Slashdot Mirror


Ground Crew Back In Touch With LightSail Solar Spacecraft

Yesterday, we noted that the Planetary Society's solar-sail powered craft had lost radio contact with its controllers here on Earth; Engadget reports that the group has issued an update, and the news is good. From the Society's release: "The solar sailing spacecraft test mission, a precursor to a 2016 mission, has now resumed contact after a suspected software glitch affected communications. The LightSail team will soon determine when to attempt deployment of the spacecraft’s Mylar solar sails."

36 of 56 comments (clear)

  1. just a though by Pharago · · Score: 2

    would be nice if everything works, when all the tests are done, to put the sail in a continuos orbit around the sun and get as much speed as possible and then send it to alpha centauri and let it take some pictures from there

    1. Re:just a though by CrystalShepard · · Score: 4, Funny

      It would be nice. That way our descendents four or five generations from now can think "how cute!" as they pass it in the RamJets.

    2. Re:just a though by KGIII · · Score: 1

      I am not sure if RAM jets (or SCAM jets) would work so very well in space unless they carried their own oxygen and, even still, I am not immediately seeing how this would provide propulsion for any length of time.

      --
      "So long and thanks for all the fish."
    3. Re:just a though by meerling · · Score: 3, Informative

      Wrong Ramjet
      Try checking out http://en.wikipedia.org/wiki/Bussard_ramjet

    4. Re:just a though by Tablizer · · Score: 1

      Or EM drives

    5. Re:just a though by Pharago · · Score: 1

      the thing is that if you leave the solar sail orbiting the sun for enough time, it might be theoretically possible for it to achieve near light speed velocity, I haven't done any calculations and so it's almost whishful thinking, but at 10% c it would arrive in just 40 years

    6. Re:just a though by garyisabusyguy · · Score: 1

      Probably not a conventional ramjet
      "In a ramjet, the high pressure is produced by "ramming" external air into the combustor using the forward speed of the vehicle"
      https://www.grc.nasa.gov/WWW/k...

      Perhaps you mean the Bussard ramjet or ramscoop
      "The Bussard ramjet is a theoretical method of spacecraft propulsion proposed in 1960 by the physicist Robert W. Bussard, popularized by Poul Anderson's novel Tau Zero, Larry Niven in his Known Space series of books, Vernor Vinge in his Zones of Thought series, and referred to by Carl Sagan in the television series and book Cosmos. Bussard ramscoops are also seen in Star Trek, where they are situated at the glowing tips of the warp nacelles of spacecraft, although the hydrogen is not used as nuclear fuel."
      http://en.wikipedia.org/wiki/B...

      I like the idea since it would consume the hydrogen that could potentially pierce the spacecraft at relativistic speeds

      --
      Wherever You Go, There You Are
    7. Re: just a though by sanmadjack1624 · · Score: 1

      Dude, chill. Google bussard ramjet, it's not what you think it is.

    8. Re:just a though by KGIII · · Score: 1

      Ah, some theoretical thing with a name similar to an already real jet. I thought I must be missing something because it made no sense to me. Thanks for the link!

      --
      "So long and thanks for all the fish."
    9. Re:just a though by thesupraman · · Score: 3, Informative

      1 - as others have pointed out, you are barking up the wrong tree - these are bussard ramjets, not the type you are thinking of.
      http://en.wikipedia.org/wiki/Bussard_ramjet

      2 - normal ramjets are alive and well and very functional thank you very much - not even new tech.
      Several countries have been using RAMJETS for some time: http://en.wikipedia.org/wiki/BrahMos

      3 - what I suspect you are thinking about SCRAMjets (supersonic combustion..), while rare, are also functional now and have passed
      the point of being considered a scam as they once were, for example you can watch one here: https://www.youtube.com/watch?v=6K_rzuSuqIg
      The Russians and Indians seem quite happy with their SCRAMJETS : http://en.wikipedia.org/wiki/BrahMos-II

    10. Re:just a though by meerling · · Score: 1

      "Jet" can be, and has been, applied to a lot of technologies, but there's no way that NASA could even try to develop it on their budget. So far we haven't even gotten a manned mission to Mars, so one to Alpha Centauri, or any other star system, is pretty much a moot point.
      For now it's just science fiction until somebody will lay apply the necessary resources.

    11. Re:just a though by Brett+Buck · · Score: 1

      It has long been proven that the drag of accumulating the hydrogen greatly exceeds the possible thrust. It's more like a parachute than it is an engine.

         

    12. Re:just a though by Lumpy · · Score: 1, Insightful

      The fault of that lies in Congress.

