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Space Technology

Space Tug to the Moon and Beyond 127

An anonymous reader writes "Andrews Space and SpaceDev, a contributor to SpaceShipOne, are building a cargo transport called SmallTug to travel to the Lunar L1 point using a Hall Thruster and running off of solar power. The final craft will be capable of attaching to and transporting satellites 85 percent of the way to the Moon for use in interplanetary missions. The launch date is scheduled for 2008 and it is being designed to be quite inexpensive. The Inquirer has more details."
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Space Tug to the Moon and Beyond

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  • Cheap (Score:4, Insightful)

    by hoka ( 880785 ) on Saturday July 16, 2005 @03:43AM (#13080093)
    $20 million is pretty darn cheap for the whole thing. I'm a little curious about the methodology for getting the thing into space. Correct me if I'm wrong but isn't this one of the teams that was competing for the X-Prize, which puts things into "space" but not into an orbital launch? Did the group adapt its developed technologies to a more rugged device that will be able to reach a large distance to the moon, or is the IPS that great at moving things into space?

    Man some days I really wish I had would have pursued a degree in rocket science.
    • I believe the cheapness is related to the fact that there are no fuel costs once earth orbit has been reached. Solar power gets the craft the rest of the way for free- but very slowly.
      • I believe the cheapness is related to the fact that there are no fuel costs once earth orbit has been reached. Solar power gets the craft the rest of the way for free- but very slowly.

        in space, there is no reduction of speed, the inertia will carry the object forward at the same speed. so, in addition to the solar panels, why not have some small and inexpensive fuel source for the start of the trip that gives a speed boost. the increase in speed will last the whole trip, unlike a car where it only lasts

        • that doesn't really work, even when you are in orbit, in order to increase your distance from the Earth you have to spend energy (the gravity still exists and pulls you down).

          So getting in orbit is just the first step. Escaping entirely from the earth's gravity is something different. I think this is the distinction between the first and second "cosmic speed". (I am not sure whether the term is correct in English)

          I am curious if you could use alternate types of energy to get into orbit. I mean, there are
          • ah, only 32 Mach, that's not even much for a solar powered airplane
          • The term in English for "cosmic speed" is, I believe, "escape velocity" - the speed required to escape from the Earth's gravity and go off into the cosmos, I suppose. The alternate term, however, is fascinating - what language is it from?
            • Romanian.

              And what do you call the speed necessary for an object to orbit at ground level?
              • And what do you call the speed necessary for an object to orbit at ground level?

                I'm assuming you mean maintain an orbit above the same spot on the ground at all times, as 'orbiting' at the level of the ground would be rather futile.

                We that type of orbit a Geosynchronous orbit, or if above the equator, Geostationary. I dont think we have an actual term for the speed required, at least I've never heard one.
            • The term in English for "cosmic speed" is, I believe, "escape velocity" - the speed required to escape from the Earth's gravity and go off into the cosmos, I suppose.

              There is an escape velocity for Earth, but there's also an escape velocity for the Sun. If you reach the escape velocity for Earth but don't reach the one for the Sun...I hope you brought lots of marshmallows because you're going to have one hell of a campfire.
      • Re:Cheap (Score:3, Interesting)

        by toddbu ( 748790 )
        Well, I think that there are three factors here that contribute to the low cost. First, there are no people on board to have to worry about. I don't know exactly how much NASA is spending to have the shuttle sitting on the pad right now, but I hear the term "millions" coming from the news media. One or two delays in manned spaceflight can come pretty close to paying for an unmanned mission.

        The second factor at work here is that the private space business doesn't have all the overhead that a government

        • Look at Spaceship One. No fancy designs, no high priced systems ...,and no real spaceship.
          • We all know you love the Shuttle and NASA ThreeeP and you are going to trash anyone and everyone who is trying to do something better and cheaper. You can trash SpaceShopOne all you want but the people who designed and built it accomplished their objectives, as modest as they were, and they did it with a small number of people, pretty much on budget and on schedule. That is indication of good engineering, versus the mess that is NASA, which is probably what the parent was alluding to.

            Scaled Composites' w
            • Wow -- another rant. Try thinking about your point first -- brevity is a virtue.

              Here's my point: comparing SS1 to the Shuttle is pointless. SS1 doesn't have the problems the Shuttle has because it doesn't have to have the energy to reach orbit, nor does it have to bleed off the energy to deorbit. And the X-15 did what SS1 did a half a century ago!

