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Space

Submission + - Thunderstorms proven to create antimatter 1 1

radioweather writes: Scientists using NASA's Fermi Gamma-ray Space Telescope have detected beams of antimatter from thunderstorms in the form of positrons hurled into space. Scientists think the antimatter particles were formed in a terrestrial gamma-ray flash (TGF), a brief burst produced inside thunderstorms and shown to be associated with lightning. "These signals are the first direct evidence that thunderstorms make antimatter particle beams," said Michael Briggs, a member of Fermi's Gamma-ray Burst Monitor (GBM) team. He presented the findings at a news briefing at the American Astronomical Society meeting in Seattle. As the late, great, Johnny Carson of the Tonight Show used to say, “That is some weird, wild, stuff“.
Space

On Fourth Launch Attempt, SpaceX Falcon 1 Reaches Orbit 518 518

xp65 writes with the just-announced success of Elon Musk's SpaceX's long efforts to reach orbit with a privately-developed launching craft: "T+0:08:21 Falcon 1 reached orbital velocity, 5200 m/s Nominal Second stage cut off (SECO) — Falcon 1 has made history as the first privately developed liquid fueled launch vehicle to achieve earth orbit!" dbullard adds "This was a completely new vehicle — it's not using any previously developed hardware. All developed from scratch. No government supplied hardware, Russian engines, or old ICBM motors. My hat's off to the employees of Space X — all 550 of them. (Note — no 'cast of thousands,' just 550). They've got video of the entire launch."

Comment Re:Not the end of the world... (Score 5, Informative) 293 293

Can one of you physicists tell me how 4.5 Kelvin is different from 2 Kelvin, operationally?

The magnets they use to shape and steer the beam require about 12,000 amps, so they use superconductors. Between 2K and 4.5K, the superconductor undergoes a phase change and becomes non-superconducting, and the resistance goes from zero to not zero all of a sudden. The 12,000 amps suddenly produces an incredible amount of heat (P=I^2R) which drastically increases the pressure from the liquid He. That much pressure means the He needs to escape (violently), causing all sorts of trouble. It's called a 'quench.'

You are in a maze of little twisting passages, all different.

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