Lake Lanier, the water source that serves a third of Georgia's residents, only has a 4 month's supply of water. Forecasters predict the drought could last months, and residents should look for news ways to conserve.

Atlanta Mayor Shirley Franklin says, the city has cut water use by not watering parks. She says maintaining water supplies for drinking and fighting fires is the primary concern. Atlanta commissioner for the Department of Watershed Management, Rob Hunter says Lake Lanier has a 121 day supply of water. He says reducing consumption is key. He offered residents several suggestions: take shorter showers, repair leaky faucets and pipes, and cut outdoor water usage. [More]

Labels: physics, science, weather

17 But to a physicist there is no such thing as nothing. Empty space is instead filled with pairs of particles and antiparticles, called virtual particles, that quickly form and then, in accordance with the law of energy conservation, annihilate each other in about 10-25 second.

18 So Aristotle was right all along.

19 These virtual particles popping in and out of existence create energy. In fact, according to quantum mechanics, the energy contained in all the power plants and nuclear weapons in the world doesn’t equal the theoretical energy contained in the empty spaces between these words.

Labels: fun, physics

Say you woke up one day and your bed was gone. Your room, too. Gone. It's all gone. You wake up in an inky void. Not even a star. Okay, yes, it's a dumb idea, but just go with it. Now say you want to know if you move or not. Are you held fast in one spot? Or do you, say, list off to the left some? What I want to ask you is: Can you find out? Hell no. You can see that, sure. You don't need me to tell you. To move, you have to move to or away from ... well, from what? You'd have to say that you don't even get to use a word like "move" when you are the only body in that void. Sure. Okay. Now, let's add the bed back. Your bed is with you in the void. But not for long -- it goes away from you. You don't have any way to get it back, so you just let it go. But so now we have a body in the void with you. So does the bed move, or do you move? Or both? Well, you can see as well as I that it can go any way you like. Flip a coin. Who's to say? It's best to just say that you move away from the bed, and that the bed goes away from you. No one can say who's held fast and who isn't. [More]

Labels: fun, physics

The case of the poisoned former KGB agent took a bizarre twist when British Airways said that traces of radiation had been detected Wednesday on jets that flew between London and Moscow, establishing a possible Russian link and indicating that more than 30,000 people may have been exposed to radiation.

The airline said tests found "very low traces" of radioactivity on one of three Boeing 767s that flew between London and Moscow days before Alexander Litvinenko fell ill from the radioactive poison that doctors say killed him. [More]

¹⁰Po

Polonium-210 is an alpha emitter that has a half-life of 138.376 days. A milligram of ²¹⁰Po emits as many alpha particles as 5 grams of radium. A great deal of energy is released by its decay with half a gram quickly reaching a temperature above 750 K. A few curies (1 curie equals 37 gigabecquerels) of ²¹⁰Po emit a blue glow which is caused by excitation of surrounding air. A single gram of ²¹⁰Po generates 140 watts of power.^[9] Because it emits many alpha particles, which are stopped within a very short distance in dense media and release their energy, ²¹⁰Po has been used as a lightweight heat source to power thermoelectric cells in artificial satellites. A ²¹⁰Po heat source was also used in each of the Lunokhod rovers deployed on the surface of the Moon, to keep their internal components warm during the lunar nights. Some anti-static brushes contain up to 500 microcuries of ²¹⁰Po as a source of charged particles for neutralizing static electricity in materials like photographic film.^[10] The majority of the time ²¹⁰Po decays only by emission of an alpha particle, not by emission of an alpha particle and a gamma ray. About one in a 100000 decays results in the emission of a gamma ray[4], this low gamma ray production rate makes it more difficult to find and identify this isotope. Rather than gamma ray spectroscopy, alpha spectroscopy will be the best method of measuring this isotope.

Labels: physics, Russia