INTRODUCTION
This feature article will tell you everything you need to know about an aurora from what is a aurora to how are they formed, from the 10 best viewing points to why people visit it. Form its historical significance to the different colours and layers.
Pack your bags and get your cameras ready because you are going to be viewing an aurora pretty soon!!!!!!!!
Are you ready to read about the prettiest thing in the world?????
Let’s get started!!!!!!
TABLE OF CONTENT
1. Introduction
2. What are auroras
3. How are they formed
4. Different colours and layers
5. Viewing auroras
6. Reasons it’s a tourist thing
7. Summary
WHAT ARE AURORAS?
How many of you know what an aurora is? Of course all of you know. And for those of you who don’t auroras are the prettiest thing in the world (as per me).
Northern lights is the common name for the Aurora Borealis in the northern hemisphere.
An aurora is a natural light displayed in the sky mostly seen in high latitude regions.
Most auroras occur in a band known as the auroral zone. Which is a ring shaped region with a radius of approximately 2500km around earth’s magnetic pole. A region displaying an aurora at a particular time is known as an auroral oval. Day to day pictures of the auroral oval are posted on the internet.
The instantaneous distribution of auroras is slightly different night ward of the magnetic pole so that auroral arcs reach furthest towards the equator when a magnetic pole in question is in between the observer and the sun. The aurora can be seen best at this time called the ‘magnetic midnight’.
Folktales and travellers say that auroras can generate sounds like claps! For a long time scientist had been dubious as sound is hard to document and auroras are too high in the sky. However researchers published a record in 2012 saying they recorded clapping sounds. They suggested that these sounds come from the solar particles associated with creating the auroras. Aurora noise is so rare that hearing it is a once in a life experience ! I bet most of you dint know auroras had sound!
HOW ARE THEY FORMED?????????
I know that they are really pretty but how are they formed? Let’s figure out together.
These are the 2 main causes:-
• Dynamo action with solar wind flowing past earth which includes geomagnetic disturbance to precipate particles already trapped in the radiation belt
• Magnetic disturbance involving plasma squeezed towards earth by sudden collision of the magnotail.
The main findings have been that auroral arcs and other bright forms are due to electrons which have been accelerated during the final few 10000 km or so of their plunge into the atmosphere. These electrons are called auroral partials.
Auroras result from emission of photons in the earth’s upper atmosphere resulting from a exited state to ground state then oxygen emission and nitrogen emission take place showing different colours.
Bright auroras are generally associated with bierkland currents which flow down to the ionosphere on one side of the pole and out of the other. In between some of the currents connect directly through the ionosphere layer. The rest detours leaving again through the field lines closer to the equator and closing through the ‘practical ring currents’ carried by magnetically trapped plasma.
The aurora borealis form when charged particles emitted from the sun during a solar flare penetrate the earth’s magnetic shield and collide with atoms and molecules in our atmosphere these collisions result in countless bursts of light called photons which make up the aurora.
DIFFERENT COLORS AND LAYERS
Haven’t you ever wondered why the auroras have so many different colours? Because I have. Take my hand and lest explore.
When photons are at ground state they take different colors.it is called oxygen emission when photons take green or orange red depending on the amount of energy absorbed and it’s called nitrogen emission when they take blue or red colour, blue if the atoms regains a electron after it has been ionized and red if it returns to ground state from exited state.
Auroras take many different forms. A typical aurora consists of these forms appearing through the night sky.
Red-at the highest altitude exited atomic oxygen emits red. Low concentration of atoms and low sensitivity of the eyes at this wavelength make this colour visible only under certain circumstances with more intense solar activity. The low amount of oxygen atoms and their very gradual diminishing concentration is responsible for the faint gradual appearance of the top parts of the ‘curtains’.
Green- at lower altitudes more frequent collisions suppress this mode and the green dominates. Fairly high concentration of atomic oxygen and high eye sensitivity in green makes green auroras most common. The exited molecular nitrogen plays its role here as well as it can transfer energy by collision to an oxygen atom which then radiates away at the green wavelength. The rapid decrease of concentration of atomic oxygen below about 100 km is responsible for the abrupt looking ends of the bottom parts of the ‘curtains’.
Yellow and pink-yellow and pink are a mixture of blue and green.
