The Sun is the source of energy for most of life on Earth. It derives its energy mainly from nuclear fusion in its core, converting mass to energy as protons are combined to form helium. This energy is transported to the sun's surface then released into space mainly in the form of radiant (light) energy.
Mass and energy are closely related. Due to mass–energy equivalence, any object that has mass when stationary (called rest mass) also has an equivalent amount of energy whose form is called rest energy, and any additional energy (of any form) acquired by the object above that rest energy will increase the object's total mass just as it increases its total energy. For example, after heating an object, its increase in energy could be measured as a small increase in mass, with a sensitive enough scale.
The major petroleum strikes that began the rapid growth in petroleum exploration and speculation occurred in Southeast Texas, but soon reserves were found across Texas and wells were constructed in North Texas, East Texas, and the Permian Basin in West Texas. By 1940 Texas had come to dominate U.S. production. Some historians even define the beginning of the world's Oil Age as the beginning of this era in Texas.
Fermi was well-known for his simplicity in solving problems. Whenever possible, he avoided complicated mathematics and obtained quick results based on order of magnitude estimates. Fermi also meticulously recorded his calculations in notebooks, and later used to solve many new problems that he encountered based on these earlier known problems.
Following negotiations with creditors, Chesapeake Energy applies for Chapter 11 bankruptcy in the United States. It will seek to restructure its debts in order to continue operations. The company is experiencing cash flow and liquidity issues due to low energy prices and large amounts of debt. (Reuters)
"We strongly believe that the efforts needed to combat climate change do not have to be regarded as constraints on the economy. Instead, they can be used as a lever for new, green technology." – Maud Olofsson, 2007