              Regarding the sensor problem, you really don't have a clue. Any vehicle using cryogenics will have a similar system. Do you have a better design? Burt and
              • Crap on it all you like, but it's still the best anyone has built.

                Not necessarily true. Even NASA admits that the Buran [nasa.gov] was a great achievement. (Ok, it was a direct shuttle ripoff, but it was still a different system.)

                Any vehicle using cryogenics will have a similar system.

                True. SS1 burned a modified rubber compound rather than a liquid fuel. I'm not sure that it will get you to orbit, but it will help you prove out a lot of other unproven systems. I can't wait to see what their final solution

                • Not necessarily true. Even NASA admits that the Buran was a great achievement.

                  I think this is stretching it. For example, the reason Buran could only do one orbit was because the Russians didn't develop an APU -- a critical piece of any large manned spacecraft -- which the Buran was not.

                  True. SS1 burned a modified rubber compound rather than a liquid fuel. I'm not sure that it will get you to orbit...

                  I can assure you it won't get you to orbit. Yes -- it's innovative and a great idea for a suborbita

                  • The Shuttle and ISS are our current and best ways of doing this.

                    Not really. A Saturn V/CSM stack are still the best technology that we have for the job. It isn't sexy, but it is a proven workhorse with eight successful missions (not including Apollo 13) and zero in-flight astronaut deaths across all 11 manned flights. I'm sure that you already know this, but it goes without saying that only Hollywood can send a Shuttle to the Moon.

                    I lost most of my interest in LEO after the deorbit of Mir. She was

                    • The Saturn V was a marvel. I was generally referring to currently available vehicles. Most people in the industry believe that the reliability of the Saturn V to LEO was probably less than that of the Shuttle. By this I don't mean launch record (13-0 to 111-2 I think), but rather a theoretical value. Admittedly, this is debatable and I'd be willing to concede the point.

                      As far as what we have learned, I'd have to start with something having nothing to do with either the Shuttle or the ISS -- operations.

                    • ... but that flight at Kitty Hawk had to happen first.

                      Hmm, interesting analogy. I would have used Mercury and Gemini for non-Earth operations. :-)

                      So let's take your list and see what we get:

                      1. long-term human physiology - done on Mir and Skylab. I believe that the current record is still held by a resident of Mir after his country disappeared while he was on orbit.
                      2. assembly of large components in orbit - Mir, and to some extent Skylab, ASTP, Apollo, Gemini and Hubble (admittedly with the help of the
                    • orbital power systems - proven out countless times by hundreds of government and commercial satellites. I'd argue that we'd taken a big step backward in this area since we no longer regularly fly RTGs.

                      I picked this one from your list as an example of some misinformation. The power systems on satellites don't come close to generating or managing the amount of power on ISS or that will be needed on planetary missions. Moreover, RTGs are tiny -- both in terms of power output, size, and efficiency. The ISS

                    • I couldn't resist saying more.

                      Human physiology -- while Mir cosmonauts hold the record for duration on Mir, they did very little for furthering human physiology studies. Not so on ISS.

                      Assembly of large components -- yes, the early missions were critical for fundamental knowledge, but Mir and ISS have presented us practical issues, like mechanisms, reliability, logistics, etc.

                      Life support systems -- I haven't read Sy's book but it seems odd to be dissing the current crop of NASA engineers. Most of them
                    • Why not support the team that's on the field?

                      Because the current team has done little to build confidence, and I'm not willing to throw good money after bad. If you think that the current NASA management team doesn't suck, just compare the response of the guys on Apollo 1 to those responses of the guys overseeing Columbia. Read any book from an Apollo-era flight controller and they'll tell you that they played a hand in killing their crew. After Columbia, it was a mad scramble for everyone to cover the

                    • "Human physiology -- while Mir cosmonauts hold the record for duration on Mir, they did very little for furthering human physiology studies. Not so on ISS.'

                      I'm sure there must be some examples what exactly have we discovered about physiology on the ISS or Shuttle that justifies the $100 billion price tag. If there was some discovery big enough to justify the price tag, I'm shocked I haven't heard about it. Was it, "its a good idea to exercise if in zero G"? I could have figured that out for a lot less mo
                    • I recommend picking up a copy of SMAD [amazon.com] and reading section 11.4 starting on page 407. Pay real close attention to table 11-33 which compares current power technologies. Also check out section 10.3 on design budgets, including the power budget. You'll see that the power budget is where all the "heavy lifting" is done when it comes to power management. Building a slightly larger set of solar panels [boeing.com] doesn't help you at all on deep space missions. It all depends on the power budget, and the Shuttle and ISS
                    • they played a hand in killing their crew.

