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X-Prize Lunar Lander Competition a Go

Tiger4 writes "The X-Prize foundation and NASA have signed off on a $2.5 million prize for proof of concept lunar lander vehicles. From the article, 'NASA Deputy Administrator Shana Dale told MSNBC.com that the point of the competition was to "take advantage of new innovative technologies that have been developed" since the last lunar landing, during the Apollo 17 mission in 1972." There are two levels of competition, "In the Level 1 competition, the vehicles must be in the air for at least 90 seconds during each leg of the round trip, and land on a flat, even surface. The Level 2 competition is harder -- requiring 180 seconds of flight each way, with a rocky, lunar-style landing site.' NASA and X-Prize people are still working on the final rules, but they are already signing up teams and expect to see vehicles in time for the X-Prize exhibition in New Mexico, October 18-21, 2006."

124 comments

  1. Consolation Prize by foundme · · Score: 2, Interesting

    Is there a reason to have consolation prizes for second and third place? I wouldn't mind "cost-recovery" of up to $xxx for non-winners, but to actually award them a prize? There is no room for "good enough" in Space.

    --
    Please stop entering code 2,2,7,6,6,4
    1. Re:Consolation Prize by yincrash · · Score: 3, Insightful

      what if three different finalists all are successful, just some are better than others? just because there is one winner doesn't mean the runners up are failures.

    2. Re:Consolation Prize by Shivetya · · Score: 1

      because the winner may not pan out in full scale development whereas second place or beyond might. Also by the time the actual design and build of the final systems are in place there might be changes in tech which advance the other finishers to the top

      --
      * Winners compare their achievements to their goals, losers compare theirs to that of others.
    3. Re:Consolation Prize by Anonymous Coward · · Score: 0

      There is no room for "good enough" in Space.

      Actually as the Space Shuttle and (in other ways) the whole Russian space program have shown this is not the case.

    4. Re:Consolation Prize by Neurotoxic666 · · Score: 2, Insightful
      There is no room for "good enough" in Space.

      Nobody will end up in 2nd or 3rd place with a "good enough" idea either. It is going to be some pretting friggin good ideas, worthy of a prize. Even if some idea does not win the contest, it might very well inspire some genius elsewhere to come up with something better or it could also be improved, tested and used. You never know.

      --
      You are more than the sum of what you consume. Desire is not an occupation.
    5. Re:Consolation Prize by Anonymous Coward · · Score: 0

      There is no room for "good enough" in Space.

      Sure there is. The Apollo spacecrafts were "good enough". The Mars Rovers were "good enough". Some Apollos failed and I am certain the Spirit team wishes the wheel bearing seals were perfect. The biggest problem that the American space program faces is that "good enough" isn't considered good enough. Instead, NASA is looking for "perfect" and ending up with the shuttle program.

    6. Re:Consolation Prize by floamy · · Score: 1

      Do you understand the point to the X-Prize at all?

    7. Re:Consolation Prize by The+MAZZTer · · Score: 1

      This year's second place could improve their idea enough to become next year's first place.

    8. Re:Consolation Prize by fishbowl · · Score: 3, Interesting

      >Do you understand the point to the X-Prize at all?

      I don't. It occurs to me that anyone capable of claiming such a prize should be doing it *anyway.*

      It would be more impressive if somebody did it without regard for the prize. Didn't even claim the prize, didn't even enter the contest, just fulfilled the requirements ahead of any of the contestants.

      That would be hilarious.

      --
      -fb Everything not expressly forbidden is now mandatory.
    9. Re:Consolation Prize by kd5ujz · · Score: 1

      Remember, your GOV issued equipment is made by the lowest bidder. If 3 companies complete the task, and the second place winner offers a lower bid than the first and third, the second is going to get the contract. First place may have put on a better show, but its all about budget cuts. This logic is why we still use the M16A2.

      --
      -William
      God is everything science has yet to explain.
    10. Re:Consolation Prize by Anonymous Coward · · Score: 0

      Lowest bidder prepared to go through the government paperwork :)
      There's low and then there's government contractor low.

    11. Re:Consolation Prize by Anonymous Coward · · Score: 0

      If you're not clearly the winner, then you're just not the kind of winner we need. As such, we probably shouldn't be giving out a prize, or wasting our time noticing at all. If you do something neat, then we'll make a footnote out of it, or if you leave a greater impact in the long run I guess we'll have to recognize you in another way, but in a put-up or shut-up situation like gettin' on the moon, you either win, or you get the "participant" ribbon, and an invitation to watch someone else (rightfully) accept the prize you only kinda earned.

    12. Re:Consolation Prize by Jafafa+Hots · · Score: 2, Interesting
      Are you kidding? Space is OFTEN about "good enough." Weight is at a premium.

      In the lunar lander for Apollo, you could puncture a hole clear through the hull by dropping your screwdriver. In some places it was as thin as several stacked sheets of aluminum foil. It held in the oxygen so it was "good enough."

      Looking at the shuttle, there are many places where they settled on "good enough." In fact, you could say the entire design was a "good enough" compromise from the SSTO concepts they had started out with. And frankly, in a lot of ways, the shuttle turned out not to have been good enough at all.

      --
      This space available.
    13. Re:Consolation Prize by metalcup · · Score: 1

      why has the parent been modded troll ? Why is it trolling, especially when IMO he has a valid point, or atleast a point that can be discussed about?

      --
      "Laziness is an optimisation protocol"
    14. Re:Consolation Prize by Ihlosi · · Score: 1
      There is no room for "good enough" in Space.

      Ha ha. Judging from this comment, you don't really know a lot about the technical and economic aspects of space flight. Usually, it has to be inexpensive and "good enoug", because even inexpensive space flight costs a helluva lot. Try going for expensive and the best money can buy, and you'll be broke before even getting anything on the launch pad.

    15. Re:Consolation Prize by khallow · · Score: 1
      What a bizarre concept of failure and success.

      First, failure is usually necessary to success. It is rare that someone succeeds on the first try. The experience gained from previous failures can also make the difference between success and failure.

      Second, the concept, that only the winner of a contest has anything to contribute, is bizarre. It doesn't work that way in real life. We're not in your "rat-race". We're not playing by your rules. The second group on Mars would probably contribute as much innovation as the first group.

  2. Cost control measures... by Silas+Palmer-Cannon · · Score: 3, Insightful

    This is probably a good way to gain technology while minimizing cost. How much would it cost for NASA to do this in house? 100 million? 200 million? Too expensive? Here's the solution. Offer college students 2.5 million as a prize for a "competition". Good work guys.

