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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


Genetic Convergent Evolution: Stunning Gene Similarities Among Diverse Animals 164

Toe, The writes "It has long been understood that completely different animals can end up with very similar traits (convergent evolution), and even that genes can converge. But a new study shows an unbelievable level of convergence among entire groups of genes. The study shows that animals as diverse as bats and dolphins, which independently developed echolocation, converge in nearly 200 different genomic regions concentrated in several 'hearing genes.' The implications are rather deep, if you think about it, delving into interesting limitations on diversity or insights into the potential of DNA. And perhaps more importantly, this finding goes a long way toward explaining why almost aliens in the universe look surprisingly identical to humans (though still doesn't explain why they all speak English)."

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.

X-Ray Laser For Creating Supercharged Particles 55

William Robinson writes "Scientists have found way to use X-Ray Lasers to create supercharged particles. The specific tuning of the laser's properties can cause atoms and molecules to resonate. The resonance excites the atoms and causes them to shake off electrons at a rate that otherwise would require higher energies. This could be used to create highly charged plasma."

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.


ISS Nearly Clobbered By Space Debris 131

erice writes "A chuck of space debris came within 335 meters of the space station, forcing the crews to head to their escape capsules and prepare for emergency evacuation to Earth. '[NASA's] Associate Administrator for Space Operations, Bill Gerstenmaier, said it was the closest a debris object had ever come to the station. An analysis was now underway to try to understand its origin, he added.'"

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.

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