कार्दाशेव स्केल : सभ्यता के विकास का पैमाना

विज्ञान विश्व

1964 मे कार्दाशेव ने किसी परग्रही सभ्यता के तकनीकी विकास की क्षमता को मापने के लिये एक पैमाने को प्रस्तावित किया।

रशियन खगोल विज्ञानी निकोलाइ कार्दाशेव के अनुसार सभ्यता के विकास के विभिन्न चरणो को ऊर्जा की खपत के अनुसार श्रेणीबद्ध लिया जा सकता है। इन चरणो के आधार पर परग्रही सभ्यताओं का वर्गीकरण किया जा सकता है। भौतिकी के नियमो के अनुसार उन्होने संभव सभ्यताओं को तीन प्रकार मे बांटा, वर्ग I, वर्ग II तथा वर्ग III सभ्यतायें।

प्रसिद्ध रूसी खगोलभौतिक वैज्ञानिक निकोलाई कार्दाशेव ने इस पैमाने को कार्दाशेव स्केल नाम दिया।


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BOOK: Debating Darwin

The Dispersal of Darwin

A new book pits one Darwin expert against another in their views on what had more influence on Darwin: the social context of Industrial Revolution England or the German romantics.


Robert J. Richards and Michael Ruse, Debating Darwin (Chicago: University of Chicago Press, 2016), 320 pp.

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Publisher’s description Charles Darwin is easily the most famous scientist of the modern age, and his theory of evolution is constantly referenced in many contexts by scientists and nonscientists alike. And yet, despite how frequently his ideas are evoked, there remains a surprising amount we don’t know about the father of modern evolutionary thinking, his intellectual roots, and the science he produced. Debating Darwin seeks to change that, bringing together two leading Darwin scholars—Robert J. Richards and Michael Ruse—to engage in a spirited and insightful dialogue, offering their interpretations of Darwin…

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Bay: A Large body of Water

The bay at San Sebastián, Spain

A bay is a large body of water connected to an ocean or sea formed by an inlet of land due to the surrounding land blocking some waves and often reducing winds. Bays also exist in in-land environments as an inlet to any larger body of water, such as a lake or pond, or the estuary of a river, such as those found in and around the Great Lakes of North America, or in the estuary of the Parramatta River in Australia. A large bay may be called a gulf, a sea, a sound, or a bight. A cove is a circular or oval coastal inlet with a narrow entrance; some coves may be referred to as bays. A fjord is a particularly steep bay shaped by glacial activity.

Bays remained significant in the history of human settlement because they can provide a safe place for fishing. Later they were important in the development of sea trade as the safe anchorage they provide encouraged their selection as ports. Any bay may contain fish and other sea creatures or be adjacent to other bays. For example, James Bay is adjacent to Hudson Bay. Large bays, such as the Bay of Bengal and the Hudson Bay, have varied marine geology.

Formation of Bay

There are various ways that bays can be created. The largest bays have developed as a result of continental drift. As the super-continent Gondwana broke up along curved and indented fault lines, the continents moved apart and the world’s largest bays formed. These include the Gulf of Guinea, Persian Gulf, Gulf of Alaska, Gulf of Mexico and the Bay of Bengal which is the largest bay in the world.

Another way bays are formed is via glacial and river erosion. If formed by glaciers a bay is known as a fjord. Rias are created by rivers and are characterised by more gradual slopes. Most gulf and bays are formed by the folding of the earth’s crust as well as coastal erosion due to waves and currents. Currents can make waves more constant, while soft rocks will allow erosion to have a stronger effect. Any hard rock is eroded less quickly, leaving headlands. The Gulf of California is an example of a bay created by the geological process of folding.

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Don’t Be Afraid

Orlando Espinosa

Don’t be afraid of moving forward, be afraid of standing still!

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