by Ken Lund
Question by : How do you calculate the radius of the penumbra during a solar eclipse?
What is the formula to calculate the radius of the penumbra? I'm looking for the pure formula not necessarily in regards to the Earth and the moon.
If it helps, the formula for the length of the umbra can be found here: http://en.wikipedia.org/wiki/Eclipse
Best answer:
Answer by coldfieldgirlYou must know the umbra can fall on Earth's surface, but also it can just not fall on it (it is an annular eclipse then!).
So for your calculation of the penumbra on Earth's surface, the whole distance between Earth and Moon must be taken.
If you suppose:
s = radius Sun
m = radius Moon
N = distance Moon to Sun
D = distance Moon to Earth
then you can do the following:
angle A of one penumbra line = ArcTan ( ( s + m ) / N )
and the radius of the penumbra becomes m + D * Tan ( A )
What do you think? Answer below!
My name is Kurt and I'm back in Stellarium for what will be a regular series on interesting astronomical sights and events you can view each month! In this video we take a quick tour of popular springtime objects, including many galaxies and some early views of summer observing targets. The planets Venus, Mars and Saturn are dominating the night skies and always worth taking a look at. On May 20th at sunset there will be an annular solar eclipse visible from the US, favoring those near the west coast. Information and maps for the May 20th eclipse: en.wikipedia.org Get your solar eclipse glasses and support Astronomers Without Borders here: www.astronomerswithoutborders.org Stellarium is a free open source planetarium software available for Windows, Mac and Linux. It shows a realistic sky, just like what you see with the naked eye, binoculars or a telescope from your location. Get Stellarium for free here: stellarium.org Click 'Like' to let me know if you want me to continue this series in Stellarium, ask questions in the comments and subscribe if you'd keep up with my channel! Background music Kevin MacLeod - incompetech.com
Wednesday, August 1, 2012
How do you calculate the radius of the penumbra during a solar eclipse?
Total solar eclipse today and pregnant women? Myths & rumors.
Question by Chloe'sMommy: Total solar eclipse today and pregnant women? Myths & rumors.
Hey i live in USA, and according to Yahoo! we're going to have a total solar eclipse, I am a very curious pregnant women so i was wondering who all believe in those myths and rumors that a pregnant woment shouldnt step outside her house when the eclipse is happening and close all her windows and shades? And who are the brave souls who are going to watch it??
This is the site where the eclipse was mentioned. http://news.yahoo.com/s/space/20080731/sc_space/solareclipsefridaytofascinatemillions
Best answer:
Answer by rhsaundersNo eclipse will have the slighest effect on any pregnancy.
Give your answer to this question below!
On on end there is an understanding of the solar eclipse being a natural phenomenon. On the other, there is this strong religious belief that calls it a bad omen.
Video Rating: 0 / 5
What Are Black Friday and Cyber Monday and How Can You Make the Most of Them?
by Michael Holden
What Are Black Friday and Cyber Monday and How Can You Make the Most of Them?
Two dates we're excited about this November are Black Friday and Cyber Monday.What are Black Friday and Cyber Monday I hear you cry?Black Friday is the traditional start of the shopping sales in the US. The day follows the American Thanksgiving holiday and is one of the biggest shopping days in the retail calendar. On the Friday, many US retailers open early, often 4am, to launch their sales and take advantage of the increased number of shoppers. This year the date to remember is November 25th.Following the Friday comes Cyber MondayCyber Monday was created by companies to persuade people to shop online and compliment the Friday sales by extending the shopping holiday weekend to Monday. According to Shop.org, who originally coined the phrase, Cyber Monday is now one of the biggest online shopping days of the year. Cyber Monday falls on November 28th this year.But wait there's more!Cyber Black FridayCyber Black Friday (or CBF) was created in 2009 after observers noted that online retailers were launching their holiday sales before Cyber Monday to compete with the Black Friday brick and mortar sales frenzy. According to Talya Schaeffer, founder of CBF, "Cyber Friday sales are typically the largest of the season. Online retailers are hoping that by offering early discounts, consumers will shop early and often".What does it all mean for you?It's a great time to be shopping online. With retail struggling and competition in the bricks and mortar retail sector strong, there should be some big discounts being offered by many US retailers ready to launch the holiday season and with the added incentive of free shipping deals, the weekend of November 25th is the time to be shopping online in the USA.With the downturn in retail sales, and the recession still biting, many retailers may not be waiting until the weekend of November 25 to begin discounting their products. Smart retailers will know that because the US dollar is flat against many international currencies, overseas sales may be the key to recovering their bumper Christmas profits. So the free delivery offers may start early and extend beyond the US borders to international markets for orders above a certain value. This is an attractive offer for many international buyers and shoppers worldwide should be on the lookout for Black Friday and Cyber Monday (and Cyber Friday!) deals as well as free shipping.