      Spend Middle East War money on NASA and science and it goes a lot faster.

      --
      Do not look at laser with remaining good eye.
    13. Re:just a though by Lumpy · · Score: 1

      Proven? when did they run that experiment? You have to get up to about 0.05% C to even get them to start working and nobody has launched a test craft.

      --
      Do not look at laser with remaining good eye.
    14. Re:just a though by Immerman · · Score: 1

      No, I'm pretty sure it's the other way around - there's now a real jet which adopted the name of a theoretical fusion engine that had been designed decades before.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    15. Re:just a though by KGIII · · Score: 1
      --
      "So long and thanks for all the fish."
    16. Re:just a though by Immerman · · Score: 1

      No, it's been shown that one particular hypothetical design based on one particular set of assumptions would not be viable. Not that the fundamental concept is flawed. There's a post a few pages up that gives more details.

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    17. Re:just a though by KGIII · · Score: 1

      Decades before 1913? I am not entirely sure that I believe you and I am to search. So, yeah, I think you might be making stuff up.

      --
      "So long and thanks for all the fish."
    18. Re:just a though by Immerman · · Score: 1

      Hmm, my mistake - the ramjet does appear to predate Doctor Bussard considerably - clearly my avionics history is lacking.

      On the other hand, Arthur C. Clarke credits "L'Autre Monde: ou les États et Empires de la Lune" (1657) as both being the first example of rocket-powered space flight and for inventing the ramjet. Though I would imagine they probably discussed something similar to a conventional ramjet, fusion having not yet been imagined. (http://en.wikipedia.org/wiki/Ramjet#Cyrano_de_Bergerac)

      --
      --- Most topics have many sides worth arguing, allow me to take one opposite you.
    19. Re:just a though by KGIII · · Score: 1

      Now that is interesting. The ramjet I was thinking about and linked to would probably get someone into space if one had enough fuel. They are not very complex and work best at high speeds. The V1 had a lot in common with a ramjet as well IIRC. They scale well is my understanding but I do not know how well they would do in space with the added weight penalty from having to carry their own oxygen.

      --
      "So long and thanks for all the fish."
    20. Re:just a though by KGIII · · Score: 1

      Also, I just read my earlier post... Wow... I blame weed.

      --
      "So long and thanks for all the fish."
    21. Re:just a though by jkabbe · · Score: 1

      You'd never get to see the pictures in any case (nor would any human anytime soon).

  2. SourceForge.net is spreading adware installers by Anonymous Coward · · Score: 5, Informative

    SourceForge, the code repository site owned by Slashdot Media, has apparently seized control of the account hosting GIMP for Windows on the service, according to e-mails and discussions amongst members of the GIMP community—locking out GIMP's lead Windows developer. And now anyone downloading the Windows version of the open source image editing tool from SourceForge gets the software wrapped in an installer replete with advertisements.

    Link to original source
    The GIMP developers aren't happy at all about this. They say that Sourceforge impersonated the GIMP developers, and abused the trademarks owned by the GNOME foundation.

    1. Re:SourceForge.net is spreading adware installers by aardvarkjoe · · Score: 4, Insightful

      It's funny, the Slashdot editors used to be aware of the Streisand effect. Apparently they still haven't learned not to try to hide something that's already been publicized widely on the internet.

      --

      How can we continue to believe in a just universe and freedom to eat crackers if we have no ale?
    2. Re:SourceForge.net is spreading adware installers by nadaou · · Score: 5, Insightful

      From a technical standpoint (and that's why we're here isn't it?) the Streisand Effect is actively trying to supress a nibble of information that wants desperately to be free. Which isn't really the case here. Here we have the editors silently ignoring an up-rated story on the firehose in the hope that if it goes away they won't get shit from their corporate overlords. They aren't filing public documents to make it so. Presumably they already have got the shit come down from on high and they don't feel that they're completely irreplaceable.

      You want to stir the shit? Get the quashing story on Soylent News or wherever people with a beef hang out.

      As for me, just another journalistic straw broken in my respect for the good 'ol site.

      --
      ~.~
      I'm a peripheral visionary.
    3. Re:SourceForge.net is spreading adware installers by Anonymous Coward · · Score: 1

      "Most of the Apache Foundation's projects—including Allura, Derby, Directory Studio, the Apache HTTP server, Hadoop, OpenOffice, Solr, and Subversion;"

      This is absolutely fucking disgusting. Have all the fucking ads you want on your site, but DO NOT FUCKING TOUCH THE DEV ACCOUNTS AND MODIFY BINARIES

      This is evil incarnate. I hope someone takes the initiative and sues the living shit for damage to reputation.

