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A solar eclipse is a phenomenon caused by the interposition of the Moon between the Sun and the Earth, dimming the sun light either entirely or partially.

Eclipses are more common than you might think, but at a particular site on Earth, you can see a total solar eclipse only once every 360 years.

Why does a solar eclipse occur?

As you know, the moon, Earth and other planets and satellites spin around their axis and at the same time orbit around the Sun. The duration of the orbits varies according to the distance from the sun, so at different times of the year, the planets are in different positions.

Solar eclipses occur only if the moon is in the new moon phase.
When the moon is in the new moon phase, it is orbiting very close to the Sun from a perspective seen from Earth, and that is when a solar eclipse can happen. Strictly speaking, solar eclipses occur only if the moon is in the new moon phase, but this obviously does not mean that they can happen every month. Sun and moon eclipses would occur every month only if the moon rotated in the same plane in which the Earth does around the Sun, called the ecliptic plane.

Another important issue is that the moon is at a distance from earth that is similar in size to the sun, so it can perfectly cover the sun when it passes in front of it in the case of total eclipses.

Each year there are between 2 and five eclipses, and every 100 years occur about 240.

Characteristics of a solar eclipse

On average, a total solar eclipse occurs every 18 months and lasts no more than a few seconds or minutes. Each year there are between 2 and five eclipses, and every 100 years occur about 240. However, there are no more than two total eclipses every year.

In a solar eclipse, the umbra is the shadow projected on the Earth and produced by the moon when it completely blocks the light from the Sun; therefore the people on such area see a total eclipse. In contrast, a softer shadow product of a partially covered sun is the penumbra; evidently, people that experience the penumbra see a partial eclipse.

What are the types of solar eclipses?

There are four types:

Total eclipse.
It is only visible from a small area of ​​the Earth where the moon completely covers the Sun. People in the center of the moon’s shadow are the ones who can see a total solar eclipse since the umbra passes in that area of ​​the earth’s surface.

During this type of eclipse, you can observe the chromosphere, which is the outermost zone of the Sun, along with the solar corona and other protrusions.

Annular eclipse.
This kind of phenomenon happens when it is only possible to observe a small section of light in the form of a ring from the disk of the Sun since the Sun and the Moon are aligned, but the size of the latter is smaller than the apparent dimension of the Sun seen from the Earth.

types of solar eclipses.

Partial eclipse.
In this type of eclipse, only a part of the Sun’s disk is visible, so the crown and the chromosphere can not be seen. The shadow of the Moon passes through an area of ​​the earth’s surface, and it is called the penumbra; therefore, a person located in this area observes a partial eclipse.

Hybrid eclipse.
A hybrid eclipse is the fourth type, but it is very unusual. It happens when the eclipse is total in some regions of the terrestrial surface, while in others it is seen like annular eclipse.

IMPORTANT! You should not observe the solar eclipse directly with your eyes; A special filter must be used to protect your eyes. Otherwise, you risk damaging your retina irreversible to the point of losing your sight.

Eclipses in culture

Despite not affecting humans, solar eclipses were associated with bad omens and mythological events by some ancient cultures. For example, the Vikings believed that during eclipses wolves pursued the sun or the moon and managed to catch them. This belief of beings who ate the sun or the moon was common in many ancient cultures so that people used to bang objects hard enough to make a sharp noise that would frighten the evil creature.

One of the myths that still survive in some parts of the world is that these eclipses can be dangerous for pregnant women and their unborn children, but this belief has no scientific basis. However, it is important to remark that you should not watch the solar eclipse directly with your eyes without a proper filter to avoid eye damage.

Photo Courtesy of NASA

Sun

The Giant Star

 

The Sun is not a planet, it is a star.  Most people forget that the Sun isn’t a planet but it’s really the brightest star in the Solar System. The Sun is almost a perfect sphere shape and has hot plasma – in fact it is made up of hot plasma with a unique magnetic field system also.  Though, it is thought that the sun is going to be made up almost of helium, this is a small portion and the remainder is of hydrogen. It is said to be a lot of different and heavy elements found on the sun which includes iron, carbon, oxygen, neon and a lot of other elements.