                      This comment is beyond poor taste and is simply cruel.

                      These people inspire no confidence.

                      You know nothing about these people.

                      Could you elaborate please?

                      What other system could have launched and recovered it?

                      Are you really that naive to believe this?

                      I guess so -- if you do the energy calculation, getting to LEO takes about 83% of that required to achieve escape velocity.

                    • This comment is beyond poor taste and is simply cruel.

                      I didn't say this. Chris Craft, Gene Krantz, and several others did in their autobiographies. Try reading them sometime.

                      You know nothing about these people.

                      Not personally, but I see their handiwork. I'm sure that they're really nice folks, but I'm not willing to turn over the keys to the bank vault without some demonstration that they can manage the pot of money.

                      What other system could have launched and recovered it?

                      At 11 tons, there wer

                    • I hate replying to my own post, but I really hosed some names here. It's Chris Kraft [amazon.com] and Gene Kranz [amazon.com]. I knew they looked wrong and forgot to fix them prior to posting. Sorry for the errors folks. I still hope that you read the books.
              • "And the X-15 did what SS1 did a half a century ago!"

                Thats a pretty petty way to dismiss a great accomplishment. Again the key thing SS1 accomplised was it succeeded at what it was designed to do, on a budget and and a schedule and that is something NASA is completely incapable of at this point.

                The feathered wing is a very innovative approach that was a vast improvement over the X-15. X-15 reentry was very hot and very dangerous. The SS1 reentry is cool enough they can use composites instead of Titaniu
                • Bottomline is SS1 adheres to KISS which is usually good engineering.

                  I don't wish SS1 any bad luck, but every flight has been lucky. Each time, they barely pulled out of huge attitude departures. They collapased a landing gear on landing. They never came close to staying within their designated airspace or on their planned flight path.

                  • Stop shedding the crocodile tears, you back hand Rutan, SpaceShipOne and Scaled Composites in every post you mention them, right after you say how much you really like them, like you just did AGAIN.
                    • Those were just facts -- I don't see any "back handing..."
                    • "Those were just facts -- I don't see any "back handing..."

                      "They never came close to staying within their designated airspace or on their planned flight path."

                      Well its a subject for debate but I don't think these are really the facts, you are bending facts to the point they are more mud slinging and back handing.

                      One of the last envelope expansion flights was of trajectory but that was only because the pilot was being conservative about a potential problem and delayed the burn.

                      The first flight in to spa
            • And of course the Shuttle has spent nearly 5 years grounded.

              How does 2 1/2 years become 5?

              • "How does 2 1/2 years become 5?"

                For someone who keeps telling us how superior your knowledge and intellect is you sure aren't very bright.

                The shuttles were grounded from Jan 28,1986 until Sept 28, 1988 after the Challenger explosion

                5 = 2 1/2 after Columbia + 2 1/2 after Challenger

                Of course the Challenger grounding is more like 2 3/4 years. Of course the Shuttles are still grounded now, and if NASA misses this window they are going to be headed for 2 3/4 years and counting again, so it could be 5 1/2 ye
                • I'm still waiting for you to point to a vehicle (not a dream) that does 1/2 of what the shuttle can do. Something the shuttle has done over a hundred times.
                  • Nice, instead of admitting how stupid your post was, just change the subject.

                    "I'm still waiting for you to point to a vehicle (not a dream) that does 1/2 of what the shuttle can do."

                    Thats easy Saturn V. It did ten times more than the Shuttle has. Thank you Richard Nixon and you assholes at NASA for scrapping it and turning the last one in to a rusting lawn ornament. If we had stuck with that stack and made incremental improvements we would be way ahead of where we are today. CEV is going to take years
      • How exactly does solar power help with propulsion? I thought you need to throw stuff out the back in order to move forward.
        • Re:Cheap (Score:1, Interesting)

          by Anonymous Coward
          Without having read the article I can think of two obvious ways.

          1) Solar sail type technology where the photons provide the reaction mass.

          2) Ion drive tech where the reaction mass is used much more effectively (>1000X).