    1. Re:Cost control measures... by l2718 · · Score: 2, Insightful

      Note that NASA would be spending the $100M to ensure that things will work, preiod. The private developers are willing to assume a greater level of risk -- which is the main reason for the cost saving.

    2. Re:Cost control measures... by DerekLyons · · Score: 2, Interesting
      This is probably a good way to gain technology while minimizing cost. How much would it cost for NASA to do this in house? 100 million? 200 million? Too expensive? Here's the solution. Offer college students 2.5 million as a prize for a "competition". Good work guys.
      Historically such competitions and prizes tend to breed solutions optimized towards winning the prize or competition - not general technologies.

      Furthermore, I fail to see what 'technologies' NASA stands to gain here. Vehicle control algorithms of this nature are medium well explored and must be tailored to the individual vehicle, so this contest doesn't really much offer there. The fuels, engines, controls, guidance, tankage, and structure of a full scale lander will be radically different from a model lander as well. (Take guidance for example - the real thing will use inertial/radar with visual backup (from the cockpit). The models will almost certainly use GPS with visual backup - from the operators position.)

      The contest makes NASA look modern, using 'open source' and 'competition' and 'the marketplace' and all the other current buzzwords, but it's almost certain to yield little beyond good press.

    3. Re:Cost control measures... by ghjm · · Score: 1

      Given that a lack of good press is the single most critical factor inhibiting NASA's ability to do interesting projects, I'd say that if "all" they get out of this is good press, then it's money well spent.

    4. Re:Cost control measures... by MoonBuggy · · Score: 1

      It's the same way that Scaled Composites spent ~$25million in order to win $10million back with the original X Prize. The prize itself is a nice way to ensure some immediate payback of the development, with a definite figure given as well as a reason for a company to think "hey, we could produce [product], why didn't we ever try building one before?".

      After the first payoff it's then up to the company to make money just like any other business, as Scaled Composites did by signing with Virgin Galactic. It's not a way to replace NASA's R&D, it's just a way to nudge the private sector in the right direction.

    5. Re:Cost control measures... by Yvanhoe · · Score: 1

      I, for sure, wouldn't go to the moon in a college student vehicle. Call me snob...

      --
      The Wise adapts himself to the world. The Fool adapts the world to himself. Therefore, all progress depends on the Fool.
    6. Re:Cost control measures... by JasonKChapman · · Score: 2, Informative
      Historically such competitions and prizes tend to breed solutions optimized towards winning the prize or competition - not general technologies.

      I guess that depends on how you define "historically." There have been some pretty major technological and societal changes brought about by such competitions. One of them is accurate clocks and, thus, accurate trans-oceanic navigation:

      The Board of Longitude was established in England in 1714 and offered 20,000 pounds (12 million dollars in today's currency) to whoever would come up with a method for determining longitude with in a distance of 30- nautical miles during a voyage from England to the West Indies.
      --
      Sorry, I'm a writer. That makes you raw material.
    7. Re:Cost control measures... by Rei · · Score: 1

      Amen. Not only guidance - lets look at the thrust requirements. 180 seconds each way, at 9.8 m/s^2 -> ~1800 sec delta-v. Sounds an awful lot like an actual landing, right? Well, look at the rules: the craft gets to *refuel* at its landing spot. This is a *huge* advantage for the models. Also, the models are tiny. It's akin to saying "Look at my model rocket! Silly NASA and their Saturn Vs!"

      On the other side, the models need way too much thrust for their mass in order to stay aloft on Earth. Lunar landers would use much smaller engines. Also, the engines would need to be optimized for operating in a vaccuum, not on Earth. Then, there's the additional lunar tech challenges -- dealing with a vaccuum, dealing with temperature extremes (which can be very nasty to spacecraft - your hydraulics may freeze, your fuels may freeze or lock up, etc), dust collection during the time you're down, etc.

      In short, these are nothing like real lunar landers. Not to mention, there are loopholes in the rules wide enough to drive a truck through :P You could fly in a bicycle-powered blimp from point A to point B and back as long as you used rockets (of any size, even bottle rockets) to help you on liftoff and descent. If I recall the rules correctly, powered thrust is only specified for during those times.

      --
      Did he just go crazy and fall asleep?
  3. Not me, I'm waiting for the X-Prize to... by dietrollemdefender · · Score: 1, Interesting
    Andromeda. The hundred-trillion-gagillion dollar prize would be worth it then.

    Ok, dumb joke. But, it's like the X Prize Organization is escalating it's spnsorship to new heights. I find this quite encouraging. What a way to push science and engineering. This really tickles my libertarian bone - no government involvement.

    Oops, I forgot! There's some real libertarian haters here on /.. I guess because they confuse Libertarians with conservative Republicans?

    NOTE: Using a lowercase 'l' when describing my Libertarian tendancies was to hint that I haven't quite drank their Kool-Aid (TM).

    1. Re:Not me, I'm waiting for the X-Prize to... by Anonymous Coward · · Score: 0

      And yet you go out of your way to mention Libertarianism...ITS A TRAP! ITS A TRAP! ITS A TRAP!

    2. Re:Not me, I'm waiting for the X-Prize to... by Anonymous Coward · · Score: 0

      Oops, I forgot! There's some real libertarian haters here on /.. I guess because they confuse Libertarians with conservative Republicans?

      No, the problem is that the Libertarian Party has gone and rounded up some major kooks to support them. Try going to some of these candidates' dinner parties (getting in is pretty cheap, they're not Republicans after all). You'll get them to nod their head in agreement when you're talking about minimal governance. Sure, the FDA has to go. Sure, the EPA is just in the way. Sure, business taxes are rough.

      Then you mention how it'll be nice once the government quits protecting the corporations as well as the people. I got one candidate to try and crawl onto his dinnerplate and hide in his lobster when I went on the offensive against the corporate veil. Another actually pissed himself when I mentioned how much better medicine will be when the managers signing off on drugs are tried for murder when it's discovered they manipulated study data to hide side-effects of a pill that was marketed to hundreds of thousands. A third had me thrown out when I brought up the issue of patents.

      So yeah, until the Party cleans up it's act, it's in the same mess as the current Republican Party. Only without the gigantic donations to buy TV time and votes.

    3. Re:Not me, I'm waiting for the X-Prize to... by Zaphod2016 · · Score: 1, Troll

      Life is a trap, and we're all already stuck.