Around 4.5 billion years ago, was when the earth was formed because of the collapse of a molecular cloud. It is referred to the big bang which helped formed the solar system. The mass of the sun started to become hotter and hotter as the days past in the beginning of the sun’s formation.

The sun is the brightest star in the solar system and it is around 85% brighter than all of the stars in the entire Milky Way galaxy. Most of the stars are considered to be red dwarf stars; the sun is a necessity when it comes to keeping the earth alive and the human population alive also.

The actual distance of the sun from the earth is about 149.6 million kilometres which is a tremendous distance but it is not that far away actually. The light coming from the sun can travel to the earth in around 8 minutes and 20 seconds; and the energy of the sunlight will help to support every single life form on earth. It will run the different weather, seasons and even the climate of the earth also.

The prehistoric era has to be the time in which the sun had most effect on the earth; and the sun is a star that has taken its time to form. It wasn’t always the size as it is now; it did take many years to form it size and become stronger and stronger and has continued to get brighter in the sky also.

Everyone can view the sun from earth though it is not going to be wise to stare directly at the sun because it can cause damage to the eyes. It will be wise not to directly stare at the sun but wear protective eye wear when it comes to looking at the sun. Though, the sun can be very harmful to the skin because too much from rays the sun gives off, can cause damage to the skin including some skin cancers.

The sun image
The Giant Star / Photo courtesy of NASA

Core

The Sun’s core makes up almost 25% of the solar radius and has a huge density of almost 150 g/cm.  The temperatures of the sun is going to be certainly very hot at a possible 15.7 million K (Kelvin) and this is certainly a temperature no human could stand.

The core of the sun is going to be the only part of the sun that is going to offer thermal energy through fusion.  Almost 99 percent of all power which is generated from the sun comes from the radius and the rest of the sun gets is energy from radiation coming from the core also.  However, the energy that comes from the core will have to go through a variety of layers of the sun to get to the surface or the outside of the core. It will need to travel to the solar photosphere where it will go out into the space; it will go into space as sunlight or even as kinetic energy.

There are gamma rays coming from the sun which is released in fusion. They don’t get far though as they are trapped basically in the atmosphere of the sun and is kept close to the sun.  Radiation can take a lot of time to actually reach the surface of the sun – almost ten thousand years and in some cases, longer. However, neutrinos can reach the surface within seconds which offers energy going to the surface and space.

Atmosphere

Some part of the Sun which is found above the photosphere can be known as the solar atmosphere. The solar atmosphere can actually be seen via a telescope but the telescope must go through the electromagnetic spectrum of the Sun.

The layers and layers on the suns interior is going to be around 2000 km thick and there are going to be several layers in all. Though the sun isn’t just orange or yellow; it is a mixture of colors because have a lot of bright gases circling and as a result there are many more bright colors that shine through.

The temperatures of the sun continue to get hotter and hotter as the layers go deeper. There are going to be times when the sun looks as though it has a whip throwing itself out from the sun and it can resemble a string of fire trying to escape. The sun continues to do this and has done this because it’s a way of some energy of escaping.

Sun star
Solar Flare / Photo courtesy of NASA

Earth’s fate in the future?

There are some studies which have claimed that the Sun will continue to grow and when it does, it will almost disintegrate the Earth. However, if the earth does survive, it could mean that all of the water sources on earth will dry up and be lost in space. This will destroy the entire earth and the population because the intense heat from the sun will be all too much to bear for anyone.

This is because the temperatures are increasing and it is said even though it’s moving slowly in many billions of years, there could be big problems rising because of this.

Another theory says that many believe that in billions of years, the sun will eventually cool down and will expand.

The Source of Energy

The sun is going to provide the earth will its main source of energy.  Many people don’t think about this but it’s true because this is where most energy sources come from and it has become something that is required to help keep the earth revolving and working correctly.  Though, there are other sources of energy from outer space but this is only going to be due to the death of another star and the remnants of that star.

