How Aurora Phenomena Happen
Do you know about aurora? Can you tell me how aurora occurs? Well, let me explain it. An aurora (Latin word mean “sunrise”) is natural light display in the sky in the poles (north and south) caused by the collision of energetic charged particles with atoms in the high altitude atmosphere. In the northern latitude, the effect is known as aurora borealis (aurora: the goddess dawn, borealis: north wind). While in the Antarctic region, the effect is known as aurora australis. They illuminate the northern and southern horizon as greenish glow or sometimes faint red, occasionally blue but most often in fluorescent green. Auroras can be seen at night because their light is not as strong as the light of the day.
The aurora phenomenon occurs when the sun produces solar wind. Solar wind is a stream of electrons and protons which are released from the sun due to the high kinetic energy. These particles are charged and contain energy, which means they contribute to electricity. In other way, our planet is surrounded by a super-sized magnetic sheath which is usually called the Magnetic Field of the Earth. Sometimes this solar wind hits the Earth. Some of these charged particles lead to the poles of the earth at a speed that keeps growing. The collision between these particles and atoms present in the earth’s atmosphere, it releases the energy that causes the formation of colorful auroras at the poles of the earth, which looks like a big circle around the pole.
Why Aurora is only found in the earth’s poles? This is because the north and South Pole magnetic field is very strong compared to other regions. The poles of this magnetic field pull the protons and electrons from the solar wind. So the phenomenon is more common in the Polar Regions.
However, sometimes the Aurora can also appear at the top of the mountain in a tropical climate, but this phenomenon is extremely rare. Aurora phenomena have been observed on other planets than Earth that have a magnetic field, such as Jupiter, Saturn and more recently Mars. It is believed to be a widespread phenomenon in the Solar System and beyond
An aurora is a flickering light mostly caused by the sun's radiation, usually found near the poles. They come in red, green and occasionally blue, and can sometimes resemble fire. In fact, the Roman Emperor Tiberius thought a city was on fire, so he sent fire engines to that city. The city on fire was actually a city against a backdrop of a red aurora.
An aurora can happen in the Arctic, around the North Pole (Aurora borealis - Dawn of the North - there it is also called the Northern Lights) or in the Antarctic around the South Pole (Aurora australis - Dawn of the South). An aurora can often be seen from long distances and stretching in the sky many hundreds of kilometers or miles.
Auroras can only be seen at night because their light is not as strong as the light of day. For instance, faint stars can be seen through the aurora. However they do happen during the day as well.
Aurora occurs when the Sun sends off matter we call particles to the empty space. These particles are charged and contain energy, which means they contribute to electricity. These particles flying in space are called "solar wind". Sometimes the solar wind hits Earth. Earth has a protection shield of energy around it. This is called the "magnetic field" and forms an elongated sphere around the Earth called the "magnetosphere". The magnetic field wards off most of the solar wind. At high-latitude areas (polar areas), the magnetic field is less powerful, and cannot protect Earth from the solar wind. There the particles of the solar wind and coming from the magnetosphere may hit the particles of the air (Earth's atmosphere). When they hit, the atmosphere is heated and excited and the excess energy gets away, a phenomenon which we see as moving lights in the sky above 100 km altitude typically. An aurora can also occur following a solar event called a coronal mass ejection (CME), when the charged particles rip through the electromagnetic field because of their power.
Auroral phenomena have been observed on other planets than Earth that have a magnetic field, such as Jupiter, Saturn and more recently Mars. It is believed to be a widespread phenomenon in the Solar System and beyond.
Many legends are associated with the aurora, in all countries where this phenomenon regularly occurs
Aurora is an electro-static phenomenon, characterised by a bright glow and caused by the collision of charged particles in the magnetosphere with atoms in the Earth’s upper atmosphere.
Ultimately, the source lies in the solar wind, a fast-moving stream of particles constantly flowing from the Sun that carries the Sun’s magnetic field out into space. The solar wind, typically moving at 250 miles (400 kilometers) per second, flows past Earth’s magnetic field and molds it into an elongated bubble or cavity, compressing its sunward side and stretching its night side far beyond the Moon’s orbit.
Under certain conditions, the solar wind’s magnetic field can merge with Earth’s, creating electrical currents that drive protons and electrons into the polar atmosphere. Powerful events occurring on the Sun can drive enormous changes in the solar wind, increasing both its speed and density and enhancing its effect on Earth.
An aurora is usually observed in the night sky, particularly in the polar zone. For this latter reason, some scientists call it a “polar aurora” (aurora polaris).
Aurora Coloured light in the night sky near the Earth’s magnetic poles, called aurora borealis (northern lights) in the northern hemisphere and aurora australis (southern lights) in the southern hemisphere.
