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n2doc

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Friday TOON Roundup 3: The Rest


Congress





Avenging Uterus





Deen







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Friday TOON Roundup 2: Court and Clowns





















Friday TOON Roundup 1: Jesus wept


























Proposed 'deflector shield' could protect astronauts from radiation

As if Star Trek didn’t already provide enough futuristic inspiration, scientists from the UK are working on an actual deflector shield that could protect astronauts from dangerous levels of radiation. And it would work in a way that's very similar to how we're protected right here on Earth.

It’s well known that a trip through open space will expose astronauts to excessive amounts of radiation. Late last month, a NASA study showed that Martian-bound astronauts would be bombarded with as much cosmic radiation as they’d get from a full-body CT scan about once a week for a year. That’s two-thirds of allowable lifetime exposure.

Coming up with a solution has not been easy. Physical radiation shielding would be unreasonably thick and heavy, making it completely impractical. There have even been calls to create a radiation shield made of poop.

But the researchers at Rutherford Appleton Laboratory (RAL) appear to have stumbled upon a rather elegant solution — one that takes the Earth’s magnetic field into account.

Down here on the surface we’re relatively immune to the Sun’s harmful rays owing to the presence of the magnetosphere. So why not recreate the same effect on a spaceship? A kind of mini-magnetosphere?


more

http://io9.com/proposed-deflector-shield-could-protect-astronauts-fr-600986396

Going, Going, Still Going? Voyager 1 at Solar System’s Edge

By KENNETH CHANG
Published: June 27, 2013
At the edge of the solar system, there are no signs that proclaim, “You are now entering interstellar space.”

NASA’s Voyager 1 spacecraft, launched more than 35 years ago and now 11.5 billion miles from where it started, is closing in on this boundary. In recent years scientists have been waiting eagerly for it to become the first artificial object to leave the solar system and enter the wider reaches of the Milky Way, which they fully expect it to do. But there has been at least one false alarm.

On Thursday, scientists reported that, no, Voyager 1 still had not reached interstellar space, but it had entered a region that no one expected and no one can yet explain, a curious zone that is almost certainly the last layer of our Sun’s empire — technically speaking, the heliosphere. Three papers published in the journal Science describe in detail the sudden and unpredicted changes encountered in the surroundings of Voyager 1, which left Earth about three months after the original “Star Wars” movie was released and is heading for the cosmos at 38,000 miles per hour.

Scientists had expected that Voyager 1 would detect two telltale signs as it passed through the heliosheath, the outermost neighborhood of the solar system, which is thought to abut the heliopause, as the actual boundary is known. Happily, the key instruments on Voyager 1, as well as those on its twin, Voyager 2, are still working after all these years, and its nuclear power source will last until at least 2020.

more

http://www.nytimes.com/2013/06/28/science/space/going-going-still-going-voyager-1-at-solar-systems-edge.html

Toon: New Texas Symbol

Inside The Most Expensive Science Experiment Ever (ITER Fusion)

By Daniel Clery



Some people have spent their whole working lives researching fusion and then retired feeling bitter at what they see as a wasted career. But that hasn’t stopped new recruits joining the effort every year: optimistic young graduates keen to get to grips with a complicated scientific problem that has real implications for the world. Their numbers have been increasing in recent years, perhaps motivated by two factors: there is a new machine under construction, a huge global effort that may finally show that fusion can be a net producer of energy; and the need for fusion has never been greater, considering the twin threats of dwindling oil supplies and climate change.

The new machine is the International Thermonuclear Experimental Reactor, or simply ITER (pronounced ‘eater’). Many machines over the past 60 years have been billed as ‘the one’ that will make the big breakthrough, only to stumble before getting there. But considering how close JET, its direct predecessor, got to break-even, ITER has to have a good chance. ITER is not a power station, it won’t be connected to the grid and won’t even generate any electricity, but its designers are aiming to go far beyond break-even and spark enough fusion reactions to produce 10 times as much heat as that pumped in to make it work. To get there requires a reactor of epic proportions. The building containing the reactor will be 60m tall and extend 13m underground--altogether taller than the Arc de Triomphe. The reactor inside will weigh 23,000 tonnes--continuing the Parisian theme, that’s more than three Eiffel Towers.

At the time of writing, workers at the ITER site in Cadarache, southern France, are laying foundations, erecting buildings, installing cables and generally preparing the ground. In factories around the world the various components that will make up the reactor are being built, ready to be shipped to France and assembled on site. The scale and the quantities are prodigious. In six different ITER member countries factories are churning out niobium-tin superconducting wires for the reactor’s magnets. When finished, they will have made 80,000km of wire, enough to wrap around the equator twice. The giant D-shaped coils of wire that are the electromagnets used to contain the plasma are each 14m tall and weigh 360 tonnes, as much as a fully laden jumbo jet. ITER needs 18 of these magnets. Perhaps the most mindboggling statistic about ITER, and one of the reasons it is being built by an international collaboration, is its cost: somewhere between €13 billion and €16 billion. That makes it the most expensive science experiment ever built--twice as expensive as the Large Hadron Collider at CERN.