How this works, is that the materials of the star will be trapped into the earth and the earth’s crust which will offer a rise of geothermal energy.  This will offer more volcano forms on earth and this will help to add fuel for nuclear reactors.  Strangely though, there is less power heading to the surface of the earth.

Though, when it comes to solar energy, this is possible to harness in a variety of options.  However, this is going to help natural and synthetic things such as plants because plants will take in the sunlight and help it to grow.  The sunlight can convert the energy such as oxygen and even some carbon compounds which will offer direct heat or even electrical conversion.  This is done via solar cells which are used by the solar power equipment; this will help to generate electricity.

This is how most of the planet runs because it is a vital source of energy and very much needed.  The sun is close to the Milky Way Galaxy, particularly at the Orion Arm.

Facts on Video

Solar flares

 

The definition of a solar flare is a very sudden, intense, and fast change in brightness. These explosions or ejections happen at different intensities and frequencies, from several per day to one every week. There are times when the sun gives of very few or low-intensity flares, during its minimum stage of the cycle. The solar flares will gain in intensity until the height of the cycle.

What causes solar flares?

When magnetic energy builds up in the solar atmosphere and needs to be released, a solar flare occurs. In a typical flare, there are three stages:

 

  1. The release of magnetic energy is activated in the first stage—the precursor stage. In this stage, soft x-ray emission will be detected.
  2. In the impulsive stage, electrons and protons are accelerated to energies well over 1 MeV (1 million electron volts). Hard x-rays, radio waves, and gamma rays are emitted during this stage.
  3. The decay stage is the third and final stage. During this stage, the slow build up and decay of soft x-rays are detected.

 

The stages of solar flares vary in length and there is no reliable way to predict their intensity or duration. Any of these stages can take as little as a few seconds to as much as an hour in length.

Even though solar flares will typically happen on areas of the sun where the magnetic fields are higher, it’s still not entirely clear what causes the flares to happen. Scientists are still unsure as to how the magnetic energy is transformed, or what causes the acceleration of the particles.

How solar flares are detected

Solar flares cannot be seen by the naked eye and this shouldn’t be attempted. Specialized instruments are used to detect the flares. Optical telescopes can be used to see flares. There are also radio telescopes which capture the wavelengths of solar flares. Space telescopes are also used to capture images of flares and transmit the data to earth. While most solar flares go undetected by most people, the stronger flares have been known to knock out communications and electrical systems.

Solar flares are what cause the aurora borealis and the aurora australis. These beautiful light shows are the result of energetic particles in the magnetosphere.

Stellar Flame
A huge solar Flare / Photo courtesy of NASA

Dangers of solar flares

Because there is no way to predict solar flares, the greatest danger is to astronauts in space. The radiation from the flares can affect any astronauts outside of their ships much faster and stronger than anyone on earth. The solar flare with the largest concentration of protons (directly measured to date) happened on January 20, 2005. At the time, astronauts had only 15 minutes to get to shelter.

Other problems caused by solar flares include the orbital decay of low-orbiting satellites, interference with short-wave radio communication, and damage to spacecraft electronics. In general, the solar winds caused by solar flares can affect the earth’s magnetosphere and create radiation hazards for astronauts, cosmonauts, and spacecraft.

Famous solar flares

The first solar flare to be observed was also the most powerful flare ever detected. On September 1, 1859, a British astronomer, Richard Carrington and an observer, Richard Hodgson reported the mega flare. In this event, the flare was visible to the naked eye and caused borealis to be seen as far as Hawaii and Cuba. The flare set telegraph wires on fire and left a trace of nitrates and beryllium-10, which can still be measured today in Greenland.

As recently as 2003, the largest modern-time flare was detected and measured. Because it saturated the devices used to detect the intensity of solar flares, it’s possible that the classification of the flare is much higher than recorded. This solar flare enabled astronomers to set the bar higher, knowing that the flares can get that much stronger.

 

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