      However, if your libertarian, republican, democratic or communist opinions serve to make the world a better place, I'm all for them.

      America is an amalgamation of greatness.

    4. Re:Not me, I'm waiting for the X-Prize to... by Anonymous Coward · · Score: 0

      Socialist are naive and hate libertarians. Socialism works in the short term and life is better, but in the long term it seriously dampens the human spirit and destroys nations who embrace it.

      The one thing I've noticed about socialists and american "liberals" is that they claim to love freedom and freespeech. Sure they dont care about moral issues, but if you are on the oposition and disagree with them they try to insult and censor you.

      True freedom is economic,social, but also freedom of thought and speech. American "liberalism" and socialism have turned into a perverted form a facism which supress freedom of thought and speech to an extreme while placing many restrictions on the economy, but they do allow social freedom. The American republicans dampen social freedom a considerable amount while hindering freedom of thought and economics about equally.

      I'm a libertarian because I believe in freedom and liberty without censorship.

    5. Re:Not me, I'm waiting for the X-Prize to... by Anonymous Coward · · Score: 0

      * form of facism

      correcting a typo

    6. Re:Not me, I'm waiting for the X-Prize to... by dietrollemdefender · · Score: 1
      However, if your libertarian, republican, democratic or communist opinions serve to make the world a better place, I'm all for them.

      Maybe. That's why I'm hesitating to drink the Kool-Aid.

    7. Re:Not me, I'm waiting for the X-Prize to... by Zaphod2016 · · Score: 1

      Hahaha. I'll drink to that. ;-)

  4. Good use of NASA $$$ by rdoherty · · Score: 1

    Talk about cost-effective NASA spending...

    1. Re:Good use of NASA $$$ by mikesd81 · · Score: 2

      This is good sue of NASA money if any of the projects get implemented or even if some ideas from the projects get implemented.

      It's good that NASA is looking outside their walls for ideas too. Their are lots of brilliant people out there. It's time we tap into that. Space travel is obviously dangerous and tricky business. Anything that makes it safer and and easier, even if it's just one thing, is worth them money. Spend the 2.5 mil and get some ideas for a new ship? Doesn't sound bad.

      --
      That which does not kill me only postpones the inevitable.
  5. "Bounty" based development by Null+Nihils · · Score: 5, Insightful

    I wonder if we'll see an increase in "bounty" based development. It certainly seems likely. A large number of smaller F/OSS projects also offer a significant monetary prize or "bounty" for someone who can implement tech to solve a specified need, want or problem. The Google Summer of Code is also, in my mind, a similar deal.

    This stands in contrast to older, beaurocratic methods that are closed and contract-based.

    This new openness is, in my opinion, closer to the ideals of a free market than the latter mentioned system.

    1. Re:"Bounty" based development by Duncan3 · · Score: 1

      Yes. Lots more.

      Why? Becasue it is CHEAP, very cheap. 10-100x cheaper then paying poeple do it.

      Summer of Code pays a timy amount compared to just getting a job.

      --
      - Adam L. Beberg - The Cosm Project - http://www.mithral.com/
    2. Re:"Bounty" based development by grazzy · · Score: 1

      The value of your job could be 100x. Chances you get a summer internship writing actual code for a project that thousands of people might use is, quite slim.

    3. Re:"Bounty" based development by supabeast! · · Score: 2, Insightful

      "This stands in contrast to older, beaurocratic methods that are closed and contract-based."

      How do you think those contracts are often won? The government has often, and still does, set up contests like this, where big defense contractors compete for a bounty which comes in the form of a contract to produce the final product. In aerospace the bureaucracy is not so much a problem in the contracting system -- even without corruption and bureaucrats there are still only a tiny handful of people and corporations capable of handling any large aerospace project -- as it is in the implementation and maintenance of projects, where the ongoing costs and wasted productivity weigh down the entire system.

      That said, I think that the bounty system is a gimmick that won't last too long. Smart executives seeing the success of bounties in the software world will be spurred to just start hiring F/OSS developers with some of the money F/OSS saves them in the first place, and the bounties will start fading away as their unnecessary - at least they will if Larry and Sergei at Google are setting an example.

    4. Re:"Bounty" based development by subnomine · · Score: 1

      On the topic of "bounty development," Kodak in 1998 offered a prize for coders to develop scripts for their new digital cameras (DC260) so the idea has been around at least that long.
      ---
      I took the competition to mean that Kodak and FlashPoint couldn't figure out anything interesting to do with a CPU in a camera. Or maybe they just didn't know what to do with their scripting language which sucked as badly as a high school science fair project. I wasn't about to spend any time using it...but I must have had the wrong documentation because somehow someone managed to write a motion detection program that took a picture when the image changed by some measure. They won first prize. (All the rest of the submissions where HTML generation scripts which shouldn't be done on the camera, in my opinion).
      ---
      One would think that all cameras would be customizable/programmable these days. In case someone in the camera industry is reading this: I certainly would like a motion detection option. I would also like to program movement detection and focus calculations for myself.

  6. Just how strict are the rules anyway? by Jeremi · · Score: 3, Funny

    Can I win the contest using my parachute-based landing system?

    --


    I don't care if it's 90,000 hectares. That lake was not my doing.
    1. Re:Just how strict are the rules anyway? by gkhan1 · · Score: 1

      I'm pretty sure that you can't use any technologies that are based on there being an atmosphere. That is, no helicopters, no parachutes. Basically, it's supposed to work equally well in a vacuum.

    2. Re:Just how strict are the rules anyway? by Davey+McDave · · Score: 2, Informative

      I doubt so, considering the moon has little to no atmosphere. No air resistance = parachutes next to useless.

      --
      I've got the spirit, lose the feeling.
    3. Re:Just how strict are the rules anyway? by operato · · Score: 0

      i dunno... what if the piece of junk shot particles at the parachute (like a solar sail concept?) would it still work?

    4. Re:Just how strict are the rules anyway? by Solra+Bizna · · Score: 1

      Because then you might as well just shoot particles at the ground and save yourself the parachute.

      -:sigma.SB

      --
      WARN
      THERE IS ANOTHER SYSTEM
    5. Re:Just how strict are the rules anyway? by operato · · Score: 0

      it's harder that way to stabilise space craft.

    6. Re:Just how strict are the rules anyway? by gstoddart · · Score: 2, Funny
      Can I win the contest using my parachute-based landing system?