That huge sum of money is, for the nations involved, a gamble against a future in which access to energy will become an issue of national security. Most agree that oil production is going to decline sharply during this century. There is still plenty of coal around but burning it in large quantities increases the risk of catastrophic climate change. That doesn’t leave many options for the world’s future energy supplies. Conventional nuclear power makes people uneasy for many reasons, including safety, the problems of disposing of waste, nuclear proliferation and terrorism.


more
http://www.popsci.com/science/article/2013-06/piece-sun

Heat Wave May Threaten World’s Hottest Temp. Record

By Andrew Freedman

A brutal and potentially historic heat wave is in store for the West as parts of Nevada, Arizona and California may get dangerously hot temperatures starting Thursday and lasting through next week. In fact, by the end of the heat wave, we may see a record tied or broken for the hottest temperature ever recorded on Earth.

The furnace-like heat is coming courtesy of a “stuck” weather pattern that is setting up across the U.S. and Canada. By midweek next week, the jet stream — a fast-moving river of air at airliner altitudes that is responsible for steering weather systems — will form the shape of a massive, slithering snake with what meteorologists refer to as a deep “ridge” across the Western states, and an equally deep trough seting up across the Central and Eastern states.



All-time records are likely to be threatened in normally hot places — including Death Valley, Calif., which holds the record for the highest reliably recorded air temperature on Earth at 134°F. That mark was set on July 10, 1913, and with forecast highs between 126°F to 129°F this weekend, that record could be threatened. The last time Death Valley recorded a temperature at or above 130°F was in 1913.

Las Vegas and Phoenix, two cities well-known for their hot and dry summers, are also predicted to approach record territory. Last Vegas’ all-time high temperature record is 117°F and Phoenix’s high is 122°F. Excessive heat warnings are in effect in both cities from Friday through Monday.

more

http://www.climatecentral.org/news/heat-wave-to-threaten-worlds-hottest-temperature-record-16161

George Takei: A defeat for DOMA — and the end of ‘ick’

By George Takei,

Forty-four years nearly to the day after drag queens stood their ground against a police raid on the Stonewall Inn, sparking rioting in New York City and marking the beginning of America’s gay rights movement, our nation’s highest court at last held that a key section of the Defense of Marriage Act is unconstitutional. Amazingly, since Stonewall, the question of LGBT rights has evolved from whether homosexuals should have any place in our society to whether gay and lesbian couples should be accorded equal marital stature.

Whenever one group discriminates against another — keeping its members out of a club, a public facility or an institution — it often boils down to a visceral, negative response to something unfamiliar. I call this the “ick.” Indeed, the “ick” is often at the base of the politics of exclusion. Just this March, for example, a young woman at an anti-same-sex-marriage rally in Washington was asked to write down, in her own words, why she was there. Her answer: “I can’t see myself being with a woman. Eww.”

Frankly, as a gay man, I can’t see myself being with one, either. But it’s usually not gays who write the laws. If this woman were in Congress, her personal discomfort might infect her thinking — and her lawmaking. Gays kissing?Ick.

The Supreme Court may be the ultimate interpreter of the rules, but it is still the court of public opinion that matters. And public opinion has shifted — 51 percent of Americans now favor same-sex marriage, according to a recent Pew Research Center poll, and 42 percent oppose it. Reflecting this slim majority, Wednesday’s 5 to 4 ruling made clear that “ick” is not a proper basis for constitutional jurisprudence. Justice Anthony Kennedy, in his opinion, warned against this specifically, noting that when “determining whether a law is motived by an improper animus . . . ‘discriminations of an unusual character’ especially require careful consideration.” Kennedy was not prepared to allow the “ick” to remain law, knowing that the result is often embarrassing when judged by history.

more

http://www.washingtonpost.com/opinions/george-takei-a-defeat-for-doma--and-the-end-of-ick/2013/06/27/d3c986dc-dd10-11e2-9218-bc2ac7cd44e2_story.html

NASA rocket engine runs 5+ years

By JAKE ELLISON, SEATTLEPI.COM STAFF
Updated 4:54 pm, Wednesday, June 26, 2013



It's been blasting away since early 2008, a constant thrust for over 48,000 hours, and it's still ready for more, NASA says of its advance ion propulsion engine.

"We will voluntarily terminate this test at the end of this month, with the thruster fully operational. Life and performance have exceeded the requirements for any anticipated science mission," said Michael J. Patterson, principal investigator for NEXT at Glenn, in a press release.

The agency says:

The thruster was developed under NASA's Evolutionary Xenon Thruster (NEXT) Project at NASA's Glenn Research Center in Cleveland. Glenn manufactured the test engine's core ionization chamber. Aerojet Rocketdyne of Sacramento, Calif., designed and built the ion acceleration assembly. ...

The NEXT engine is a type of solar electric propulsion in which thruster systems use the electricity generated by the spacecraft's solar panel to accelerate the xenon propellant to speeds of up to 90,000 mph. This provides a dramatic improvement in performance compared to conventional chemical rocket engines.



http://www.seattlepi.com/national/article/NASA-rocket-engine-runs-5-years-still-not-4623930.php
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