Proper nounSingular Sun Plural - Sun
Related termsFrom Wiktionary under the GNU Free Documentation License. The Sun is the star at the center of the Solar System. The Earth and other matter (including other planets, asteroids, meteoroids, comets, and dust) orbit the Sun, which by itself accounts for about 99.86% of the Solar System's mass. The mean distance of the Sun from the Earth is approximately 149,598,000 kilometres (92,956,000 mi), and its light travels this distance in 8 minutes and 19 seconds. But it varies throughout the year from a minimum of 147,100,000 kilometres (91,400,000 mi) on 3 January, to a maximum of 152,100,000 kilometres (94,500,000 mi) on 4 July. Energy from the Sun, in the form of sunlight, supports almost all life on Earth via photosynthesis, and drives the Earth's climate and weather. The surface of the Sun consists of hydrogen (about 74% of its mass, or 92% of its volume), helium (about 24% of mass, 7% of volume), and trace quantities of other elements, including iron, nickel, oxygen, silicon, sulfur, magnesium, carbon, neon, calcium, and chromium. The Sun has a spectral class of G2V. G2 means that it has a surface temperature of approximately 5,780 K (5,510 °C) giving it a white color, which often appears as yellow when seen from the surface of the Earth because of atmospheric scattering. This is a subtractive effect, as the preferential scattering of shorter wavelength light removes enough violet and blue light, leaving a range of frequencies that is perceived by the human eye as yellow. It is this scattering of light at the blue end of the spectrum that gives the surrounding sky its color. When the Sun is low in the sky, even more light is scattered so that the Sun appears orange or even red. The Sun's spectrum contains lines of ionized and neutral metals as well as very weak hydrogen lines. The V (Roman five) in the spectral class indicates that the Sun, like most stars, is a main sequence star. This means that it generates its energy by nuclear fusion of hydrogen nuclei into helium. There are more than 100 million G2 class stars in our galaxy. Once regarded as a small and relatively insignificant star, the Sun is now known to be brighter than 85% of the stars in the galaxy, most of which are red dwarfs. The Sun orbits the center of the Milky Way galaxy at a distance of approximately 24,000–26,000 light years from the galactic center, moving generally in the direction of Cygnus and completing one revolution in about 225–250 million years (one Galactic year). Its orbital speed was thought to be 220±20 km/s, but a new estimate gives 251 km/s. This is equivalent to about one light-year every 1,190 years, and about one astronomical unit (AU) every 7 days. These measurements of galactic distance and speed are as accurate as can be, given current knowledge, but this may change as more is learned. Since our galaxy is moving with respect to the cosmic microwave background radiation (CMB) in the direction of Hydra with a speed of 550 km/s, the sun's resultant velocity with respect to the CMB is about 370 km/s in the direction of Crater or Leo. The Sun is currently traveling through the Local Interstellar Cloud in the low-density Local Bubble zone of diffuse high-temperature gas, in the inner rim of the Orion Arm of the Milky Way Galaxy, between the larger Perseus and Sagittarius arms of the galaxy. Of the 50 nearest stellar systems within 17 light-years (1.6×10 km) from the Earth, the Sun ranks 4th in mass as a fourth magnitude star (M = +4.83). From Wikipedia under the
GNU Free Documentation License What is the minimum amount of time in the sun where you should use sunscreen? Q. obviously, one wouldn't wear sunscreen to be outside for 2 minutes and equally obviously you should certainly wear sunscreen to sit on the beach for 2 hours. so whats the actual minimum amount of time in the sun which requires sunscreen? whats the minimum time in the sun that could cause sunburn? assume it's a clear, cloud free sky with direct sun during the peak hours. please provide as specific a number of minutes as possible, not vague recommendations about general sunscreen usage magidge, its clearly not zero minutes. Asked by Danny - Sun Jun 28 17:06:00 2009 - - 5 Answers - 0 Comments How far from the Sun must you travel before its gravitational influence is zero? Q. How far from the Sun must you travel before its gravitational influence is zero? Why is this point a poor choice to define as the boundary of the Solar System? What is a better choice of boundary and why is it better? Asked by GILBERT M - Sat Jun 21 10:06:51 2008 - - 10 Answers - 0 Comments A. you have to be infinitely far away before the gravitational influence is zero. If you picked that as the boundary of the solar system, then the entire universe would be in our solar system. The entire universe would be in every solar system. I am not sure what the actual definition is for the boundary of our solar system. To me, there are two logical boundaries, a practical and an ideal. The practical boundary is the point at which the gravitational effect of the sun is too weak to keep an object in orbit - that will vary with the mass and veloicty of a given object. The ideal boundary would be the point at which the graviational effect of another star is greater than that of the sun - anything farther out than that distance would… [cont.] Answered by Yooper - Sat Jun 21 10:15:04 2008 What is the difference to us between fluorescent light and sun light?