      Only if you're willing to wear the Wile E Coyote outfit and release the video under creative commons.
      --
      Lost at C:>. Found at C.
    7. Re:Just how strict are the rules anyway? by John+Newman · · Score: 2, Funny
      i dunno... what if the piece of junk shot particles at the parachute (like a solar sail concept?) would it still work?
      It'll work as well as a sailboat with a big fan behind the sails.

      See Newton's Laws.
    8. Re:Just how strict are the rules anyway? by Anonymous Coward · · Score: 0

      The sad thing is that the Earth-based prototype must work at six times the gravity of Moon. This means the engines used must be bigger than the ones that could be used on Moon

    9. Re:Just how strict are the rules anyway? by camperdave · · Score: 1

      Only if you're willing to wear the Wile E Coyote outfit and release the video under creative commons.

      Oh, and don't forget the "Ouch" sign.

      --
      When our name is on the back of your car, we're behind you all the way!
  7. That's great, but... by iced_773 · · Score: 0


    I would like to see a competition calling for teams to send vehicles to the REAL moon, just like the Ansari X-Prize winners had to actually go into space.

    1. Re:That's great, but... by Anonymous Coward · · Score: 0

      If you really can call it that. Hell, they couldn't have even made LEO.

    2. Re:That's great, but... by morgan_greywolf · · Score: 0, Offtopic

      I would like to see a competition calling for teams to send vehicles to the REAL moon, just like the Ansari X-Prize winners had to actually go into space.

      First off, the contest was for a lunar lander not for a vehicle that can go to the moon, another vehicle to orbit the moon, and another vehicle to land on the moon, because that is what it would take.

      Do you have idea what the costs involved are in building a rocket capable of lifting a vehicle away from the earth's orbit so it can travel to the moon? According to this article, one of the biggest reasons the Apollo program was cancelled was the cost: It cost $1.2 billion to launch a Saturn V in 1966, with a total allocation for the saturn program of $6.5 billion.

      Putting that in perspectve and adjusting for inflation in terms of 2005 dollars, the cost today would be about $205 billion.

      Not even Bill Gates has that kind of money.

  8. Already been done by OYAHHH · · Score: 0

    It's called the McDonnell Douglas DC-X.

    You would think NASA could come up with a more wasteful way to waste money...

    --
    Caution: Contents under pressure
  9. Hammer, Feather, Freefall on the Moon: Revisited by Anonymous Coward · · Score: 0, Offtopic

    "Fall heavy towards the moon, and the moon falls also towards you." -- Nietzsche

    Hammer and feather are dropped simultaneously from equal heights (as measured by distance from the center of the moon), separated laterally by a distance substantially less than the moon's diameter. Both hammer and feather experience force from the moon's gravity proportional to their mass, and hence both accelerate at the same rate. Meanwhile, the moon is also accelerating towards the other two objects, but unevenly so: the hammer exerts a greater gravitational pull due to its greater mass. The moon is therefore subject to a torque, causing it to accelerate more rapidly towards the hammer.

    The hammer is first to hit the ground.

    Anyone who denies this truth is a spatially absolutist lunocentric whose refusal to recognize the validity of hammer mechanics/experience places him wholly beyond the help of Galilean metaphysics. Such hammer (feather) rejectionists ought to be banished to the stars, for their own good and for the good of not only hammers and feathers but all subjugated smaller objects, everywhere, who find themselves victims of this scientifically perpetrated emassculation.

    --
    a756f345ec354225c08ff1a10a43162a

  10. Armadillo for the win. by kraemer · · Score: 2, Interesting

    Armadillo Aero has this one nailed. http://www.armadilloaerospace.com/

  11. Two top contenders by chroma · · Score: 3, Informative

    A couple of the top contenders, who have been working on this type of vehicle even before the prize was announced are: Masten Space Systems and John Carmack's Armadillo Aerospace.

    --

    Your design to a real part online: Big Blue Saw
    1. Re:Two top contenders by chroma · · Score: 1
      --

      Your design to a real part online: Big Blue Saw
  12. Obligatory by Life700MB · · Score: 2, Informative


    Obligatory images from the first prototype.


    --
    Superb hosting 20GB Storage, 1_TB_ bandwidth, ssh, $7.95

  13. Reusing old technology... by __aaclcg7560 · · Score: 1

    There's no rule against reusing old technology like the Apollo Guidance Computer? Or building a low-tech Salvage 1 is there? Granted it's not sexy but it should work. :P

  14. Gravity? by BaronSprite · · Score: 2, Insightful

    Wouldn't the thrust systems need to be significantly different for a 180 second hop on earth when compared to the moon? Not to mention weight of fuel and what not...

    1. Re:Gravity? by TemujinKhan · · Score: 2, Informative

      uh.. yeah. better question is to ask what should the safety margin for over engineering a project of this scope should be. Gravity on the Moon is 1/6 that of Earth, so that implies if the system works here, then you have a built in 6x safety margin there. (never mind that the whole point of the competition is to develop a workable auto-pilot assisted takeoff/landing system)

      --
      ----- watch the monkey with the wrench
    2. Re:Gravity? by Anonymous Coward · · Score: 0

      That occurred to me as well: you could argue (not very well) that being able to do it for three min at 1G is similar in difficulty to 18 min at 1/6G. Also, unless they are gifted with a very cool, calm, day, the craft may have to be able to handle interactions that you just don't see on most airless planetoids. That said, any team that could pull this off should have no trouble adapting to an environment where they can react 6 times slower and the terrain won't try to wander away the moment you take your eyes off it.

    3. Re:Gravity? by Eideewt · · Score: 1

      That's what I thought too. Maybe the idea is that moon hops would be much longer.

    4. Re:Gravity? by grozzie2 · · Score: 5, Insightful
      Figure out the impulse required to do a 3 minute hop at the bottom of a 9.81 m/s^2 gravity well. Now figure out the impulse required to go from a stable low orbit to a soft landing in a 1.635 m/s^2 gravity well. The numbers are going to be amazingly close. For the next step, figure out your stability problem for a 3 minute hop, vertical takeoff, lateral displacement, and then soft landing with a 3 minute flight time, including silly things like wind drift and possibly some random turbulence enroute. Refigure the problem for the orbit to lunar surface in vaccuum.

      Overall, not a bad deal. For 2.5 million, you get propulsion and stability that's on par with that needed for a lunar landing. Add some guidance, and you have the whole package. Of course, this doesn't really touch on the actual expensive part of the project, and that's the ride up to lunar orbit.