          I would lean towards the latter case. The tug could get its reaction mass in several ways:

          a) Massing missions. Every N-th launch is a remassing mission. This is very straightforward but means that most of the time the tug is carrying around far more mass than it needs.

          b) BYOM.
        • Generally, you do need to "throw stuff out the back." Solar electric merely refers to the fact that solar power is used to energize particles so that they shoot out the back at a very high speed. The extra high speed they shoot out means that you can use a lot less propellant mass in order to provide a bit of forward momentum to the rest of the craft.

          This link [wikipedia.org] provides more details.

    • Re:Cheap (Score:4, Interesting)

      by helioquake ( 841463 ) * on Saturday July 16, 2005 @04:12AM (#13080141) Journal
      The company's objective is to research, design and develop this "smalltug" spacecraft, not (guessing based on the articles) about putting it into the orbit. Marshall would most probably pick up the bill for that.

      Nontheless, $20mil is a good price tag. I hope Andrews Space does succeed in this (and if it doesn't, well, then it won't get any more than the first phase of the 1.25mil budget...I wish we can slap this kind of thing onto NGST, Boeing or TRW).
    • Re:Cheap (Score:3, Informative)

      by tonsofpcs ( 687961 )
      L1 is the first Lagrange point of the moon, the point between the Moon and the Earth where the perceived gravitation is negligable
    • When somebody says "Space Tug", what comes to mind is a space version of the powerful little boats that haul barges around -- something compact which moves a lot of mass around.

      The system, however, is called "Small Tug". It only costs $20 million becuase it's a technology demonstration. It's not meant to be practical, it's meant to show that it's principles of operation are sound and to get experience with the technologies involved. It's still a bargain, but if we could build something that would haul
  • by lorelorn ( 869271 ) on Saturday July 16, 2005 @03:43AM (#13080097)
    The first phase of the mission will be to measure the radiation environment between the Earth and the Moon.

    Part of me wonders why this is not known in detail already, plus wouldn't it be related to solar activity anyway? Solar wind and so forth.

    They need to know though, since the trip to L1 will take 1 year.

    I remember reading in New Scientist about a decade ago now that you can get to the moon using very little energy- an orbital transfer basically. Catch is, it takes 2 years to get there.

    • Send cargo on the slow boat, then send people in a faster craft when everything they need has arrived.
    • Minimum energy for an orbital transfer is via a Hohmann (sp?) transfer, and takes less time than one orbit of the outer body. Basically a deltaV at periapse of the lower orbit, then another at the apoapse of the transfer ellipse, which is the radius of the new (circular) orbit.

      The two year scenerio is probably a Mars mission, as the proper transfer will send you out to intersect the mars orbit, but a failure to complete the final burn at Mars will return you to earth orbit, at earth, in 2 years.
      • by Anonymous Coward
        check out http://en.wikipedia.org/wiki/Interplanetary_Superh ighway [wikipedia.org] for an even longer transfer than Hohmann with lower energy
        • Yes, you're correct. I was referring to impulse delta-V transfers in two-body mechanics.

          I was being impatient, the good, card carring American citizen that I am. (If I had all the time in the world, I'd walk to work instead of driving a big SUV and accelerating from stop sign to stop sign at full throttle ;-)

      • It's worth considering the source of the energy you need. If you are using a typical solid or liquid propellant, then the Hohmann-type trajectories are optimal. Of course you don't get these more than every 23 months, and some opportunities are better than others because of relative inclination and planetary orbit eccentricities (this year's MRO launch is particularly nasty). Anyway, if you are using something like solar propulsion then you get 'free' energy and a completely different launch/arrival spac
    • I will take a guess that the answer to your first question is implied by your second question.

      Apollo, if it carried radiation instruments, only gave us 3-day samples. We still need to know likely worst-case values over the course of a year. Then there's enough data to correlate with sunspot numbers and whatnot, to make forecasts possible.
  • Why stop? (Score:2, Interesting)

    by Anonymous Coward
    85% Why stop there? If it can get to 1.5 million km at L1 why can't it go all the way to 0.35 million km for the Moon? It seems to me that almost any spacecraft that can get to the 85% of the Moon in a finite period of time can make it all the way to the Moon.
    • I believe it's because past L1, there is more influence of gravity from the moon than from the Earth, so it's rather inefficient for a tug to take something all the way to the moon and have to fight against its gravitational pull, thus expending full is doesn't need. It's not that it can, it just doesn't want to.