Blue (my fav)-at yet lower altitudes atomic oxygen is not common anymore and ionized molecular nitrogen takes over the visibe light emission. It radiates a large number of wavelengths in both red and blue parts of the spectrum. Blue and purple emission typically at the bottom of the ‘curtains’ show up at the highest level of solar activity.
VIEWING AURORAS
Now we know all about auroras let’s see some.
The best place to see a aurora is near the magnetic poles. These include areas of northern Greenland. The Scandinavian coast, Siberia (brrrrrr!!!!!!!) and Alaska in the north and Antarctica in the south.
Now the 10 best Aurora viewing spots.
10-Ushvain, Argentina
9- South Georgia Island
8- Stewart Islands, New Zealand
7- Tasmania, Australia
6- South Pole Antarctica
5- Kangelussaug, Greenland
4- Murmask, Kola Peninsula, Russia
3- Tormsa, Norway
2- Yellowknife, Northwest territory, Canada
1- Denali National Park, Alaska
An Auroral viewing destination, Yelloknife boasts the highest percentage of auroral sightings. The Yelloknife is situated in an advantageous position under the Northern Auroral oval based on magnetic latitude. This area has high percentage of clear skies, to see the aurora clearly.
WHY IS AURORA A TOURIST THING?????????
Some of you may have wondered why aurora is a tourist spot. Isn’t it obvious? The beauty, the joy you get when you see one. The happiness the warmth………..why won’t you want to see it?
Auroras are the perfect mood setters and holiday makers. Every year loads of people are found travelling to view the aurora at different times of the year.
Some auroral events have historical significance. Auroras that result from the great geomagnetical storm on both 28th august and 2nd September 1859 are thought to be the most spectacular in recent recorded history. The aurora on 2nd September was extraordinarily bright.
SUMMARY
In this feature article you learned about what an aurora is, how it is formed, the different magnificent colours and how they get their colour, how and where to find auroras, the 10 best spots and why it is a tourist thing.
You also learned they are the prettiest thing in the world!!!!!!!!!!!!!!
Hope you enjoyed reading about auroras and you are all set to see one soon!
AKNOWLEDGEMENTS
Wikipedia
Exploratium
How stuff works
Aurora hunters
Aurora village
This feature article will tell you everything you need to know about an aurora from what is a aurora to how are they formed, from the 10 best viewing points to why people visit it. Form its historical significance to the different colours and layers.
Pack your bags and get your cameras ready because you are going to be viewing an aurora pretty soon!!!!!!!!
Are you ready to read about the prettiest thing in the world?????
Let’s get started!!!!!!
TABLE OF CONTENT
1. Introduction
2. What are auroras
3. How are they formed
4. Different colours and layers
5. Viewing auroras
6. Reasons it’s a tourist thing
7. Summary
WHAT ARE AURORAS?
How many of you know what an aurora is? Of course all of you know. And for those of you who don’t auroras are the prettiest thing in the world (as per me).
Northern lights is the common name for the Aurora Borealis in the northern hemisphere.
An aurora is a natural light displayed in the sky mostly seen in high latitude regions.
Most auroras occur in a band known as the auroral zone. Which is a ring shaped region with a radius of approximately 2500km around earth’s magnetic pole. A region displaying an aurora at a particular time is known as an auroral oval. Day to day pictures of the auroral oval are posted on the internet.
The instantaneous distribution of auroras is slightly different night ward of the magnetic pole so that auroral arcs reach furthest towards the equator when a magnetic pole in question is in between the observer and the sun. The aurora can be seen best at this time called the ‘magnetic midnight’.
Folktales and travellers say that auroras can generate sounds like claps! For a long time scientist had been dubious as sound is hard to document and auroras are too high in the sky. However researchers published a record in 2012 saying they recorded clapping sounds. They suggested that these sounds come from the solar particles associated with creating the auroras. Aurora noise is so rare that hearing it is a once in a life experience ! I bet most of you dint know auroras had sound!
HOW ARE THEY FORMED?????????
I know that they are really pretty but how are they formed? Let’s figure out together.
These are the 2 main causes:-
• Dynamo action with solar wind flowing past earth which includes geomagnetic disturbance to precipate particles already trapped in the radiation belt
• Magnetic disturbance involving plasma squeezed towards earth by sudden collision of the magnotail.
