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Submission + - Yesterday's Broad Power Outage Likely Caused By Geomagnetic Storm (stockboardasset.com)

schwit1 writes: Yesterday, a massive US power grid failure was seen across the entire United States in one simultaneous fashion. San Fransisco, New York, and Los Angeles were the three main areas that were hit the hardest. Each of the areas experienced challenges or shut downs in business commerce. Also, basic infrastructure such as communication networks, mass transportation, and supply chains experienced challenges. To many this seemed apocalyptic with anaylst citing possible cyber attacks amid mounting geopolitical turmoil across the globe. We're shocked that mainstream media didn't revive the failing Russian narrative for another round of fake news to confuse the masses. Personally, I don't think it was a cyber attack or the Russians, but more of a Space Weather Event.

Space weather refers to the environmental conditions in Earth's magnetosphere, ionosphere and thermosphere due to the Sun and the solar wind that can influence the functioning and reliability of spaceborne and ground-based systems and services or endanger property or human health.

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.

Comment Re:Start by banning one time keys (Score 0, Troll) 122

That would be the second thing I would do at every public university, right after banning all federal funding or federally-guaranteed financial aid at any university found to be punishing or persecuting students for exercising their rights of free speech, association, or for their political viewpoints. Too many administrators and Marxist professors at universities today think they have the right to tell students what books they can read and what ideas they're permitted to have or to voice. That doesn't create a learning environment. It creates an indoctrination camp.

Comment Re:Elephant in the room (Score 1) 224

The ability to replace a module with an identical module is not actually modularity. What If I don't want to touch dbus with a 10 foot pole? How about if I want SysV in charge but call systemd for a set of subsystems? SysV is modular enough to deal with that, is systemd?

The scripts aren't generally anything like complex in SysV. They're mostly all the same, and so quite easy to quickly understand.

Systemd doesn't understand imperitives. Sometimes I want the system to just shut up and run the command I say. I don't want to be second guessed.

Systemd is easy to use so long as you happen to want exactly what it wants to do. If you want anything else, it is somewhere between much harder than SysV and impossible.

Have you ever tried to get systemd to mount a btrfs root filesystem in degraded mode? Good luck with that!

Submission + - Inside the Glowing-Plant Startup That Just Gave up Its Quest (backchannel.com)

mirandakatz writes: Back in 2013, the internet was abuzz over a startup that promised Kickstarter backers that it would create a plant that could grow brightly enough to one day replace street lights. The Kickstarter raised half a million dollars, and the controversy was great enough that Kickstarter wound up banning all future synthetic biology projects. But Taxa Biotechnologies was never able to create that much-hyped glowing plant—and last night, they announced that they're officially giving up on the dream. At Backchannel, Signe Brewster has a deep dive into what went wrong, and why biohacking is still such a fraught, complex realm.

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