Compared with the billions of other stars in the universe, the sun is unremarkable. But for Earth and the other planets that revolve around it, the sun is a powerful center of attention. It holds the solar system together; pours life-giving light, heat, and energy on Earth; and generates space weather.

The sun is a big star. At about 864,000 miles (1.4 million kilometers) wide, it could hold 109 planet Earths across its surface. If the sun were a hollow ball, more than a million Earths could stuff inside it. But the sun isn’t hollow; it’s filled with scorching hot gases that account for more than 99.8 percent of the total mass in the solar system. The temperature is about 10,000 degrees Fahrenheit (5,500 degrees Celsius) on the surface and more than 28 million degrees Fahrenheit (15.5 million Celsius) at the core.

Deep in the sun’s core, nuclear fusion reactions convert hydrogen to helium, which generates energy. Particles of light called photons carry this energy through the sun’s spherical shell, called the radiative zone, to the top layer of the solar interior, the convection zone. There, boiling motions of gases (like in a lava lamp) transfer the energy to the surface. This journey takes more than a million years.

The sun’s surface, or atmosphere, is divided into three regions: the photosphere, the chromosphere, and the solar corona. The photosphere is the visible surface of the sun and the lowest layer of the atmosphere. Just above the photosphere are the chromosphere and the corona, which also emit visible light but are only seen during a solar eclipse, when the moon passes between the Earth and sun.

SOLAR WIND AND FLARES

In addition to light, the sun radiates heat and a steady stream of charged particles known as the solar wind. The wind blows about 280 miles (450 kilometers) persecond throughout the solar system. Every so often, a patch of particles will burst from the sun in a solar flare, which can disrupt satellite communications and knock out power on Earth. Flares usually stem from the activity of sunspots, cool regions of the photosphere related to a shifting magnetic field inside the sun.

Like many energy sources, the sun is not forever. It is already about 4.5 billion years old and has used up nearly half of the hydrogen in its core. The sun will continue to burn through the hydrogen for another five billion years or so, and then helium will become its primary fuel. The sun will expand to about a hundred times its current size, swallowing Earth and other planets. It will burn as a red giant for another billion years and then collapse into a white dwarf about the size of planet Earth.

Original article – http://www.nationalgeographic.com

 

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Meditation – Visualized

 

Feelings come and go like clouds in a windy sky. Conscious breathing is my anchor.

Thich Nhat Hanh

Undisturbed calmness of mind is attained by cultivating friendliness toward the happy, compassion for the unhappy, delight in the virtuous, and indifference toward the wicked.

Patañjali

 

Meditation is the dissolution of thoughts in Eternal awareness or Pure consciousness without objectification, knowing without thinking, merging finitude in infinity.

Voltaire

The Way to do is to be.

Lao Tzu

Though I am often in the depths of misery, there is still calmness, pure harmony and music inside me. I see paintings or drawings in the poorest cottages, in the dirtiest corners. And my mind is driven towards these things with an irresistible momentum.

Vincent van Gogh

It is more than probable that I am not understood; but I fear, indeed, that it is in no manner possible to convey to the mind of the merely general reader, an adequate idea of that nervous intensity of interest with which, in my case, the powers of meditation (not to speak technically) busied and buried themselves, in the contemplation of even the most ordinary objects of the universe.

Edgar Allan Poe

 

If the mind falls asleep, awaken it. Then if it starts wandering, make it quiet. If you reach the state where there is neither sleep nor movement of mind, stay still in that, the natural (real) state.

Ramana Maharshi

Meditation is a microcosm, a model, a mirror. The skills we practice when we sit are transferable to the rest of our lives.

Sharon Salzberg