      Will have to wait till the final rules are published, but, there's a big ticket item missing from the discussion so far, and that's the subject of mass budget. If this is going to really represent a lunar landing package, there will be an all up mass budget for the lander, and, a specific amount of that mass needs to be reserved for payload.

      The problem for the Apollo program wasn't making a lunar lander, it was making a lunar lander that fit within the mass budget, and still had room left for 2 astronauts. That required compromises and risk management that wouldn't be acceptable in today's climate. If folks think a space shuttle is a 'scary contraption', then they should go take a look at the LEM used by the Apollo program. When the candles were lit for an Apollo mission, there was NOBODY trying to kid around that it was a 'safe' endeavour, and EVERYBODY understood, and accepted, the possibility of a mission ending in fatal failure. the LEM was probably the most fragile contraption ever lofted into space.

      The Apollo program had a 81% success rate, with 1 of the 11 attempts resulting in a fatal outcome even before it was launched. 10 of 11 attempted launches actually went off, and one of those failed it's primary mission, but thru hard work and some ingenuity, mixed in with a lot of good luck, the astronauts actually got home alive. Compared that to the shuttles 98% success rate, the Apollo success rate was atrocious. Shuttle has had 2 failures in well over 100 launches, Apollo had 2 failures in 11 attempts, and 10 launches.

      Here on /. folks like to comment 'well if we could go to the moon 50 years ago, why not today'. Frankly, 'we' didn't go to the moon 50 years ago, it was our parents and grandparent generation that did that. They were willing to accept risk as a fact of life, analyze it, deal with it, and accept the results. The society of america today could not possibly put a man back on the moon, the public doesn't have the tolerance for the cost, either financially, or in human costs. They want a system that's guaranteed to work, and guaranteed to not break on the way. Well folks, with rocket technology, it ain't gonna happen. You have to either accept the risk, or, go develop some new breakthru propulsion system that doesn't rely on strapping people on top of a huge bomb, then doing a controlled explosion to send it into orbit.

      If the shuttle system is being scrapped because it's not 'safe enough', then stop looking to the moon and beyond for rockets. Shuttle is just a baby, meant to go to low orbit. The big boys that are needed to go farther can make big bangs substantially larger than a space shuttle is capable of. If you are going to strap the quantities of lox and h2 together in tanks light enough to carry on up to orbit and beyond, once in a while the whole mess is going to go boom. Accept it, deal with it, or forget it. That's what your grandparents did, and thats how they got to the moon, and they did it using slide rules and will power.

    5. Re:Gravity? by khallow · · Score: 1
      If the shuttle system is being scrapped because it's not 'safe enough', then stop looking to the moon and beyond for rockets. Shuttle is just a baby, meant to go to low orbit. The big boys that are needed to go farther can make big bangs substantially larger than a space shuttle is capable of. If you are going to strap the quantities of lox and h2 together in tanks light enough to carry on up to orbit and beyond, once in a while the whole mess is going to go boom. Accept it, deal with it, or forget it. That's what your grandparents did, and thats how they got to the moon, and they did it using slide rules and will power.

      There's plenty of risk-takers in the the world who would accept the risks of launching something in space. They don't control of NASA or the other government space programs.

  15. Re:Hammer, Feather, Freefall on the Moon: Revisite by TheDreadSlashdotterD · · Score: 1

    It was funny the first few times.

    --
    I have nothing to say.
  16. Moonshot awareness 101: Find+highlight all errors! by D4C5CE · · Score: 1
    ...as in:
    the vehicles must be in the air
  17. This is the Government... by Ruff_ilb · · Score: 3, Interesting

    $2.5M is NOTHING to them. Nothing.

    I hate to play this card, but by the end of 2006, we will have spent a (conservative) estimate of $315 billion in Iraq.

    Heck, compare this to non-government entities. If ol' Bill could get college students to write him a completely new OS for 2.5M, he'd probably jump at the chance.

    --
    http://www.TheGamerNation.com/Forums
    1. Re:This is the Government... by Tony+Hoyle · · Score: 4, Funny

      If ol' Bill could get college students to write him a completely new OS for 2.5M, he'd probably jump at the chance.

      Why, since they already did it for free?

  18. Before or after? by not-admin · · Score: 1

    Does the 90 seconds in the air have to be before it blows up^H^H^H^H^H^H^H^H possibly experiences capsule divergence issues?

  19. something isn't quite right about this. by Anonymous Coward · · Score: 2, Interesting

    $350,000.00 for first flight? I don't think so. A decent aerospace engineer must cost a business around 120 grand or so for a year of work, and then there are all the materials, construction, infrastructure.

    This sounds more like a bonus add-on to the existing x-prize than the "new prize" it's being touted as. Or maybe it's another cookie to try and get a guy like Paul Allen to dump far more into it then he'll ever get back...except it is a nice thing for him to do...give back.

    Don't get me wrong...I'm all for moving the pork away the government and back to the citizenry...my quibble is with the portrayal.

    If I'm right, this has a stink to it...media hype. Just be honest about what it is...a little extra cash to the current X-prize competitors to move in a different direction for awhile.

    it would be great to see one or more small, agile aerospace companies emerge from this. The entrenched players (raytheon, lockmart, boeing) are pretty fucking pork laden, massive management overhead, shareholder burdens, lobbying payola. Not bin laden, pork laden.

    1. Re:something isn't quite right about this. by zippthorne · · Score: 1

      Maybe they're planning on people adding to the prize as time goes on, just like the X-prize.

      --
      Can you be Even More Awesome?!
    2. Re:something isn't quite right about this. by carambola5 · · Score: 2, Insightful

      The labor is definitely at issue, but you make one flaw in your argument.

      Aerospace engineers in smaller businesses do not make 120 big ones in a year. That is preposterously high. The cost adds up when you add more engineers to the equation. At a minimum, you need a jack-of-all-trades aerospace engineer (ie: theory, design, drafting, and analysis... a fairly rare combination seeing as drafting is usually "below" an aerospace engineer), an electrical engineer, a software engineer, maybe a propulsion engineer, and a project manager. That's 4-5 salaries at the absolute minimum. Generally, you want at least two of each type of engineer (the second need not be full time on the project) to bounce ideas back and forth. Quality and safety engineers are also nice to have, though they would split time amongst a company's projects.