      I could just be totally wrong, though.
    • Re:Why stop? (Score:5, Informative)

      by MGDruss ( 729168 ) on Saturday July 16, 2005 @06:17AM (#13080366)
      "85% Why stop there? If it can get to 1.5 million km at L1 why can't it go all the way to 0.35 million km for the Moon? It seems to me that almost any spacecraft that can get to the 85% of the Moon in a finite period of time can make it all the way to the Moon" Because the purpose of this mission is to travel using the Interplanetary Superhighway. This is a very slow, but extremely energy efficient (almost energy free) way of travelling round the solar system. There are Lagrange points between any two bodies in the solar system, these are points where the gravitational forces balance out. Some of these are stable, but some are not and drift around. The Interplanetary Superhighway is the map of these drifting ones. Basically, you get to a drifting Lagrange point and you are on a highway which connects to any place in the solar system! It just takes ages to get anywhere though.
  • 85 = 5*17
    2008 = 2*2*2*251
  • SmallTug? (Score:2, Funny)

    by matt21811 ( 830841 )
    Ha, could they come up with a more porno sounding name?

    Of course it comes as no suprise that "Andrews Space is a privately held company"
    • One speculates that once operations are in order, they will refer to work that the SmallTug gets to be a 'tug job'. In addition, you could have such services as 'a rub and a tug', where the SmallTug rides along the edge of a target and looks for a place to attach, or 'a tug and a blow', where the tug would tow out a solar sail and let it be blown away by the sun. Use your imagination and I'm sure you can see many more tug services.
  • Hall Thruster (Score:4, Interesting)

    by Planetes ( 6649 ) on Saturday July 16, 2005 @03:49AM (#13080109)
    It should be noted that hall thrusters are extremely low thrust but high ISP. This is effectively an ion drive. This means that it's a relatively slow method of doing orbital transfers. In other words, don't expect this thing to drag the satellite L1 in half an hour.

    Our nanosat-4 project is using a PPT although we considered an MET for a while. We have to maintain formation flight between three satellites which requires high thrust/quick burn types of thrusters. That burn time ruled out the MET.
  • "off of" (Score:2, Insightful)

    by Anonymous Coward
    If we can't spell correctly here, can we at least make English the primary language.
  • by Anonymous Coward on Saturday July 16, 2005 @03:59AM (#13080124)
    FYI:

    http://en.wikipedia.org/wiki/Interplanetary_Superh ighway [wikipedia.org]

    Once you are on the IPS, it's pretty easy to get where you want with very little fuel expenditures. What I'd like to know is how they plan to get there, since in order to get to the nearest IPS orbit, you probably still need amount of energy, comparable to what it takes to get into LEO. SpaceShipOne lacked the capability to get into LEO by a long shot.
    • If you can fall off a Lagrange point and drift into other locations, then there should be windows when you can drift from given locations back to a Lagrange point.

      But yes, you do need to dig yourself out of the gravity hole we're in. Once in LEO you could spiral out with a slow efficient drive like a solar sail or ion propulsion, but LEO is the price of admission.

    • Once you are on the IPS, it's pretty easy to get where you want...

      Unfortunately, most of humanity is not immortal -- and to get between most useful places using this interesting, but impractical IPS requires long durations -- often in excess of centuries.

      Bottom line, you still need lots of energy on trajectories that are closer to that of Hohman Transfers.

  • Own a part of this. (Score:1, Informative)

    by Anonymous Coward
    Andrews isn't, but SpaceDev [spacedev.com] is a publicly traded company [yahoo.com].

    Disclaimer: I own a few shares that I bought a little while after the SpaceShip One media blitz had died down. Scaled Composites is a private company, but SpaceDev builds their rocket engines [spacedev.com]. For me it's a long term bet - I may not win, but the sheer coolness of putting money in on this seemed like a good idea at the time.

    Since I work in a completely unrelated field [entertainment], get horribly sick on a rollercoaster and would never see space wil
  • Modularity (Score:3, Insightful)

    by James A. D. Joyce ( 742507 ) on Saturday July 16, 2005 @05:01AM (#13080227) Homepage Journal
    How well could it interface with existing satellites? It's all well and good having a cheap and convenient space cargo ship, but it's pointless if it only attaches properly to a particular proprietary type of craft.
  • Naming rights... (Score:3, Interesting)

    by John Seminal ( 698722 ) on Saturday July 16, 2005 @05:25AM (#13080271) Journal
    Someone made a joke about calling it SmallTug. I laughed and thought "well, at least it is not called TugJobs", which got me thinking in my usual demented manner...

