Shower?
There are many factors that distinguish The Leonids from the other named annual meteor showers, such as the Geminids, Orionids or the Perseids.
First find Constellation of Leo, the well-known zodiacal Constellation known as Leo the Lion.
Leo is located in the northern celestial hemisphere between the Constellation of Cancer to the west and the Constellation of Virgo to the east, and lies on the ecliptic like the other zodiac constellations.
FACT: The ecliptic is the path that the Earth takes around the Sun
That’s the best direction in which to see the radiant of the Leonids, one of the major meteor showers. The radiant of the Leonids appears close to the bright Star Gamma Leonis. They originate from this radiant point and they streak in different directions.
These meteor showers are visible from both the Northern Hemisphere and the Southern Hemisphere.
The Leonids Meteor Shower is one of the more spectacular sights in the night sky, resembling falling stars as the travel through the Earth’s upper atmosphere.
FACT: The Earth’s upper atmosphere is a layer of gases held in place by Earth’s gravity. It is a combination of ionized gas, ions and electrons that exist permanently in the atmosphere located around 70km above sea level.
The connection between Shooting Stars and Comets was first made in the 1800s.
The Leonids originate from the parent Comet Tempel-Tuttle’, the parent body officially known as Comet 55P/Tempel-Tuttle.
The Leonids were identified as far back as 902 AD, and The Perseids identified around 36 AD, making them two of the oldest known meteor showers.
Considered to be one of the most prolific meteor showers in the night sky, they are best seen in the month of November from around midnight (GMT) until dawn, and equivalent local time.
· The Leonids are bright meteors and considered to display one of the most prolific meteor storms, as well as their annual meteor showers.
They are not just visible in the direction of Leo as they can actually be viewed throughout the night earthsky in November, in clear skies, only dimmed by the brightness of a full moon or light pollution caused by city lights.
They’re not regularly visible
· The Leonid Meteor Showers are not visible every year. It has been reported that its meteor shower peak occurs at an average of 15 meteors per hour, travelling at a meteor velocity of 44 miles per second (71 kilometers).
15 meteors per hour is a slow speed compared with other meteor showers.
The Leonids can be easily seen by naked eye from many locations in the winter sky, from North America to Asia, but are best seen as far north as possible.
The Leonids meteor storm occurs every 33 years and is considered to be a spectacular meteor shower, which produces many explosions of light known as Fireballs.
Where do they come from?
Most meteoroids are formed from the bits of space debris that possibly burn off a Comet as it orbits the Sun and expand along the orbit of the comet forming a meteoroid stream.
This Comet is estimated to take around 33 light years to orbit the Sun.
If the Earth passes through this stream of debris some of it will follow along trail towards Earth. As the debris travels the resistance from the surrounding air causes friction and this causes this debris to catch fire, creating fireballs (meteors).
The Leonids Meteor Shower association with the Constellation Leo
The Leo Constellation is named after the lion from Greek Mythology.
The Leo Constellation is one of the oldest known constellations, and ranks as the 12th largest Constellation as one of the original 48 Constellations listed by Greek Astronomer Ptolemy, in the 2nd century.
Leo is one of the official International Astronomical Union (IAU) listed 88 modern constellations as seen in the night sky from Earth.
Where is the Leo Constellation located? –
Constellation Leo is positioned in the second quadrant of the Northern Hemisphere. It is sometimes referred to as being located in the NQ2 Quadrant and occupies an area of 947 square degrees and positioned on the ecliptic.
FACT: The ecliptic is the imaginary line tracing the route that The Sun, the Moon, and the Planets take across the sky, over the year.
Where can Leo be seen?
Co-ordinates of a right ascension, or left ascension and their declination are used to locate all of the Constellations, like Leo.
Leo is one of the most prominent and recognizable Constellations and can be viewed throughout the world. The bright star Regulus (meaning little King or Prince) is a well-known landmark in the night sky, associated with this Constellation, as the heart of the Lion.
The Constellation of Leo lies at 10 hours 30 minutes right ascension and the Declination is + 15 degrees north, between Virgo and Cancer.
It is located at latitudes between +90 degrees and -65 degrees and covers an area of 514 square degrees in the Northern sky.
The Leonids are one of the few meteor showers that are visible from both the Northern Hemisphere and the Southern Hemisphere.
Meet the neighbors
The Constellation Leo is bordered by several Zodiac Constellations:
Accounting for the distances of all the main star and objects within the Constellation of Leo the average distance from Earth is 1535 miles (2470km).
How can you identify the location of any Constellation?
The simplest method for spotting the location of any particular Constellation from Earth is to first of all locate the brightest star in that Constellation, and then look at the neighboring illuminations, to see if you can identify a recognizable pattern.