      Now add your materials, construction, and infrastructure: custom one-off fabrication is NOT CHEAP, especially with the typical requirements put forth by NASA (generally NASA's GIDEP requirements involve extremely high quality, and expensive, commercial off-the-shelf compoents)... though it will probably only add up to $100k, depending. Construction is more labor... a few techs working on it, albeit at lower salaries than the engineers. And in an ideal world, infrastructure doesn't matter much if you have enough projects amongst which to split the costs.

      No, aerospace engineering is not an inexpensive enterprise. But removing NASA's interaction (and obscenely high "support staff" for your project) is a wonderful step.

      I think the first line of my sig should explain where I'm coming from.

      --
      IWARS.
      People, in general, disappoint me. Politicians even more so.
    3. Re:something isn't quite right about this. by Iron+Condor · · Score: 2, Informative
      A decent aerospace engineer must cost a business around 120 grand or so for a year of work,

      It's a little dangerous to post concrete numbers in a field that you don't actually know anything about. I consider myself "a decent aerospace egineer" and I cost my employer something like 1/4 million per yer. And I have single-digit years of seniority - there's much more expensive folks out there. There's also cheaper people, of course. But when you include things like benefits, $120k p.a. is barely going to buy you an entry level technician.

      ...to try and get a guy like Paul Allen to dump far more into it then he'll ever get back.

      You're making the mistake of underestimating a good businessman. With all the paid lectures and tours and broadcasting rights, Paul Allen definitely made his money back. The couple million X-prize were just the icing -- on the day of the flight and the days right after, a couple seconds of footage commanded six figures. Exact numbers are hard to come by, but it is an open secret in the aerospace community that Allen definitely didn't lose any money in the operation...

      --
      We're all born with nothing.
      If you die in debt, you're ahead.
    4. Re:something isn't quite right about this. by carambola5 · · Score: 1
      I cost my employer something like 1/4 million per yer.

      Cripes, I work for the wrong aerospace company.

      Um... well done!
      --
      IWARS.
      People, in general, disappoint me. Politicians even more so.
    5. Re:something isn't quite right about this. by john.r.strohm · · Score: 1

      You have to figure in overhead cost.

      The engineer's salary is just the beginning. You also have to figure in taxes, Social Security, cost of benefits, how much it costs to pay for the engineer's desk, light, heating and air conditioning, computer, and all the other things.

      Most places, overhead cost for an engineer runs around 100% of his/her salary, meaning that an engineer whose gross salary (before taxes and other deductions) is $60K/year actually costs the employer ca. $120K/year.

  20. Re:Hammer, Feather, Freefall on the Moon: Revisite by porkmusket · · Score: 1

    No it wasn't.

  21. Moon Tether by aznoohwee · · Score: 1

    How hard would it be to deploy a tether on the moon and be able to pick up and move a lander? The gravity on the moon is obviously less, so the strength requirements of the rope would be significantly less. I wonder if its possible to use a hemp rope suspended from a satellite to move things on the moon.

    1. Re:Moon Tether by anagama · · Score: 2, Funny

      You better lay off smoking that rope for a spell.

      --
      What changed under Obama? Nothing Good
    2. Re:Moon Tether by Anonymous Coward · · Score: 3, Informative

      If you mean like a synchronous skyhook (aka "beanstalk", aka "space elevator"), it won't work. Whereas synchronous orbit of the earth is at the awkwardly high altitute of 22K miles, the equivalent for the moon is roughly 10X as high (as a result of the slower rotation of the moon about its axis).

      Plus there's this big planet that happens to be EXACTLY at the required altitude, so until it can be demolished (to make way for a hyperspace bypass) you're going to have a really hard time with this!

    3. Re:Moon Tether by cyclomedia · · Score: 1

      ahhhhhhhh, so earth's in geosync orbit around the moon! but wait, that makes the moon a planet and earth moon's moon! still, explains why we only ever see one side

      --
      If you don't risk failure you don't risk success.
  22. Back in the day. by PatTheGreat · · Score: 1, Interesting

    You know, it's vaugely surprising that they're even testing modules. Back in the day, when they were doing this the first time around, the lunar lander set down on the moon without ever being tested. They were depending on the relatively low gravity on the moon, and thus the lander could not actually stand up under it's own weight on Earth. So they couldn't test it under Earth gravity, and so they didn't test it at all.

    --
    Google: "All your data are belong to us."
    1. Re:Back in the day. by Anonymous Coward · · Score: 2, Informative

      No. It could stand it's own weight, and they did test it, both the concept on Earth (Lunar Landing Research Vehicle) as well as the actual vehicle in space on Apollo 9.

    2. Re:Back in the day. by HermanAB · · Score: 1

      No, there were many tests. Remember the 'flying bead stead' and the tests in space with earlier Apollo missions. Yes, I was around back then, a mere kid though...

      --
      Oh well, what the hell...
  23. Re:Hammer, Feather, Freefall on the Moon: Revisite by JohnFluxx · · Score: 1

    Uh, why would the moon feel a torque from a falling object?

  24. Re:Hammer, Feather, Freefall on the Moon: Revisite by Anonymous Coward · · Score: 0

    I had a professor that made this mistake once..

    draw a circle on the board. it is the earth. draw a bunch of arrows pointing down. that is the gravitational force vector.

    did you draw them down towards the ground or down towards the center of the circle you've declared is the earth? my prof did the former...

  25. Re:Moonshot awareness 101: Find+highlight all erro by feronti · · Score: 1

    Actually, they're proofs of concept, which means the contenders don't have to develop a vehicle to deliver the landers to the moon... they can simulate the lunar landing on earth. That makes the prize a lot more attainable for a private startup venture than requiring them also to build up a lunar capable launch infrastructure.

    As such, Armadillo would actually be an excellent contender for this prize, considering their current design is a really souped up lander in the first place.

  26. Not a mistake by Anonymous Coward · · Score: 0

    If we were talking about the moon's gravitational field you'd be right. But OP was talking about the combined gravitational field of the hammer and the feather. This is torque, no?

    1. Re:Not a mistake by Decaff · · Score: 1

      If we were talking about the moon's gravitational field you'd be right. But OP was talking about the combined gravitational field of the hammer and the feather. This is torque, no?

      The OP was not taking about the combined gravitation field, but the separate ones - the one from the hammer being stronger than the one from the feather, and the lack of symmetry creates a torque.

  27. Re:Hammer, Feather, Freefall on the Moon: Revisite by woolio · · Score: 2, Insightful

    The hammer is first to hit the ground.

