But in recent years, print reference books have been almost completely overtaken by the Internet and its vast spread of resources, including specialized Web sites and the hugely popular — and free — online encyclopedia Wikipedia. Since it was started 11 years ago, Wikipedia has moved a long way toward replacing the authority of experts with the wisdom of the crowds.
The site is now written and edited by tens of thousands of contributors around the world, and it has been gradually accepted as a largely accurate and comprehensive source, even by many scholars and academics. Wikipedia also regularly meets the 21st-century mandate of providing instantly updated material. And it has nearly four million articles in English, including some on pop culture topics that would not be considered worthy of a mention in the Encyclopaedia Britannica.
Cauz said. We cannot deal with every single cartoon character, we cannot deal with every love life of every celebrity. But we need to have an alternative where facts really matter. The study said that out of 42 competing entries, Wikipedia made an average of four errors in each article, and Britannica three.
It is frequently bought by embassies, libraries and research institutions, and by well-educated, upscale consumers who felt an attachment to the set of bound volumes.
Only 8, sets of the edition have been sold, and the remaining 4, have been stored in a warehouse until they are bought. Sales of the Britannica peaked in , when , sets were sold in the United States. This gorgeous volume is a modern classic, and will inspire curiosity and delight in every reader.
Students, teachers, and librarians can find fast facts combined with the quality and accuracy that have made Britannica the brand to trust. A tool for both the classroom and the library, no other desk reference can compare. Floating in this vast, dark void are all sorts of different objects, which astronomers call celestial bodies. They range from grains of dust to planets, stars, and galaxies. Our Solar System includes a star the Sun and a large family of planets and moons that formed from the same cloud of gas that gave birth to the Sun.
In recent years, planets have been seen around hundreds of other stars, showing that our Solar System may be one of billions in our galaxy. The Universe probably has no center or outer edge. Only a fraction of it—the observable Universe—is visible to us. The whole Universe may be vastly bigger than this, perhaps infinitely so. This is hard to visualize, so scientists use the metaphor of a two-dimensional rubber sheet to explain the idea.
The mass of the Universe could bend this rubber sheet in one of three ways, depending on how densely packed with matter the Universe is.
0コメント