Leo, and its associated contents, can be spotted in the Northern Hemisphere in spring, also referred to as the Northern sky and in the Southern Hemisphere in autumn time.
This is the direction from which the Leonids Meteor showers originate.
The Leo Constellation is a well-known guide-point in the sky used by astronomers and amateur stargazers, light pollution permitting. One favourite spot for sky-watchers is to look for the pointer stars of the Big Dipper and it is below it.
When to see The Leonids Meteor Shower
The peak month for The Leonid meteor showers associated with Constellation Leo is November.
They are one of the fast moving meteor showers of the year, and bright as their meteors can have an apparent magnitude of -1.5
When the Moon is in its waxing crescent phase and setting before midnight, the sky will be dark and therefore the best conditions for viewing the Leonids.
What’s within the Constellation of Leo?
The Leo Constellation is associated with 2 annual meteor showers known as the ‘ Leonids Meteor Showers – ‘The Leonids’, one apparent in November and a smaller one in January. The bright meteors appear to radiate from the direction of the Constellation of Leo.
These Meteor showers are formed by space rocks, (meteoroids), racing quickly towards Earth.
When any number of meteors enter the Earth’s atmosphere at high speed they catch fire, through friction and look like fireballs or what we know as Shooting Stars (Meteors).
If it survives the trip and it finally hits Earth it is then known as a meteorite. The Leonids are unlikely to actually make contact with Earth.
The 8 Most Common Meteor Showers
There are 8 well-known major meteor showers, listed from the beginning of the year, as follows:
- January – ‘The Quadrantids’, associated with the old astronomically obsolete Constellation of Quadrans Muralis. It is often forgotten as a Constellation. Its asteroid/rock comet of origin is 2003EH1
- April – ‘The Lyrids’, associated with the Constellation of Lyra, is one of the oldest known meteor showers, being observed for over 2,700 years, and recorded in ancient Chinese texts. Comet of origin is C/1861 G1 Thatcher
- May – ‘The Eta Aquarids’, (or Eta Aquariid), associated with the Constellation of Aquarius. Known for speed. Its comet of origin is 1P Halley
- July – ‘The Delta Aquariids’, associated with the Constellation of Aquarius. It is faint and difficult to spot unless there is a full moon. Comet of origin is not known, but 96P Machholz is suspected
- August – ‘The Perseids’, associated with the Constellation of Perseus. This is considered to be the best meteor shower of the year. Its Comet of origin is 109P/Swift-Tuttle is sometimes simply referred to as the Comet Swift-Tuttle
- October – ‘The Orionids’, associated with the Constellation of Orion. This is considered to be one of the most beautiful meteor showers in the year. Its comet of origin is 1P/Halley, like the Eta Aquarids.
- November – ‘The Leonids’, associated with the Constellation of Leo. The rates of showers are low compared to other meteor showers. Its comet of origin is 55P/Tempel-Tuttle
- December – ‘The Geminids’, associated with the Constellation of Gemini. Considered to be one of the best and most reliable annual showers. Its origin is uncertain, could be a rock comet, or the asteroid 3200 Phaethon.
They range from appearing quite faint Shooting Stars to more vibrant meteor storms, with colorful streaks and the occasional Fireballs.
Within the Constellation Leo
The Constellation of Leo is formed by of a number of different components.
The different components housed by the Constellation Leo are mainly Stars, Deep sky objects and Messier objects (galaxies)
Images of many of the largest objects and smallest debris in Space have been captured using professional Space telescopes, such as the NASA Spitzer Space Telescope, operated by NASA, and the famous Hubble Space Telescope
Nothing stands still in the sky. Planets are continually being discovered and lists updated. The Constellations change their positions throughout the year as the Earth rotates around the Sun.
This means our position in space is forever changing and as a result our view of what’s in space changes too, and will continue to do so.
From children to the elderly, we have had an ongoing fascination, with our solar system and star system, from spotting Saturn to identifying the Polar Star, and seeing Full Moons and New Moons. Perhaps it’s because the enormity and variety within it makes us realize just how large and exciting the universe is.
The Leo celestial pole
The celestial pole defines the poles of the celestial equatorial coordinate system.
An object at the Celestial pole has a declination of 0 degrees.
- The declinations for the north celestial pole is +90 degrees
- The declinations for the south celestial pole is -90 degrees
The celestial poles are not permanently in a fixed position against the background of the stars as everything moves in Space.
Leo is located in the northern celestial sky at a +22 degree north declination and a 10 hours right ascension.
Historical significance: the legends, and myths surrounding Constellation of Leo
When it comes to the many recognized constellations in the sky, Leo is one of the larger Constellations, ranking 12th overall and occupying around 2.3% of the sky.
However the origins of the earliest Constellations probably date back to prehistory.