    That may be, but the time difference between the hammer hitting the ground and the feather hitting the ground probably won't be observable to us....

  28. Re:Hammer, Feather, Freefall on the Moon: Revisite by Anonymous Coward · · Score: 0

    Who said it was supposed to be funny? My intent is to provoke discussion on the failings of our contemporary post-post-modern sort of "education" that sneers at any hint of relativism, even in physics. It's obvious from your tone that you were one of those who were taught, wrongly, that hammer and feather hit the ground together. You of all people could stand to open your mind a little bit.

  29. Re:Hammer, Feather, Freefall on the Moon: Revisite by captjc · · Score: 1

    You are an educated singularity idiot who
    can stupidily deny Nature's Harmonic 4
    simultaneous 24 hour days within a single
    rotation of Earth, or even make parody of
    the Cubic Creation Principle - but your
    mental ability to comprehend the greatest
    social and scientific discovery of all human
    existence has been lobotomized by the evil
    academic singularity bastards hired to
    destroy your ability to think opposite.

    Educators teach assumed math, but are too
    damn dumb, stupid and evil to know that
    until Word is cornered, Math is fictitious.

    http://timecube.com/

    Not to troll, but you totally sound like the Time Cube Guy...

    --
    Slow Down Cowboy! It's been 1 hour, 47 minutes since you last successfully posted a comment
  30. Re:Hammer, Feather, Freefall on the Moon: Revisite by Angry+Toad · · Score: 1

    The difference between the masses of the hammer, feather, and moon are so vast that the time difference may not be observable to the universe.

        I'd be interested in seeing the numbers.

  31. they had a test vehicle (picture on wikipedia) by r00t · · Score: 2, Informative

    Check this out:

    http://en.wikipedia.org/wiki/Lunar_Landing_Researc h_Vehicle

    There was a jet engine that lifts 5/6 of the weight, leaving lunar-like gravity effects (though not inertial effects) for the rocket engines to deal with.

    1. Re:they had a test vehicle (picture on wikipedia) by necro81 · · Score: 1

      they used this during the Apollo program, ostensibly to allow the astronauts to practice landing the LEM while still on Earth. They called it the flying beadstead. It was damn near a death-trap. Neil Armstrong - the guy who piloted the first real LEM landing (and subsequently, first man on the moon) - had to eject himself from it when it went out of control and crashed in a small fireball. I believe I heard that the "out of control" part was from the guidance system being unable to keep the jet propulsion always pointing down (acting against gravity).

  32. Hey, NASA can do cheap, too... by jpellino · · Score: 5, Interesting

    There's a story in "Chariots for Apollo" about the potential problem of hitting the descent stage engine bell on a uncharted rock. They had to consider that landing on a rock could damage the bell, push the bell into the ascent stage, etc... But they had neither the time nor the money to design and execute a test + spare LM to see what would happen. One day as they were moving the LM on a crane, the rig slipped, and the whole thing landed, engine bell down, on a pile of crates. No significant damage. One of the managers turned to the team and said someting like "You just got your million dollar test for free."

    --
    "Win treats sysadmins better than users. Mac treats users better than sysadmins. Linux treats everyone like sysadmins."
    1. Re:Hey, NASA can do cheap, too... by fm6 · · Score: 3, Insightful

      Jeez, they spent 30 billion 1969 dollars (about $160 billion in today's money), and they still had to cut corners?

  33. You are right by way2trivial · · Score: 1

    http://www1.jsc.nasa.gov/er/seh/feather.avi
    in the last frame you can clearly see there is enough room between the feather and the ground to insert your brain!

    --
    every day http://en.wikipedia.org/wiki/Special:Random
    1. Re:You are right by Anonymous Coward · · Score: 0

      Har har. If there's an error in my logic, feel free to point it out. I haven't bothered using Newton's equations to calculate the exact rate of acceleration the moon experiences towards the hammer, but the difference wouldn't be noticeable on video at broadcast definition and speed.

  34. Re:Hammer, Feather, Freefall on the Moon: Revisite by Anonymous Coward · · Score: 1, Insightful

    It's the principle of the thing. How many times have you heard the lie told that the hammer and feather fall together? How many times have you heard Newton's name invoked in promoting this egregiously lunocentric viewpoint? It's about time someone took a stand for hammer (feather) mechanics. The truth is that according to Newton's law of universal gravitation, the hammer and the feather fall to the ground at different rates.

  35. Re:Hammer, Feather, Freefall on the Moon: Revisite by petermgreen · · Score: 1

    The truth is that according to Newton's law of universal gravitation, the hammer and the feather fall to the ground at different rates.
    the truth is that newtons laws are just approximations of reality that happen to give good enough results in most situations.

    just how many significant figures are newtons "laws" known to be correct to in situations like that? i bet its nowhere near enough to answer the question of which will hit first.

    --
    note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
  36. Re:Hammer, Feather, Freefall on the Moon: Revisite by Anonymous Coward · · Score: 0

    Yes, but it is within Newton's theoretical framework that the absolutist lie is promuglated, printed glossy and rude for unquestioning acceptance despite this glaring internal inconsistency. Even within this framework, the statement that both objects hit the ground together is false.

  37. Re:Hammer, Feather, Freefall on the Moon: Revisite by Planesdragon · · Score: 1

    the truth is that newtons laws are just approximations of reality that happen to give good enough results in most situations.

    The truth is that everything in human perception is just an appoximation that gives us good enough results in most situations. Not just our formally described scientific notations, but realy basic things -- like the pixels you're reading now, the shape of the monitor that your eyes and brain put together, and the buzz of whatever sound is in the room now.

    (sorry, but people who piss on Newton are a pet peeve of mine. He wasn't wrong, he just didn't have any way to account for the forces that derive from the fabric of reality.)

  38. Bigger prize by Council · · Score: 3, Interesting

    Am I the only one who sort of wants them to say, "Hey! Anyone who goes and builds a moon colony gets all our money."

    Enough with this baby-step stuff.

    --
    xkcd.com - a webcomic of mathematics, love, and language.
    1. Re:Bigger prize by Anonymous Coward · · Score: 0

      How about the prize that Jerry Pournelle keeps suggesting? $5 billion for the first American-owned company that keeps 31 people alive on the Moon for 3 years and one day?

      As Jerry says, does anyone doubt this prize could be won?