Read more on Black Friday deals at as well as the latest deals from American online shopping stores Article Source:
http://EzineArticles.com/?expert=James_Anthony_Harris
Had a dream about an eclipse and ring around another moon?
by the_exploratorium
Question by Pretty Blunt: Had a dream about an eclipse and ring around another moon?
So I had a dream about a lunar eclipse and then I looked off to the left and saw another moon and this moon had a ring around it. What do you think this means. i don't think i was doing anything significant in the dream just looking up at the moons. But there were two at a time, one was eclipsed and the other had a ring around it.
Best answer:
Answer by Zia LuciaNot to worry, Pretty Blunt. Your dreams are not about moons or omens or anything like that. Your dream is about you. The two moons represent two persons or things, one that is fading and other that is drawing your attention.
Let's say the moons might be two friends. The one in eclipse is shadowed, representing someone moving away or distancing themselves from you. The other is someone who wants to draw your attention by putting a circle around themselves.
Alternatively, the moons might symbolize two opportunities: two job offers or two courses of study or two vacation possibilities. They might be anything, but one is resisting attention and one is trying to get your attention.
Know better? Leave your own answer in the comments!
Visual Clarity and Comfort
by NASA's Marshall Space Flight Center
Visual Clarity and Comfort
Article by Yifer
Visual Clarity and Comfort - Shopping
Search by Author, Title or Content
Article ContentAuthor NameArticle Title
Home
Submit Articles
Author Guidelines
Publisher Guidelines
Content Feeds
RSS Feeds
FAQ
Contact Us
Sunglasses of particular shapes may be in vogue as a fashion accessory. Fashion trends can also draw on the "cool" image of sunglasses.This can be true for people with severe visual impairment, such as the blind, who may wear sunglasses to avoid making others uncomfortable. The assumption is that it may be more comfortable for another person not to see the hidden eyes rather than see abnormal eyes or eyes which seem to look in the wrong direction. People may also wear sunglasses to hide dilated or contracted pupils, bloodshot eyes due to drug use, recent physical abuse (such as a black eye), exophthalmos (bulging eyes), a cataract, or eyes which jerk uncontrollably.Various types of disposable sunglasses are dispensed to patients after receiving mydriatic eye drops during eye examinations.Sunglasses offer protection against excessive exposure to light, including its visible and invisible components.The lenses of polarised sunglasses reduce glare reflected at some angles off shiny non-metallic surfaces such as water. They are popular among fishermen because they allow wearers to see into water when normally only glare would be seen.The most widespread protection is against ultraviolet radiation, which can cause short-term and long-term ocular problems such as photokeratitis, snow blindness, cataracts, pterygium, and various forms of eye cancer. Medical experts advise the public on the importance of wearing sunglasses to protect the eyes from UV; for adequate protection, experts recommend sunglasses that reflect or filter out 99-100 % of UVA and UVB light, with wavelengths up to 400 nm. Sunglasses which meet this requirement are often labeled as "UV400." This is slightly more protection than the widely used standard of the European Union (see below), which requires that 95 % of the radiation up to only 380 nm must be reflected or filtered out. Sunglasses are not sufficient to protect the eyes against permanent harm from looking directly at the Sun, even during a solar eclipse.More recently, high-energy visible light (HEV) has been implicated as a cause of age-related macular degeneration;[10] before, debates had already existed as to whether "blue blocking" or amber tinted lenses may have a protective effect. Some manufacturers already design to block blue light; the insurance company Suva, which covers most Swiss employees, asked eye experts around Charlotte Rem
Michael Kors Watches Michael Kors Ladies Dylan Chronograph Navy Blue Dial Watch best Reviews
FEATURED Michael Kors Watches Michael Kors Ladies Dylan Chronograph Navy Blue Dial Watch
100 meters water resistanceNavy blue dialChronograph functionClear acetate band43MM case
New materials are all the trend in watches; Michael Kors reinvents the best sellers
Click here for Availability
Click here to Read Customer Reviews
Read Full Product Specification here
Green Trendy Shopping Reviews - Best Local Deals Green Trendy
solar eclipse july 2011 in Cancer?
