Source: http://www.wired.com/science/space/news/2007/10/ion_propulsion#
The key: Ion propulsion only needs a tenth of the fuel of a chemical rocket system to reach the same destination, and that means a smaller rocket — and a lot less fuel — is needed to launch missions, such as the Dawn probe. The miserly use of propellant will allow the Dawn probe to become the first to orbit two separate objects — in this case, the asteroid Vesta in 2011 and the dwarf planet Ceres, where it’s expected to arrive in 2015.
Ion propulsion uses positively charged atoms, or ions, to propel a spacecraft. An electron gun is used to knock electrons from a reservoir of xenon atoms, turning them into ions. Then, two charged plates accelerate the ions and eject them from the back of the rocket engine at speeds of 35 kilometers per second, or about 77,000 mph. To avoid accumulating a negative charge, the probe shoots electrons back into the stream of xenon ions leaving the engine.
Pushing a probe farther into space on a light stream of atoms is a trade-off. While it is 10 times more efficient than chemical propulsion, and thus only requires a tenth of the fuel needed by a chemical thruster, it also lacks power. Marc Rayman, chief engineer on the Dawn mission, has dubbed ion propulsion “acceleration with patience.”
DailyTech – IBM Creates Tunable Nanolaser
IBM continues its march towards creating an optical computer with another breakthrough.
GoTopless
Click the source to visit their website
Japan Net Cafe
Short article by DannyChoo about net cafes in Japan
I’ve been to a few myself but there was no bed:
BBC NEWS | Asia-Pacific | Stem cells ‘created from teeth’
Japanese scientists say they have created human stem cells from tissue taken from the discarded wisdom teeth of a 10-year-old girl.
DailyTech – China Blocks iTunes After Olympic Athletes Download Tibet-themed Album
.. LOL
On Monday China’s many internet users began to notice that they were unable to download songs from the popular Apple service iTunes.
Then someone noticed that was the day after Art of Peace Foundation announced the release of “Songs for Tibet,” with music by Sting, Alanis Morissette, Garbage and others along with a 15-minute talk by the Dalai Lama, the exiled Tibetan leader. Now Michael Wohl, executive director of the New York City-based group, claims he has inside information on why iTunes has mysteriously malfunctioned on Chinese networks.
Mr. Wohl states in a phone interview, “We issued a release saying that over 40 (Olympic) athletes downloaded the album in an act of solidarity, and that’s what triggered it. Then everything got blocked.”
DailyTech – Physicists Theorize New Method for Faster than Light Travel
he physicists — Gerald Cleaver and Richard Obousy — have theorized a new idea for faster than light travel that involves manipulating dark energy to propel a spacecraft. According to Space.com the universe — in theory — moved faster than light for a short time after the Big Bang, propelled by dark energy which represents about 74% of the mass energy budget in the universe. Space.com goes on to say that, 22% of the mass energy budget consists of dark matter and what remains of the mass-energy budget in the universe being made up of stars, planets and other things we see.
Some current evidence supports the theory that the fabric of space-time can expand faster than the speed of light. This is said to be because the reality which light travels is expanding itself.
DailyTech – Cassini Spacecraft Investigates Saturn’s Enceladus
“Icy Jets” Suggest Liquid Water May Be Beneath Surface
New pictures taken by the Cassini Spacecraft of Saturn’s moon Enceladus have revealed stunning new features of the moon’s surface. The images display the so-called “tiger stripes” that span the south pole, and reveal the features to be V-shaped cracks a thousand feet deep. Seen for the first time are the sources of active jets inside the features, which are hurling plumes of ice particles high into space.
DailyTech – New Ribosomal Research Offers Fresh Evidence, Understanding of Evolution
Skepticism aside, evolution is steadily being verified and analyzed thanks to cutting edge computing
Nvidia demos real-time GPU ray tracing at 1,920 x 1,080 | News | Custom PC
Nvidia claims that it’s just demonstrated ‘the world’s first fully interactive GPU-based ray tracer’ at the show, which was achieved using a Quadro Plex 2100 D4 Visual Computing System (VCS) containing four Quadro GPUs, each with 1GB of memory.
Nvidia says that ‘the ray tracer shows linear scaling rendering of a highly complex, two-million polygon, anti-aliased automotive styling application.’ Impressively, Nvidia claims that the polished car demo runs at 30fps at 1,920 x 1,080, and includes ‘an image-based lighting paint shader, ray traced shadows, and reflections and refractions’ at three bounces.
Nvidia also demonstrated the demo running at 2,560 x 1,600, although frame rates have not been revealed at this resolution. Even so, the demo makes for a visual treat at this resolution, which demonstrates the gorgeous reflective potential of ray traced games
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