Many ancient civilizations have related the Constellations in the sky to suit their beliefs and creations itself. They have been the subject of folklore and experiences for a very long time.
In many cultures Leo is associated in some way with the Sun, and even the meaning in the zodiac, Leo is a fire sign, representing those born in summer
There are even depictions of this strong and bold Lion in prehistoric cave carvings, in Europe, estimated to date back as far as 38,000 years.
There are many Greek myths and legends surrounding the origin and names of the constellations.
Leo (its Latin name) is quite easy to recognize, as it resembles the outline of a Lion and associated with the myth of Hercules and his 12 trials, where the first was to find and kill the indestructible Nemean Lion. Some believe the lion was placed in the constellations as the king of the beasts.
The Babylonians and the Mesopotamians also recorded details of various bright stars within the Constellations in their Babylonian star catalogues before 100BCE. and referred to a Lion Constellation.
A name meaning Lion was used in many cultures:
- Indian – Simha
- Jewish – Ayre
- Persian – Shir/Ser
- Syrians – Aryo
- Turkish – Artan
The Egyptians believed that the Lion was a very important animal, yet the association of the constellation Leo is with their watering hole, the River Nile.
Christian and Hebrew teachings
There are also references to Leo in the Christian ‘Bible, and it may have a Hebrew root, referring to the tribe of Judah, and commenting on the ruler at the Lion’s feet.
Perhaps this could refer to the fact that the brightest Star in Leo, Regulus, is located at the foot of the constellation Leo and means the little King. Leo could therefore represent the birth of Jesus.
Lions are not native to China but finally arrived from India and Asia.
Leo is associated with the regal guardian lions., usually positioned outside entrance gates. Examples include their protection of Inner Mongolia and as the Buddhist protector of the dharma.
Evidence of the guardian Lions has been found in religious art dating as far back as 208 BC.
The Leo name association in different cultures
Over time different cultures have looked at the night sky and made images from the random bright objects they viewed. Many myths, beliefs, stories and fears followed those sightings.
The name ‘Leo’ comes from the Latin word for ‘Lion’
Ancient Egyptians – associated it with the start of the great flood of the River Nile in Egypt
Old English language – associated it with the arrival of the summer solstice, as it is most visible in March
Fun Facts Summary – Did you know that?
- Planet Earth passes through many debris streams in a year.
- The most active citing of the Leonids meteor storms was in 1833, in the early morning of October 21. It was estimated to have travelled at a speed of 140,000 mile per hour (230,000km/hour)
- The spectacular Leonids meteor storm in 1833 was instrumental in the scientific studying or meteors, their habits and activity
- In 2020, the Orionid Meteor Shower peaked early on Wednesday morning in October 21.
- They are the most prolific meteor shower, with fast moving streams of meteoroids as big as 10mm in diameter and weighing 0.5 grams.
- The gravity of the Planet Jupiter is responsible for pulling the particles in the Meteor showers closer to Earth over time
- A Meteor is heated to a temperature of a temperature of around 3,000 degrees Fahrenheit (1,650 Celsius) as it enters the Earth’s atmosphere. At this heat the Meteor vaporizes and forms a shooting star. The larger ones can explode in a brighter flash known as a Fireball, which can sometime be heard from Earth.
- The height of the average shooting star we can see by naked eye is located about 60 miles high.
- Not all Comets visit the inner Solar System.
- An extinct Comet is one which has lost its ice by coming too close to the Sun
- Constellations like Leo are not part of our Solar System; they are groups of stars that appear to form shapes that are visible with the naked eye from Earth.
- It is Planets such as Jupiter and Saturn that form part of our solar system, other space objects may, or may not pass through the earth’s atmosphere.
- The Sun does not belong to any constellation.
Commonly Asked Questions
Q. Why are Meteor Showers, like The Leonids, best seen in pre-dawn hours?
A. When the Earth rotates it is the side facing the Sun at any given time that attracts more Space Debris. As this area of the sky is directly overhead at dawn, it is recommended to view the Leonids before this time or they may be occluded by debris. The same principle applies when viewing random Shooting Stars.
Q. What’s the difference between a Constellation and an asterism
A. The stars that make up a Constellation have a definite position and form, whereas an asterism is a collection of stars without a fixed position
Q. What prevents us seeing the different meteor showers, meteor streaks, shooting stars and fireballs that usually light up the night sky?
A. Light pollution, fog, city lights and artificial lights all limit our visibility of even the largest objects in the sky at night.
Q. Will the Constellations change over time?
A. The Constellations are continually on the move.
The images we form in our imagination to make objects, shapes and patterns out of the constellations have already shifted over time.
As we view the night skies from Earth they are likely to continue to shift and possibly in time the images may look very different.
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