Tuesday, July 2, 2013
NASA to flip ion engine's 'OFF' switch after brilliant 5.5 year burn
NASA's Evolutionary Xenon Thruster (NEXT), an ion-propulsion engine that has been firing continuously for five and one-half years, is due to be shut down at the end of this month.
The world's record holder for ion-propulsion longevity: NASA's NEXT (click to enlarge)
Despite that speedy ejection, the thrust produced by the engine is quite low when compared to the sturm und drang of conventional chemical rocketry – so low, in fact, that it wouldn't be enough to even move the engine itself, let alone any payload, here on Earth. In the vacuum of space, however, the constant acceleration provided by the NEXT engine – or its descendants – could eventually propel a spacecraft at speeds over 200,000 mph, NASA says.
Perhaps more importantly, ion-propulsion engines are both highly efficient, fuel-wise, and can be operated continuously for a long, long time – even longer than the five and a half years of NEXT's operations. During its entire test run, NEXT used a mere 870 kilograms of xenon to produce a total amount of thrust that would require, NASA says, the equivalent of 10,000 kilograms of conventional propellant.
It's not difficult to see the advantages of ion propulsion once a craft has slipped the surly bonds of earth. In fact, "advantages" might be too weak a word. If mankind ever wants to explore deep, deep space, ion propulsion and other solar-electric thrusters might better be described as a necessity – which is why work on ion propulsion has been underway at the Glenn Research Center since the 1950s.
But that work will now go on without NEXT. As principal investigator Patterson said, NEXT will be shut down at the end of this month. So long, indefatigable ion-spitter, and thanks for all the thrust.
The world's record holder for ion-propulsion longevity: NASA's NEXT (click to enlarge)
"We will voluntarily terminate this test at the end of this month, with the thruster fully operational," said NEXT's principal investigator Michael Patterson in a statement. "Life and performance have exceeded the requirements for any anticipated science mission."
Considering that the NEXT thruster has run steadily for over 48,000 hours, we would say that Patterson and his team have contributed mightily to NASA's reputation of building devices with life spans that exceed expectations. The Martian mini-rover Opportunity, for one excellent example, was originally designed for a 90-day mission, but celebrated its ninth anniversary this January and set a new NASA distance record in May.
For over 2,000 days, the ion propulsion NEXT engine has been humming along in a high vacuum test chamber at NASA's Glenn Research Center in Cleveland, Ohio, bombarding inert, colorless, odorless, tasteless (not in the Kardashian sense) xenon gas with electrons and ionizing it.
That ionized plasma is created in an area of the engine with a highly positive charge, and the ions are thus attracted to the highly negative charge of the engine's "accelerator grid," which spits them out into space – or, in NEXT's case, the test chamber – at speeds of up to 90,000 mph.
Positively charged ions being sucked through NEXT's negatively charged accelerator grid (click to enlarge)
Considering that the NEXT thruster has run steadily for over 48,000 hours, we would say that Patterson and his team have contributed mightily to NASA's reputation of building devices with life spans that exceed expectations. The Martian mini-rover Opportunity, for one excellent example, was originally designed for a 90-day mission, but celebrated its ninth anniversary this January and set a new NASA distance record in May.
For over 2,000 days, the ion propulsion NEXT engine has been humming along in a high vacuum test chamber at NASA's Glenn Research Center in Cleveland, Ohio, bombarding inert, colorless, odorless, tasteless (not in the Kardashian sense) xenon gas with electrons and ionizing it.
That ionized plasma is created in an area of the engine with a highly positive charge, and the ions are thus attracted to the highly negative charge of the engine's "accelerator grid," which spits them out into space – or, in NEXT's case, the test chamber – at speeds of up to 90,000 mph.
Positively charged ions being sucked through NEXT's negatively charged accelerator grid (click to enlarge)
Despite that speedy ejection, the thrust produced by the engine is quite low when compared to the sturm und drang of conventional chemical rocketry – so low, in fact, that it wouldn't be enough to even move the engine itself, let alone any payload, here on Earth. In the vacuum of space, however, the constant acceleration provided by the NEXT engine – or its descendants – could eventually propel a spacecraft at speeds over 200,000 mph, NASA says.
