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Space Science

A Deep Space Primer 118

Posted by michael from the don't-forget-the-freeze-dried-ice-cream dept.
phil reed writes "With the latest Mars missions still in the news, people might be curious about what it takes to actually run a deep space mission: how a spacecraft is designed, how the communications are handled, what kind of project management is in place to make it all work. The Jet Propulsion Laboratory has a primer online that gives broad general coverage of all aspects of putting a satellite into orbit and how to manage it once it's there. Fascinating reading, with lots of links to more detail."
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A Deep Space Primer More

A Deep Space Primer

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  • No thanks (Score:4, Funny)

    by Anonymous Coward on Friday February 06, 2004 @07:28PM (#8207849)
    I am waiting for Build your own space mission For Dummies to come to my local B&N.

    • Re:No thanks (Score:1, Informative)

      by Anonymous Coward
      Whoever wins the X-Prize [xprize.com] will write it.
    • i think reading Douglas Adams' The Ultimate Hitchhiker's Guide would be more fruitful and entertaining.

    • Re:No thanks (Score:2, Interesting)

      by photonX ( 743718 )
      I remember a Mad Magazine piece when I was a kid (mid-Sixties, I guess) titled something like: "Kids: build your own 707!" It used four of those cylinder-type Electrolux vacuum cleaners for engines, presumably with really long extension cords...If we could only build a *really* big catapult, then the sky's the limit!

      Seriously, it's easy to forget that just a century ago we were literally a horse-and-buggy civilization, and how amazing it is that we can make these things work at all. I was talking to a yo
  • It is so mind boggling when you think aabout the actual costs to make one of these mars rovers and how much it costs to send it up in space. After all these are basically disposable because they most likely will never get them bac unless we make a succesfull manned mission to mars.

    • Re:Its Mind Boggling (Score:5, Insightful)

      by morcheeba ( 260908 ) * on Friday February 06, 2004 @07:42PM (#8207966) Journal
      Would you really want them back?

      The objective of these missions is to learn more about mars.. if we were just interplanetary joyriding, then, yes, I'd want the rover back -- but that's not the case here.

      Besides, the rovers are only a small portion of the cost of the mission - even if we could magically get these back for free, it would be worth the effort to build new rovers that incorporate the things learned on previous missions and provide new and different capabilities.

    • Re:Its Mind Boggling (Score:5, Insightful)

      by Anonymous Coward on Friday February 06, 2004 @07:49PM (#8208013)
      If you think the cost is mind boggling, you haven't seen what it would cost to if they were designed to return to earth when they were done.

      • Re:Its Mind Boggling (Score:1)

        by Anonymous Coward
        But they would make a heck of a trophy for the winner of X Prize XVII: Homebuilt Rocket to Mars.

  • JPL (Score:4, Insightful)

    by miketo ( 461816 ) <miketo@nRABBITwlink.com minus herbivore> on Friday February 06, 2004 @07:30PM (#8207865)
    There are a lot of smart, dedicated, and *unsung* heroes at JPL. NASA tends to get all the celebrity, but JPL deserves it just as much. Thanks to all who are working on our Mars missions and the various other missions that are increasing our knowledge of our universe and ourselves.
  • Set it, and Forget It!

  • so close! (Score:5, Funny)

    by fjordboy ( 169716 ) on Friday February 06, 2004 @07:31PM (#8207876) Homepage
    From the Primer:
    The BSF is intended to be used online via the worldwide web (http://www.jpl.nasa.gov/basics). There are interactive quizzes to let you check your own progress; no records are kept. No academic credit is offered for completion.
    Bummer...just when I thought I could get academic credit for cruising the web...

  • Tweaking, JPL Style (Score:5, Funny)

    by lpangelrob2 ( 721920 ) on Friday February 06, 2004 @07:32PM (#8207880) Journal
    And in the animation section...

    Too many windows on your screen may tax computer "power" causing animations to run too slowly, but if they're too fast, you might choose to run additional programs to use up computing power and slow the animations.

    So it looks like JPL's also providing a newbie guide on "tweaking your system." :-)

    I'd like to see how someone with a 3.0 GHz PC handles this...

    • Re:Tweaking, JPL Style (Score:4, Funny)

      by enosys ( 705759 ) on Friday February 06, 2004 @07:52PM (#8208038) Homepage
      I haven't had to deal with this issue since Wing Commander. I would have thought JPL would be capable of making software that plays animations at the same speed on all computers that are fast enough for it.

      Then again if they forget to handle filesystem full errors on Mars rovers who knows... ;)

      • Off topic but amusing let's see if the moderators think it balances out!

        When I was in College I had a brand new and blinding fast 386/SX-16 that I wanted to play Wing Commander on. Alas it was designed to be run on a 4.77Mhz XT and I could not control the ship at the blinding speed. However I quickly thought to load up the new at the time Windows 3.0 and play Wing Commander in a dos box from that. This worked flawlessly and led to my tag line of, 'Windows, the 8086 Emulator for your 80386!'