  39. Re:Hammer, Feather, Freefall on the Moon: Revisite by Anonymous Coward · · Score: 0

    That's bullshit, Newton was wrong. This isn't some personal failing of his, just like it wouldn't be a personal failing of Aristotle to not know that the sun was powered by fusion--as you say, the information to be more correct was not available to him.

    Nevertheless, doing the best you can with what you have does not prevent you from being wrong, which is what he was.

  40. Bert Rutan to the rescue by LadyMayhem · · Score: 0, Redundant

    I'm just waiting for Bert Rutan to come back with a new and improved Space Ship One. The guy is amazing, his original desigh, which won the X-prize originally, already fits most requirements. I hope to see more from him in this next round.

    1. Re:Bert Rutan to the rescue by Doppleganger · · Score: 1

      "already fits most requirements"

      I'd assume the requirement it doesn't fit would be the "rocky, lunar-style landing site". I seriously doubt that even a heavily modified version of the "light the fuse, wait for it to burn out, then glide to earth" SpaceShip One would be suitable for the challenges of a lunar lander.

  41. Armidillo Aerospace by iendedi · · Score: 2, Informative
    Seems that Carmack and company like the bounty idea. I hope they are right, I would really like to see these guys bag one and get a win. From Armidillo's website:

    The lunar lander centennial challenge is our top priority this year unless something else pops up. We had a commercial opportunity that was exciting, but it seems to have fallen through. I'm not thrilled about landing on inclined, boulder strewn fields, but the payload and delta-V requirement are easier than we expected. Having two levels and consolation prizes is a good thing.

    As soon as we can show that the new engines can make two 90 second burns, the current vehicle should have level one in the bag. We will need software changes and a remote video system, but no other significant modifications. To take the big level two prize we will need a completely different landing gear arrangement, and the total performance may be pushing it a bit. If our new engine Isp is as good as it briefly looked, we may be able to modify this vehicle for level two, but we are expecting to have to use the upcoming 65" diameter vehicle, which will have a better mass ratio.

    It is unfortunate that the prizes can only be claimed at the X-Prize Cup, because that will encourage us to sit on the vehicles after they have been proven out, rather than flying them hard and potentially crashing them.
    --

    It is your personal duty to fight for what is right on a daily basis. Ignoring injustice is identical to approving
  42. Yeah well... by Have+Blue · · Score: 1

    I'm gonna go build my own lunar lander! With blackjack! And hookers! In fact, forget the lunar lander and the blackjack! Ahh, screw the whole thing.

  43. Re:Hammer, Feather, Freefall on the Moon: Revisite by Daetrin · · Score: 1
    That may be, but the time difference between the hammer hitting the ground and the feather hitting the ground probably won't be observable to us....

    You're probably correct, and the grandparent poster is clearly either having fun or is a total nutcase. However i think it's an important distinction to make. The whole "all objects fall at the same speed no matter their mass" thing always bothered me. My physics teacher stated that was the case but it didn't make intuitive sense to me. I understood that feathers fall a hell of a lot faster without air resistance but it seemed to me that if you dropped the moon on the earth (ie instantly killed its orbital rotation) that it ought to fall quite a bit faster. It took me longer than it should have to realize that although the mass of the moon would be canceled out just like for the feather or the hammer, that would be completly ignoring the other side of the equation in which the earth would fall towards the moon much faster than towards the feather or hammer.

    Really everything we know is a series of aproximations approaching the truth. Telling people a simpler "mostly true" version that covers their needs at the moment is fine, as long as you're willing to go on to the more complicated explanations as the need arises. All physics teachers/professors should be ready to explain the difference in the gravitational pull of objects on the earth if any students have trouble believing the first explanation (or that explanation should be offered by default, which is the better idea in my opinion.)

    Understanding that the difference in the "falling" rate was the difference between the gravitation pull of the feather and the gravitational pull of the hammer actually made the original statement make a lot more sense to me because i could see how one might technically fall faster than the other while practically the difference was irrelevant.

    --
    This Space Intentionally Left Blank
  44. For the love... by everphilski · · Score: 1

    ... they are doing it for the love. People competing for the prize are doing this because they can do it and because they want to do it. The prize is a consolation prize and yes helps recoup costs but that is about it. The original X-prize was $10M and Burt Rutan got $20M from Paul Allen in funding on top of materials he already had. Its a token prize to get people going, not meant to be a business decision. Doing it for love, not profit. The way the competition is set up there are already 2 serious contendors, Masten Space Systems and Armadillo Aerospace. They can modify existing hardware to compete without much difficulty.

  45. Its not 1st, 2nd, 3rd by GmAz · · Score: 1

    If I created the X-Prize, I would want several winners. Each of those projects will have something to contribute to the end product designed by NASA for an auctual Lunar trip. One may have a revolutionary liftoff thruster, while it may suck at landing while another might land extremely smoothly, but take off poorly. If you only accept one winner then your possibilities are limited while three has many more possibilities.

    --
    Click Click Bloody Click PANCAKES!
    1. Re:Its not 1st, 2nd, 3rd by Anonymous Coward · · Score: 0

      Also, there may be more than one way to get around on the Moon. Why assume monopoly? Just because it's what we're used to?

      Definitely reward all contenders who can do the job!

  46. Re:Hammer, Feather, Freefall on the Moon: Revisite by WheresMyDingo · · Score: 1
    The hammer is first to hit the ground.

    Anyone who denies this truth is a spatially absolutist lunocentric whose refusal to recognize the validity of hammer mechanics/experience places him wholly beyond the help of Galilean metaphysics.

    You are right for all the wrong reasons. See, to a hammer, everything is a nail. The other objects are much less motivated to hit their target. Be the hammer.

  47. Re:Hammer, Feather, Freefall on the Moon: Revisite by Zurk · · Score: 1

    the guy may be nuts but he is right about one thing --
    "until Word is cornered, Math is fictitious."
    the best description of the move from turing machine architectures that we're currently on to an NN-based architecture that i've ever seen. until we understand how language and NN based frameworks relate to turing architectures, we dont really understand ourselves or anything else for that matter.

  48. Re:Hammer, Feather, Freefall on the Moon: Revisite by Anonymous Coward · · Score: 0

    Telling people a simpler "mostly true" version that covers their needs at the moment is fine, as long as you're willing to go on to the more complicated explanations as the need arises.

    Perhaps, but you absolutely ought to explicitly say that you are doing so, and that the version you're telling them isn't applicable in all cases, and what those cases are.

    Otherwise you're just spreading ignorance.