    Ox might have a copywrite lawsuit. Or maybe they would settle for Ox advertising on the side of the spaceship "Brought to you by BangBro's".

    Come to think of it, I am suprised Nasa has not sold naming rights yet. If Comisky Park can get 30 million to change their name to US Cellular Field, how much could NASA get to change the name of their space shuttle from Challanger to the Anhiser Bush Space Shuttle. Maybe they could even get a 30 second advertising clip of the astronauts floating in space drinking a cold refersing budwieser. Nike could be next in line, having an exclusive contract to provide all NASA shoes. It could be like what Nike did 10 years ago in college basketball when they paid 7 or 8 of the best college program universities millions of dollars to force their athletes to wear nikes as part of the uniform. When the final 4 came, all 4 universities were in contracts with Nike, and all the basketball players were wearing Nikes. Every 3 hour basketball game was free advertising for Nike, as every basketball player was wearing their shoes. Well, in space, there is only one team, and it would be lots of free advertising when they are interviewed. Maybe Kennith Cole could pay a couple million to help design the artistic look of the new space suits.

    With all the different industries that could contribute money for advertising, I wonder how much NASA could get per year? 100 million dollars? 250 million dollars? If you were IBM and you were smart and wanted to keep OS/2 alive, what better advertising could you have then to have your OS used on the space shuttle, to have advertising?

    Just imagine every chemist, biologist, mathematician and physicist in the USA, dressed in Nike Moonwalkers, wearing Kennith Cole Space Pleather jackets, with their IBM laptops running OS/2, and drinking a coca-cola before thier big exam or buisness meeting because it is what the astronauts drink before a critical mission.

    • Actually, they drink tang.
      • I'll believe you. If they drank coke just before a space flight, I don't know what might happen to the accumulated gas in their stomachs. Don't like to think about it either.
        • They might get shaken up, but I don't see what else would happen.
          • Hum. Well, taking it as a given that there is considerable vibration (I'm ready to consider it, for one) during a shuttle launch, and that the thing rotates on its vertical axis, I'm ready to suggest the following experiment. Take 2 bottle of coke, let them stand at room temperature for a couple of days - just so everything is stable. Put them in the 'fridge if you want - though this makes the experiment less realistic. Now open the first bottle - you should find that it behaves quite normally. Now tak
    • Sounds like a horrid orgy of capitalism's worst points to me.
      • it may well be, but it would certainly give NASA the funding that this government is holding back on. But of course, it would have to be a private company and not govt. affiliated for that kind of thing.
  • Notice the article doesnt give any useful details. Solar-powered ion-thrusters have been studied since 1959 or so. They are inextricably limited to providing really teeeeensy amounts of thrust. The only big winning point is you don't need much reaction mass to throw out, as the stuff goes out really quickly. Downside is you don't have much power to work with, and you can't make more than a very tenuous cloud of ions (they repel each other).
  • My name's tug; can I call the ship mini-me? And... what would this be used for, exactly
  • Is this tug going to be reusable? I mean, will it come back to low earth orbit after it drops off its payload to pick up more propellant and another satellite?

    NASA has looked at similar things, though none have been built yet. http://www.grc.nasa.gov/WWW/RT2001/6000/6920verhey .html [nasa.gov]
  • A worrying number of space systems were invented by science fiction writers...
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  • ..doesn't this suggest a major need for an orbiting cargo facility of sorts? If this and technology like it were to be become more prevalent (whether for placing satellites in lunar orbit, at the lagrange points, or simply in higher orbit) then surely it would make sense to have an orbiting queue to hold a satellite while waiting in line for the next slow tug to come back on duty. (earth-->LEO+docking@cargo-->L1,etc).

    Low earth orbit and beyond are a crowded place these days, and the placement of s

  • "Marcus Garvey". Make sure to spray the control console bright pink too.
  • actually, i wouldn't expect anything from NASA, or any other space agency on this planet, to present anything to the public that would floor them, until they get this 'gravity' thing under control. Once we've got that, you can expect to see insanely cool things (and practical too, for our day to day lives that is). Keep in mind, so far, we know that it exists, and that we're all subject to it. Why matter tends to do that in large clumps? So far, its only theoretical. Mass is a tricky thing. I know someone

In any formula, constants (especially those obtained from handbooks) are to be treated as variables.

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