    4. Re:SourceForge.net is spreading adware installers by rewindustry · · Score: 1

      please make it so, the roots of this disease go deep, and the creeps responsible must be purged.

    5. Re:SourceForge.net is spreading adware installers by ultranova · · Score: 1

      This is evil incarnate.

      So... Hitler was reborn as Slashdot? That explains why this place is so obsessed with karma.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    6. Re:SourceForge.net is spreading adware installers by toddestan · · Score: 1

      Actually, the Streisand Effect is where something becomes known to people specifically because of the efforts to suppress it. Or in other words, the efforts to suppress something bring attention to something that likely would have otherwise been overlooked and ignored.

  3. Even better by tomhath · · Score: 1

    Land it on Mars and use the mylar sail to cover a cave entrance. A great habitat would be waiting for the colonists. Sure, there are a couple of techincal challanges with either idea - but that can be worked out in the software.

  4. Re:Fix the csv issue? by Megane · · Score: 1

    Why do they need to, now that they've found a finger long enough to push the button again?

    --
    #naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
  5. Re: cach lam bai thi mon van thpt quoc gia by Applehu+Akbar · · Score: 1

    Badum TISH!

  6. How about? by rewindustry · · Score: 1

    SourceFarce MUST allow reporting and discussion of it's actions here on SlashOwned, or we WILL know the reason why?

  7. Beware the 'Pizza Delivery Syndrome' by TheRealHocusLocus · · Score: 1

    The fault of that lies in Congress.
    Spend Middle East War money on NASA and science and it goes a lot faster.

    You cannot successfully argue against war itself as a waste of human resources or a needless monetary expense. Sure you can philosophize and get a show of nodding heads in peacetime, but then something awful happens and someone shouts "Remember the Maine!" or "Hitler will invade the UK, then Mexico!" or "Let's get Bin Laden!" and all is moot. Inquiring line items is useful... such as whether ~$60 billion disappeared while out-sourcing the supply line or whether airlifting $40 billion in 'unmarked bills' into Iraq was a great idea.

    Be sure to tune in C-SPAN today [Sunday] at 4:00pm ET to see how many senators believe the Patriot Act is a good thing. But I'd bet my bottom dollar that all the NSA rhetoric will center on so-called 'call metadata sharing agreements' with nary a word about full content backbone taps which are the greatest threat.

    Government spending is a mysterious process. When it is time for the Fed to mint virtual money for Quantitative Easing, bail out banks by easing their losses, or the Federales to finance wars by raising the trade deficit ceiling and selling bonds to the Chinese we are awash in Magical Unicorn Money. When it is budget time every cent is haggled or omnibussed. Clearly this beast has two heads.

    But you have to get more specific than 'military spending'. Pick something, anything and try to start a grass roots movement to attack it. Or better yet, just spend your time 'selling' space exploration in all of its forms. Neil deGrasse Tyson wasn't completely joking when he suggests that a militarized space race with China (or rumors thereof) would jump-start the process. A new Cold War would certainly unlock that Magical Unicorn Money. It may seem odd but weaponizing space is actually a good idea.

    But there is something I call the 'Pizza Delivery Syndrome', where someone desirous of something, say a Space Program, will seize upon a money-factoid such as this

    cite "Consumers spend around 33 billion U.S. dollars in quick service pizza restaurants each year in the United States. Takeout pizza constitutes the largest share of spending within this category at nearly 15 billion U.S. dollars annually, followed by pizza delivery at around ten billion. This is perhaps unsurprising considering more than 20 percent of U.S. consumers eat takeout or delivered meals at least once a week. While older generations appear less dependent on such services, around 40 percent of 18 to 54 year olds felt that takeout food was essential to their way of life as of November 2014..."

    and create, out of thin air, some hypothetical world where every one who desires a pizza is visited by a Fairy Godmother who smiles and asks, do you really want that pizza or could we all fulfill mankind's most glorious dream? Your wish is my command. In this scenario they always choose the pizza, statistics show. It serves as foundation for acerbic commentary on the wretched excess of modern humans. This is a dead end because (on the whole) people would rather talk about pizza than space.

    Ask not what pizza lovers can do for you.
    Ask what you can do to send pizza into

    --
    <blink>down the rabbit hole</blink>
  8. Re:Fix the csv issue? by sconeu · · Score: 1

    Probably upload a patch that purges or swaps the CSV file as it approaches 32MB.

    Or else use thefinglonger...

    --
    General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  9. Re:Fix the csv issue? by Tablizer · · Score: 1

    A 640,000,000 mile long reset finger oughtta be long enough for anyone.