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Submission + - Light Sail propulsion could reach Sirius sooner than Alpha Centauri (arxiv.org)

RockDoctor writes: A recent proposition to launch probes to other star systems driven by lasers which remain in the Solar system has garnered considerable attention. But recently published work suggests that there are unexpected complexities to the system.

One would think that the closest star systems would be the easiest to reach. But unless you are content with a fly-by examination of the star system, with much reduced science returns, you will need to decelerate the probe at the far end, without any infrastructure to assist with the braking.

By combining both light-pressure braking and gravitational slingshots, a team of German, French and Chilean astronomers discover that the brightness of the destination star can significantly increase deceleration, and thus travel time (because higher flight velocities can be used. Sling-shotting around a companion star to lengthen deceleration times can help shed flight velocity to allow capture into a stable orbit.

The 4.37 light year distant binary stars Alpha Centauri A and B could be reached in 75 years from Earth. Covering the 0.24 light year distance to Proxima Centauri depends on arriving at the correct relative orientations of Alpha Centauri A and B in their mutual 80 year orbit for the sling shot to work. Without a companion star, Proxima Centauri can only absorb a final leg velocity of about 1280km/s, so that leg of the trip would take an additional 46 years.

Using the same performance characteristics for the light sail the corresponding duration for an approach to the Sirius system, almost twice as far away (8.58ly), is a mere 68.9 years, making it (and it's white dwarf companion) possibly a more attractive target.

Of course, none of this addresses the question of how to get any data from there to here. Or, indeed, how to manage a project that will last longer than a working lifetime. There are also issues of aiming — the motion of the Alpha Centauri system isn't well-enough known at the moment to achieve the precise manoeuvring needed without course corrections (and so, data transmission from there to here) en route.

Submission + - US Prepares Charges To Seek Arrest of WikiLeaks' Julian Assange (cnn.com)

An anonymous reader writes: U.S. authorities have prepared charges to seek the arrest of WikiLeaks founder Julian Assange, U.S. officials familiar with the matter tell CNN. The Justice Department investigation of Assange and WikiLeaks dates to at least 2010, when the site first gained wide attention for posting thousands of files stolen by the former U.S. Army intelligence analyst now known as Chelsea Manning. Prosecutors have struggled with whether the First Amendment precluded the prosecution of Assange, but now believe they have found a way to move forward. During President Barack Obama's administration, Attorney General Eric Holder and officials at the Justice Department determined it would be difficult to bring charges against Assange because WikiLeaks wasn't alone in publishing documents stolen by Manning. Several newspapers, including The New York Times, did as well. The investigation continued, but any possible charges were put on hold, according to U.S. officials involved in the process then.
The U.S. view of WikiLeaks and Assange began to change after investigators found what they believe was proof that WikiLeaks played an active role in helping Edward Snowden, a former NSA analyst, disclose a massive cache of classified documents.

Submission + - CRTC Ruling: carriers can't use zero-rating (www.cbc.ca)

thisisnotmyrealname writes: CBC Reports:
Internet service providers in Canada should not be able to exempt certain types of content, such as streaming music or video, from counting toward a person's data cap, according to a new ruling by the country's telecommunications regulator.

The move is a win for proponents of a principle known as net neutrality, under which carriers treat all content equally and do not privilege content that benefits them.

"Rather than offering its subscribers selected content at different data usage prices, Internet service providers should be offering more data at lower prices," said Jean-Pierre Blais, chairman of the CRTC in a statement. "That way, subscribers can choose for themselves what content they want to consume."

The Courts

Submission + - UK copyright blackmailer Andrew Crossley loses lic (bbc.co.uk)

saddlark writes: BBC News writes: "Andrew Crossley, the controversial solicitor who sent thousands of letters to alleged illegal file-sharers, has been suspended from the profession for two years."

Andrews Crossley and his law firm ACS: Law have had problems with the UK Courts before. In January, the firm claimed to halt sending copyright infringement letters to alleged file-sharers.

Comment No. (Score 0) 213

No, we need unindexed social networking, so my pictures and data aren't one google search away from being discovered by an employer or curious passerby. Social networking is, nearly by definition, for the purpose of communicating clearly with people one is formally acquainted with. There are other forums for anonymous communication.
Wireless Networking

Submission + - What's killing your Wi-Fi? (pcpro.co.uk)

Barence writes: "PC Pro has taken an in-depth look at Wi-Fi and the factors that can cause connections to crumble. It dispels some common myths about Wi-Fi problems — such as that neighbouring Wi-Fi hotspots are the most common cause of problems, instead of other RF interference from devices such as analogue video senders, microwave ovens and even fish tanks. The feature also highlights free and paid-for tools that can diagnose Wi-Fi issues, such as inSSIDer and Heatmapper, the latter of which maps provides a heatmap of Wi-Fi hotspots in your home or office."
Printer

Submission + - Researchers invent inkjet that prints out skin (geek.com)

shougyin writes: If you’ve ever seen the lesser-known Sam Raimi movie Darkman, you probably remember that the plot involved the main character, Dr. Westlake, trying to figure out a way to “print” liquid skin to help burn victims. Westlake never did figure out how to keep the synthetic skin from destabilizing past the 98 minute mark, but luckily, Wake Forest Instititute for Regenerative Medicine researchers seem to have mastered it, showing off their amazing skin printer that uses living cells instead of ink.

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