The main findings have been that auroral arcs and other bright forms are due to electrons which have been accelerated during the final few 10000 km or so of their plunge into the atmosphere. These electrons are called auroral partials.
Auroras result from emission of photons in the earth’s upper atmosphere resulting from a exited state to ground state then oxygen emission and nitrogen emission take place showing different colours.
Bright auroras are generally associated with bierkland currents which flow down to the ionosphere on one side of the pole and out of the other. In between some of the currents connect directly through the ionosphere layer. The rest detours leaving again through the field lines closer to the equator and closing through the ‘practical ring currents’ carried by magnetically trapped plasma.
The aurora borealis form when charged particles emitted from the sun during a solar flare penetrate the earth’s magnetic shield and collide with atoms and molecules in our atmosphere these collisions result in countless bursts of light called photons which make up the aurora.
DIFFERENT COLORS AND LAYERS
Haven’t you ever wondered why the auroras have so many different colours? Because I have. Take my hand and lest explore.
When photons are at ground state they take different colors.it is called oxygen emission when photons take green or orange red depending on the amount of energy absorbed and it’s called nitrogen emission when they take blue or red colour, blue if the atoms regains a electron after it has been ionized and red if it returns to ground state from exited state.
Auroras take many different forms. A typical aurora consists of these forms appearing through the night sky.
Red-at the highest altitude exited atomic oxygen emits red. Low concentration of atoms and low sensitivity of the eyes at this wavelength make this colour visible only under certain circumstances with more intense solar activity. The low amount of oxygen atoms and their very gradual diminishing concentration is responsible for the faint gradual appearance of the top parts of the ‘curtains’.
Green- at lower altitudes more frequent collisions suppress this mode and the green dominates. Fairly high concentration of atomic oxygen and high eye sensitivity in green makes green auroras most common. The exited molecular nitrogen plays its role here as well as it can transfer energy by collision to an oxygen atom which then radiates away at the green wavelength. The rapid decrease of concentration of atomic oxygen below about 100 km is responsible for the abrupt looking ends of the bottom parts of the ‘curtains’.
Yellow and pink-yellow and pink are a mixture of blue and green.
Blue (my fav)-at yet lower altitudes atomic oxygen is not common anymore and ionized molecular nitrogen takes over the visibe light emission. It radiates a large number of wavelengths in both red and blue parts of the spectrum. Blue and purple emission typically at the bottom of the ‘curtains’ show up at the highest level of solar activity.
VIEWING AURORAS
Now we know all about auroras let’s see some.
The best place to see a aurora is near the magnetic poles. These include areas of northern Greenland. The Scandinavian coast, Siberia (brrrrrr!!!!!!!) and Alaska in the north and Antarctica in the south.
Now the 10 best Aurora viewing spots.
10-Ushvain, Argentina
9- South Georgia Island
8- Stewart Islands, New Zealand
7- Tasmania, Australia
6- South Pole Antarctica
5- Kangelussaug, Greenland
4- Murmask, Kola Peninsula, Russia
3- Tormsa, Norway
2- Yellowknife, Northwest territory, Canada
1- Denali National Park, Alaska
An Auroral viewing destination, Yelloknife boasts the highest percentage of auroral sightings. The Yelloknife is situated in an advantageous position under the Northern Auroral oval based on magnetic latitude. This area has high percentage of clear skies, to see the aurora clearly.
WHY IS AURORA A TOURIST THING?????????
Some of you may have wondered why aurora is a tourist spot. Isn’t it obvious? The beauty, the joy you get when you see one. The happiness the warmth………..why won’t you want to see it?
Auroras are the perfect mood setters and holiday makers. Every year loads of people are found travelling to view the aurora at different times of the year.
Some auroral events have historical significance. Auroras that result from the great geomagnetical storm on both 28th august and 2nd September 1859 are thought to be the most spectacular in recent recorded history. The aurora on 2nd September was extraordinarily bright.
SUMMARY
In this feature article you learned about what an aurora is, how it is formed, the different magnificent colours and how they get their colour, how and where to find auroras, the 10 best spots and why it is a tourist thing.
You also learned they are the prettiest thing in the world!!!!!!!!!!!!!!
Hope you enjoyed reading about auroras and you are all set to see one soon!
AKNOWLEDGEMENTS
Wikipedia
Exploratium
How stuff works
Aurora hunters
Aurora village
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