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Comment Actually, 0.043 c (Score 5, Informative) 711

I believe your math is wrong. U235 releases 202.5 MeV per atom undergoing fission, so that means 1 kg can generate 83.14 TJ from fission. Assuming 100% efficiency, a massless drive, and no mass loss from propellants, that means there is enough energy from fission to reach a velocity of 0.043 c relative to the rest frame.

dE = (m - m') c^2 = m' c^2 (gamma - 1) => m' c^2 = m c^2 (1 - dE/(m c^2)) = m c^2 (1 - rho)

rho = dE/(m c^2) = 83.14 TJ / 89.88 PJ = 9.25e-4

rho = (1 - rho) (gamma - 1) => gamma = 1/(1 - rho) = 1/sqrt(1 - beta^2)

(1 - rho)^2 = 1 - beta^2 => beta^2 = rho (2 - rho) = 1.85e-3

beta = sqrt(rho (2 - rho)) = 0.0430

Comment Re:Chrome Remote Desktop (Score 1) 418

After my parents' Program Files were deleted when they installed a Flash update (curse you Adobe for bundling McAfee), I rebuilt their machine such that I would be the only user with admin privileges. For software updates, I use Chrome Remote Desktop because it's easy, secure, and most importantly, free. If they need to run a program that needs admin privileges (like TurboTax) I setup a special shortcut for them using RunasRob that will run the program as an admin without needing my password.

Do Tech Entrepreneurs Need To Know How To Code? 202

An anonymous reader writes "Learning to write code has become something of a trendy thing to do. New York City Mayor Michael Bloomberg has said he intends to learn code this year. Estonia has recently announced a scheme with the aim of getting every 6-year-old in the Baltic state to learn programming skills. The demand has spawned a number of start-ups offering coding lessons. General Assembly, which teaches off-line courses, has recently opened up in London and is recruiting ahead of a launch in Berlin. On-line education site Codecademy landed $10 million to expand from its home base in New York. Zach Simms, the 22-year-old co-founder, said in an earlier interview with The Wall Street Journal that not everyone has to learn to code, but everybody 'needs to learn the notions of algorithms, realizing what you can use code for.' But do they?"

Comment Re:This guy is an idiot (Score 1) 305

Asimov was a writer, who wrote fiction books. He didn't understand technology at all

Asimov wrote more than just fiction, he wrote dozens of science books on topics including: astronomy, biology, chemistry, classical physics, and subatomic physics.

Comment Re:Pretty simple explanation... (Score 1) 841

The claim is that writing can't be taught on an industrial scale but science can be.

No, these classes are taught this way out of necessity. If a grad student wants a physics degree, (s)he must do research. To this end, a typical physics grad student will TA for just a few semesters until (s)he gets a research project. This is a full time job. There just aren't enough incoming grad students to fill more teaching positions. I suspect it's similar for all the sciences.

I don't know what it's like for English grad students, but I suspect that it's the exact opposite. As far as I'm aware, English majors don't need to do the same kind of time intensive research. I suspect that English grad students will teach classes throughout their higher education.

Thus, even if there are the same number of incoming physics and English grad students, I suspect that there will be 4-6 times as many English majors available for teaching.


Submission + - Studying the Impact of Lost Shipping Containers ( 3

swellconvivialguy writes: Looking at a picture of the world’s largest container ship it’s easy to visualize how 10,000 containers fall overboard from these vessels every year. Now scientists from the Monterey Bay Aquarium Research Institute are undertaking the Lost Container Cruise, an attempt to gauge the effects of shipping containers lost at sea by studying a tire-filled container, which marine biologists discovered in the Monterey Bay National Marine Sanctuary. ( The research is being funded by a multi-million dollar settlement with the operators of the Med Taipei, the ship that lost the cargo.) The work is not unlike studying a deep water shipwreck: Use robotic submarine to take pictures and collect sediment samples; repeat.

Submission + - Edge of Solar System Filled with Bubbles (

cultiv8 writes: "The edge of our solar system is filled with a turbulent sea of magnetic bubbles, according to new NASA research.

Scientists made the discovery by using a new computer model, which is based on data from NASA's twin Voyager probes. The unmanned Voyager 1 and Voyager 2, which launched in 1977, are plying the outer reaches of our solar system, a region known as the heliosheath.

The new discovery suggests that researchers will need to revise their views about the solar system's edge, NASA officials said. A more detailed picture of this region is key to our understanding of how fast-moving particles known as cosmic rays are spawned, and how they reach near-Earth space."


Submission + - World's largest OLED globe from Mitsubishi (

cylonlover writes: Mitsubishi Electric will unveil a huge, 19.7 foot (6 m) wide OLED globe at Tokyo's National Museum of Emerging Science and Innovation on June 11. Billed as the world's first large-scale spherical OLED screen, "Geo-Cosmos" is made up of an aluminum frame covered with 10,362 tiny OLED panels, each measuring 3.7 x 3.7 inches. The sphere will display images of clouds and other views of the Earth coming from a meteorological satellite as it hangs almost 60 feet (18 m) above the museum floor.

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