Gravitational lens A light source passes behind a gravitational lens (point mass placed in the center of the image). The aqua circle is the light source as it would be seen if there was no lens, white spots are the multiple images (or Einstein ring) of the source. A gravitational lens is a distribution of matter (such as a cluster of galaxies) between a distant light source and an observer, that is capable of bending the light from the source as the light travels towards the observer. This effect is known as gravitational lensing, and the amount of bending is one of the predictions of Albert Einstein's general theory of relativity. (Classical physics also predicts the bending of light, but only half that predicted by general relativity.) Although Einstein made unpublished calculations on the subject in 1912, Orest Khvolson (1924) and Frantisek Link (1936) are generally credited with being the first to discuss the effect in print. Description 1. 2. 3. History Notes
Wolfram|Alpha: Computational Knowledge Engine Fabrice Leclerc: Top #tweeted story in #bio... MiGUi 12 Letters That Didn’t Make the Alphabet You know the alphabet. It’s one of the first things you’re taught in school. But did you know that they’re not teaching you all of the alphabet? 1. Have you ever seen a place that calls itself “ye olde whatever”? Thorn, which was pronounced exactly like the "th" in its name, is actually still around today in Icelandic. 2. Another holdover from the Futhark runic alphabet, wynn was adapted to the Latin alphabet because it didn’t have a letter that quite fit the “w” sound that was common in English. Over time, though, the idea of sticking two u’s together actually became quite popular, enough so that they literally became stuck together and became the letter W (which, you’ll notice, is actually two V’s). 3. Yogh stood for a sort of throaty noise that was common in Middle English words that sounded like the "ch" in "Bach" or Scottish "loch." French scholars weren’t fans of our weird non-Latin letters and started replacing all instances of yogh with “gh” in their texts. 4. 5. 6. 7. 8. 9. 10.
Gravitational microlensing Gravitational microlensing is an astronomical phenomenon due to the gravitational lens effect. It can be used to detect objects ranging from the mass of a planet to the mass of a star, regardless of the light they emit. Typically, astronomers can only detect bright objects that emit lots of light (stars) or large objects that block background light (clouds of gas and dust). These objects make up only a tiny fraction of the mass of a galaxy. Microlensing allows the study of objects that emit little or no light. When a distant star or quasar gets sufficiently aligned with a massive compact foreground object, the bending of light due to its gravitational field, as discussed by Einstein in 1915, leads to two distorted unresolved images resulting in an observable magnification. Since microlensing observations do not rely on radiation received from the lens object, this effect therefore allows astronomers to study massive objects no matter how faint. How it works History . . . . .
National Geographic Magazine DailyScan : RT @rnomics: Top #tweeted... Francis (th)E mule Science's News Fairy Tales For 20-Somethings Tumblr Reveals The Truth About Growing Up Sleeping Beauty, Snow White, Rumpelstiltskin, Cinderella, Little Red Riding Hood. Most children grow up reading (and watching the Disney versions) of these fairy tales. And somehow, even years after, they still manage to hold a special place in our collective imaginations -- just look at the number of fairy tale-themed movies and TV shows for adults that have cropped up over the past few years ("Snow White and the Huntsman," "Grimm," "Once Upon A Time" and "Mirror, Mirror," just to name a few). Now Tim Manley, a 27-year-old New York City high school teacher, has reimagined many of these classic stories ... in the voice of a 20-something, Millennial urbanite. The results, published on his Tumblr, "Fairy Tales For 20-Somethings," satirize the mindset of that demographic pretty brilliantly. Snow White dreams of Ryan Gosling, Rumpelstiltskin starts thinking about his reproductive urges, the tortoise meets the hare for a caffeine break, and Chicken Little discovers hot yoga. "Rumpelstiltskin"
Physics World reveals its top 10 breakthroughs for 2011 The two physics stories that dominated the news in 2011 were questions rather than solid scientific results, namely "Do neutrinos travel faster than light?" and "Has the Higgs boson been found?". However, there have also been some fantastic bona fide research discoveries over the last 12 months, which made it difficult to decide on the Physics World 2011 Breakthrough of the Year. But after much debate among the Physics World editorial team, this year's honour goes to Aephraim Steinberg and colleagues from the University of Toronto in Canada for their experimental work on the fundamentals of quantum mechanics. Using an emerging technique called "weak measurement", the team is the first to track the average paths of single photons passing through a Young's double-slit experiment – something that Steinberg says physicists had been "brainwashed" into thinking is impossible. We have also awarded nine runners-up (see below). 1st place: Shifting the morals of quantum measurement
Victorian Infographics A time table indicating the difference in time between the principal cities of the World and also showing their air-line distance from Washington. IN: 'Mitchell's New General Atlas, Containing Maps Of The Various Countries Of The World, Plans Of Cities, Etc., Embraced In Ninety-Three Quarto Maps, Forming A Series Of One Hundred and Forty-seven Maps and Plans, Together With Valuable Statistical Tables..' by Samuel Augustus Mitchell Jr, 1883; published in Philadelphia by WM Bradley. Tableau d'Astronomie et de Sphère IN: 'Atlas Universel d'Histoire et de Geographie Anciennes et Modernes, de Mythologie, des Religions, d'Astronomie, de Physique, de Geologie, de Histoire Naturelle, de Grammaire, de Rhetorique..' by Henri Duval, 1834; published in Paris by L Houbloup. Tableau d'Astronomie et de Sphère [detail] The Solar System. IN: 'General Atlas Of The World: Containing Upwards Of Seventy Maps. Northern Celestial Hemisphere. IN: 'General Atlas Of The World: Containing Upwards Of Seventy Maps...