Question by ondia: solar eclipse july 2011 in Cancer?
What will the effects of the July 2011 eclipse be, especially for Cancer sun signs. I have had an especially difficult time during these eclipses. I was laid off, then had a miscarriage and then I discovered my mate was unfaithful and now I am fearful of what the next eclipse will bring.
I am personally a 6 degree Cancer. Thank you.
Best answer:
Answer by ♈ Marilyn ♉ ♓ Born This Wayas far as i know, eclipses will affect everyone and they bring about changes.. how it affects you will depend on your own chart, what degrees and what angle that the planets touch yours.. there's also a solar eclipse coming up on june 1st and lunar eclipse on the 15th?!
Give your answer to this question below!
Video Rating: 5 / 5
Zacks Commentary: Zacks 1 Rank Top Performers
Zacks Commentary: Zacks 1 Rank Top Performers
Article by Jim Giaquinto
Zacks Commentary: Zacks 1 Rank Top Performers - Finance
Search by Author, Title or Content
Article ContentAuthor NameArticle Title
Home
Submit Articles
Author Guidelines
Publisher Guidelines
Content Feeds
RSS Feeds
FAQ
Contact Us
The five best performing stocks on the Zacks #1 Rank List last week were: The Mosaic Company (MOS), Agrium Inc. (AGU), Massey Energy Company (MEE), NCI Building Systems, Inc. (NCS) and First Solar, Inc. (FSLR).The Mosaic Company (MOS) returned to the Zacks #1 Rank Top Performers List last week with a gain of almost 15%. Earnings estimates for the producer of concentrated phosphate and potash crop nutrients continue to move higher, especially for fiscal 2009. Expectations for the year ended May 2008 are up 3.3% in two months, but estimates for the year ending May 2009 have advanced 35%, including a rise of almost 4% in just the past seven days. The company, and its industry, moved higher last week due to high demand, especially rising corn prices.Mosaic believes its fiscal fourth-quarter results, scheduled for release late next month, will be "robust," thanks to strong demand and tight supply. The company has beaten Wall Street's quarterly earnings estimates for four consecutive quarters. In its fiscal third quarter, earnings per share of $ 1.17 topped the consensus by about 36% while easily improving on the year-ago performance. Net sales jumped 68% year over year to $ 2.1 billion.Agrium Inc. (AGU) raised its second-quarter earnings per share guidance last week, leading to an all-time high for the fertilizer company and a gain of about 12%. The company now expects EPS between $ 2.80 and $ 3 for the year, thanks to strong results from its Retail and Wholesale operations. Previously, the company was expecting $ 1.92 to $ 2.22. MOS stated that continued strong global crop prices have created unprecedented demand for crop inputs, and it expects an extended demand-driven cycle.At the time of the announcement, analysts were anticipating $ 2.50 for the quarter. Therefore, over the past seven days, estimates have jumped by 30 cents, or 12%. Expectations for the full year are up 26% in two months, including a percentage point in the past seven days. In addition, analysts expect next year's earnings to be about 26% better than this year's, which is an encouraging trend for the future.Massey Energy Company (MEE), which will soon replace OfficeMax in the S&P 500, made the Zacks #1 Rank Top Performers List for a second straight week as shares rose 11.5%. In the previous week, shares were up 13.6%. Earnings estimates for this year advanced 34% over the past two months. Furthermore, analysts expect next year's expectations to be about 41% better than this year's.Coal prices have been moving sharply higher, providing a boost to companies in the industry such as MEE. In its first quarter, earnings per share of 52 cents trounced the consensus by 62.5%, while produced coal revenue was up 4.5%. Massey Energy was very active during