Author Topic: Interesting facts about Sun  (Read 1042 times)

Offline faizun

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Interesting facts about Sun
« on: September 19, 2012, 04:38:01 PM »
    * The Sun is one among the 200 billion stars in our Milky Way galaxy.
    * The Sun is one among the 6000 stars, which is visible to naked eye from the Earth.
    * The mass of Sun is 2 trillion trillion trillion tons.
    * The Sun's energy output is 386 billion billion megawatt.
    * The Earth receives 94 billion megawatt of energy from Sun. This is equivalent to 40,000 times the power requirement of United states.
    * The reaction taking place in Sun is nuclear fusion, same as a Hydrogen bomb.
    * Each second 700 million tons of Hydrogen are converted to 695 million tons of Helium and 5 million tons of energy in the form of gamma rays.
    * Each second the Sun loses 5 million tons of material.
    * The Sun's temperature at its core is 14 million Kelvin.
    * The pressure at the Sun's core is 340 billion times the pressure at the Earth's atmosphere.
    * The density of matter at the Sun's core is about 150 times the density of water in the Earth.
    * It takes up to 50 million years for the energy produced at the core of the Sun to reach its surface.
    * If the Sun were to stop producing energy today, it would take 50 million years for significant effects to be felt at Earth.

[http://www.goldenkstar.com/facts/sun-interesting-facts.htm]
Faizun Nesa
Senior Lecturer of Physics,
Department of Natural Science, FSIT,
Daffodil International University

Offline nayeemfaruqui

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Re: Interesting facts about Sun
« Reply #1 on: February 19, 2013, 03:45:06 PM »
Informative post
Dr. A. Nayeem Faruqui
Assistant Professor, Department of Textile Engineering, DIU

Offline bcdas

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Re: Interesting facts about Sun
« Reply #2 on: July 08, 2013, 11:57:16 AM »
Ok, Good...............but

People with a deep, golden tan are often said to have a healthy glow. Even though exposure to the sun can relieve the discomfort of certain conditions such as arthritis and asthma, the dangers of excessive exposure often outweigh the benefits. Not only can the sun's rays cause you to look older, they can bring on life-threatening conditions as below...........

The Facts

 Ultraviolet rays account for about 6 percent of the sun's rays. These harmful rays cause undesirable effects on your skin. The worst time to be out in the sun is between 10 a.m. and 3 p.m. because that is when the sun's rays are the strongest. Effects of the sun vary due to the atmosphere, time of day and season. They can also depend on how close to the equator you are.
   
Sunburn
        Sunburn is one of the most common effects of the sun on the skin. You will usually notice the symptoms of a sunburn a few hours after exposure. Severe reactions can occur within 12 hours, with symptoms such as pain, extreme fatigue, blistering, swelling, chills, fever, nausea and even delirium. Contact your dermatologist if your pain becomes unbearable, as he can prescribe a topical ointment to help alleviate the swelling.

       
    Aging

        Excessive exposure to the sun can cause you to look much older. The sun's rays change the skin's texture by weakening its elasticity. This causes the skin to sag and appear leathery. Sun worshipers are often plagued with wrinkles as well, making them look 10 to 20 years older than what they are. This is not an immediate effect, but a cumulative effect that gets worse over time.
   
 Cancer

        One of the most devastating effects of sun on the skin is the development of skin cancer. Squamous cell carcinoma, basal cell carcinoma and melanoma are all forms of skin cancer caused by ultraviolet rays. Squamous cell carcinoma is characterized by a crusty, scaly raised bump and can spread to other parts of the body. Basal cell carcinoma appears as a wound that won't heal, or a flat, rounded skin abnormality that does not spread to other parts of the body. Both squamous cell carcinoma and basal cell carcinoma have a high cure rate, up to 95 percent of cases. Melanoma is more deadly, causing 80 percent of skin cancer deaths. Melanoma looks like a large, asymmetrical mole.
 
  Prevention
        Early prevention is the key to beautiful, healthy skin. Avoiding sun exposure during peak hours is ideal, but not always possible. When going out in the sun, it is important to apply sunblock with an SPF value of 15 or higher. Choose a waterproof sunblock if you are going to be in the water. Reapply often, especially if you have been sweating or swimming.


« Last Edit: July 08, 2013, 11:58:49 AM by bcdas »
Bimal Chandra Das
Assistant Professor
Dept. of Natural Sciences, DIU