Perhaps more importantly, ion-propulsion engines are both highly efficient, fuel-wise, and can be operated continuously for a long, long time – even longer than the five and a half years of NEXT's operations. During its entire test run, NEXT used a mere 870 kilograms of xenon to produce a total amount of thrust that would require, NASA says, the equivalent of 10,000 kilograms of conventional propellant.
It's not difficult to see the advantages of ion propulsion once a craft has slipped the surly bonds of earth. In fact, "advantages" might be too weak a word. If mankind ever wants to explore deep, deep space, ion propulsion and other solar-electric thrusters might better be described as a necessity – which is why work on ion propulsion has been underway at the Glenn Research Center since the 1950s.
But that work will now go on without NEXT. As principal investigator Patterson said, NEXT will be shut down at the end of this month. So long, indefatigable ion-spitter, and thanks for all the thrust.
Monday, July 1, 2013
This is believed to be the last picture taken of Titanic before her sinking
Morgan Robertson Writes About the Titanic... 14 Years Early
A hundred years before James Cameron turned douchebaggery into an art form at the Oscars, American author Morgan Robertson wrote a shitty book called Futility, or the Wreck of the Titan, about the sinking of an "unsinkable" ocean liner. When you see the cover, you figure you're pretty clearly looking at a fictionalized version of the Titanic story.
No surprise there; it's a story that's been told over and over (there were 13 Titanic movies before Cameron's, including one by the Nazis) but Robertson's book was first.
Where it Gets Weird:
He was so eager to be first, apparently, that he didn't bother to wait for the Titanic to actually sink before writing about it. The Wreck of the Titan was published in 1898, 14 years before RMS Titanic was even finished being [cheaply] built.
The similarities between Robertson's work and the Titanic disaster are so astounding that one has to imagine if White Star Line built Titanic to Robertson's specs as a dare. The Titan was described as "the largest craft afloat and the greatest of the works of men," "equal to that of a first class hotel," and, of course, "unsinkable".
Both ships were British-owned steel vessels, both around 800 feet long and sank after hitting an iceberg in the North Atlantic, in April, "around midnight." Sound like enough to keep you up at night? Maybe that's why Robertson republished the book in 1912 just in case enough people didn't know that he wrote it.
And you thought this guy was an ass.
Where it Gets Even Weirder:
While the novel does bear some curious coincidences with the Titanic disaster, there are quite a few things that Robertson got flat wrong. For one, the Titanic did not crash into an iceberg "400 miles from Newfoundland" at 25 knots. It crashed into an iceberg 400 miles from Newfoundland at 22.5 knots.
Wait, what the fuck? That's one hell of a lucky guess!
What 41.1 million square miles looks like.
But maybe the weirdest thing about Titan were points that had nothing to do with the story, but check out after numerous inquires and expeditions to the Titanic wreck site.
For one, both the Titan and the Titanic had too few lifeboats to accommodate every passenger on board; the Titan carrying "as few as the law allowed." While Robertson decided to be generous and include four lifeboats more on his ship than Titanic, it's an odd point to bring up when you consider that lifeboats had nothing to do with the fucking story. When Titan hit the iceberg (starboard bow, naturally), the ship sank immediately, making the point made about lifeboats inconsequential. Why the fuck mention this?!
It'd be like HAL 9000 addressing the danger posed by O-rings at low temperature decades before the Challenger disaster.
WARNING - Graphic Video Of Beheading Of Catholic Priest By Obama Backed Syrians
This should make it clear to Christians around the world what jihadists are about. Make no mistake. Catholics and Christians around the globe are under dire threat, particularly from the spread of militant Islam. Until the threat is recognized and taken seriously, martyrdoms like this will continue.
Very Graphic Video, do not click if you are not prepared to see raw 8th century savagery:
The Biggest Problem In The U.S./World is....Wait For It.... Coal.
In March of 2011, then Energy Secretary Steven Chu appeared on Fox News Sunday and host Chris Wallace asked him about his desire in 2008 for Americans to punitively pay more at the pump in order to wean them off of gasoline. Shockingly, Chu did not walk back his comments as he has attempted to do in the past. In fact, he embraced the strategy noting that his focus is to ease the pain felt by his energy policies by forcing automakers to make more fuel-efficient automobiles. Forcing Auto makers to make cars that Americans do not want. Our freedom to choose the car of our choice will be restricted and regulated by government.
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