Q. The sun light is the most important to our lives.We get darker from basking in the sun.Do we also get the same effect when we expose by large amount of fluorescent light ? We use lamps to make some water plants grow .What's the difference is it from exposing to the sun light? Asked by Geoffery.T - Tue Jun 16 05:12:52 2009 - - 5 Answers - 0 Comments A. Whether we get darker from basking in sunlight is a function of whether the pigmentation in our skin is functioning as it should; this is a biological process which responds to certain wavelengths of ultra-violet light to be found in sunlight. These wavelengths do not exist in any current design of fluorescent lamps. They are unlikely to exist in any possible fluorescent design because those wavelengths will not penetrate glass, the usual material for fluorescent tubes. Tanning is not related to growth; tanning reduces the skin's vitamin D production and also reduces skin damage from excess sun. Vitamin D production is also NOT directly related to growth. The sun gives off a very wide range of wavelengths, and it does so because of… [cont.] Answered by jesteele1948 - Tue Jun 16 05:50:59 2009 From Yahoo Answer Search: "Sun"
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 news.google.com Wall Street Journal Blogs Woody Allen fans will remember the guy in Annie Hall who had a notion, and felt with some backing he could turn it into a concept, ... 400bn energy plan to harness African sun Independent Siemens, Munich Re Plan 'Visionary' Sahara Project Bloomberg Sun from the Sahara may light up Europe's homes (News Feature) Monsters and Critics.com all 51 news articles » news.google.com The Desert Sun Not that I advocate driving under the influence but a friend of mine received one four years ago he was off-roading and was caught by a BLM cop. ... and more » news.google.com Cape Cod Times The image is from the Website of Kids for Saving Earth a nonprofit organization first founded by 11-year-old Clinton Hill, a Minnesota youth who died of ... From Google News Search: "Sun"  masternewmedia.org 375px x 500px | 89.10kB [source page] in which readers were advised to learn how to write five sentence emails create PowerPoint slides and survive boring meetings It was to my view advice on how to be a business today Photo credit Lars Kristian Schjoenhaug My view is that people are worth more than that that pleasing your boss should be the least of your concerns and that genuine learning means  istockphoto.com 238px x 380px | 26.60kB [source page] Sun Keywords atmosphere background concept evironment eyes face fire girl hair head heat hot idea isolated ray rays red sky sun sunny sunrise suns sunset white  gwest.gats-inc.com 968px x 1288px | 415.30kB [source page] driggs Sun Jul 13 2003 21 20 39 jpg 02 Aug 2005 15 28 368K driggs Sun Jul 13 2003 21 22 39 jpg 02 Aug 2005 15 28 390K driggs Sun Jul 13 2003 21 24 39 jpg 02 Aug 2005 15 28 415K driggs Sun Jul 13 2003 21 26 39 jpg 02 Aug 2005 15 28 444K From Yahoo Image Search: "Sun"  glgroup.com John Berg Mon, 20 Jul 2009 07:40:04 GM The shareholders of . Sun. Microsystems $7.4 billion takeover. Will the be buyer's delight or buyer's remorse for Oracle? Are the winners Oracle's shareholders or . Sun. Microsystems' competitors?  emaxhealth.com ruzik_tuzik Mon, 20 Jul 2009 15:14:47 GM The Arizona Department of Health Services offers useful tips to protect your skin during summer months. Use Sunscreen Every Day! Even on cloudy days, the . sun's. rays can damage your skin. Wear sunscreen with an SPF of 15 or higher.  worldlatestnews.com ians ue, 21 Jul 2009 12:15:15 GM Taregna (Bihar), July 21, In the last three days specially designed . sun. goggles sold like hot cakes in Taregna village near the state capital, where the solar eclipse Wednesday will be best viewed. From Google Blog Search: "Sun" Quotations about the Sun. This theme article is a stub. You can help Wikiquote by expanding it.Sourced
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Global Oscillation Network Group (GONG)
Current Solar Data
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