  • Warning (Score:5, Funny)

    by savagedome ( 742194 ) on Friday February 06, 2004 @07:33PM (#8207892)
    They forgot the statutory warning.

    DO NOT attempt this at home

    • Re:Warning (Score:4, Funny)

      by Zocalo ( 252965 ) on Friday February 06, 2004 @07:55PM (#8208064) Homepage
      Ah, but the beauty of this is that if you did actually did try it at home, then one way or another you wouldn't be at home for long. Depending on how successful you were you would be leaving in either a deep space probe, ambulance or meat wagon.

      • Ah, but the beauty of this is that if you did actually did try it at home, then one way or another you wouldn't be at home for long. Depending on how successful you were you would be leaving in either a deep space probe, ambulance or meat wagon.

        Or if your failure is spectacular enough you just might be evaporated, leaving as a wisp of smoke on the breeze.

  • Nice to see. (Score:5, Insightful)

    by Anonymous Coward on Friday February 06, 2004 @07:35PM (#8207904)
    It's nice to see that space exploration has come so far in my lifetime. When I was a boy during WWII, travel to Mars, even by machines, was just science fiction, and the stuff of magazine covers. Most of the world's scientists and engineers were at work developing weapons of war, and for some of them, rockets, high altitude airplanes, etc. were allowed projects that laid the foundation for today's space miracles.
  • On the first quiz on the Solar System, on the questions that you can select multiple answers it keeps telling me I didn't select any answer, and marks it as wrong.

  • How it should have started... (Score:5, Funny)

    by el-spectre ( 668104 ) on Friday February 06, 2004 @07:46PM (#8207990) Journal
    "In the beginning the Universe was created. This has made a lot of people very angry and been widely regarded as a bad move."

    R.I.P. DNA

  • Long-feedback cycles and good design (Score:5, Insightful)

    by G4from128k ( 686170 ) on Friday February 06, 2004 @07:48PM (#8208007)
    This type of careful planning and careful execution is useful for any endeavour with long or expensive feedback cycles. That includes terrestrial tasks like creating nuclear powerplants. Too many engineers have a hands-on, tweak-and-see hacker mentality, where projects like Mars rovers, nukes (and many other projects)need to work as planned right out of the box.

    A former boss and engineer had a great story about his early job experience designing circuits for a guided missile. He showed his first circuit design to the boss and the boss noted all the little adjustable pots in the circuit. The boss simply said, "Are you going to fly with that missile to tweak all the pots?"

    Although simulations, testing, and prototyping are great, truely great engineering just works because it was designed correctly from the beginning to just work.

    • Re:Long-feedback cycles and good design (Score:5, Interesting)

      by steveha ( 103154 ) on Friday February 06, 2004 @08:07PM (#8208160) Homepage
      You are absolutely right -- for the current way we do space.

      But I look forward to the day when we can develop space hardware the same incremental way we develop other things. When flying into space is as cheap as flying to Australia, we won't have to have massive, incredibly careful engineering projects. We can just try stuff and go with what works.

      P.S. Am I naive to think we can go to space as cheaply as going to Australia? No. We can't do it with the Space Shuttle, which requires many man-years of labor to rebuild after each flight. And we can't do it with expendable boosters, which are completely destroyed when you use them. We will need actually reusable spacecraft. I fear that NASA is no longer, as an organziation, able to build them, but someone else will. Go Xcor! Go Armadillo Aerospace! Go... anyone building these things.

      steveha

      • Cheaper future vs. the vicious cycle of cost (Score:4, Insightful)

        by G4from128k ( 686170 ) on Friday February 06, 2004 @08:21PM (#8208264)
        But I look forward to the day when we can develop space hardware the same incremental way we develop other things.

        Absolutely! I look forward to a range of advancements such as lower cost access to space (personal fav is a space elevator), truely routine manned space operations, and better adaptive/autonomous robotic systems.

        Yet I fear that the foreseeable future (next 20 years at least) will be dominated by rare and expensive space projects in which every lauch counts and every EVA-hour is carefully scripted and rehearsed.

        Its a vicious loop, really. Because space is expensive, space projects are very carefully planned and executed. And because space projects are so carefully planned and executed, they are expensive.

      • But I look forward to the day when we can develop space hardware the same incremental way we develop other things. When flying into space is as cheap as flying to Australia, we won't have to have massive, incredibly careful engineering projects. We can just try stuff and go with what works.

        Except... Flying to Australia is cheap because the aircraft you fly on was a massive, incredibly expensive engineering project. It requires guarunteed performance and near absolute reliability, and that comes from engi

        • Flying to Australia is cheap because the aircraft you fly on was a massive, incredibly expensive engineering project.

          Perhaps so. Of course, what I actually said was that once we have cheap access to space we can "try stuff" in space.

          But also of course, we can use incremental development (build and test, then build and test some more) to get our reusable spacecraft. Yes it requires engineering; I never said otherwise.

          The important difference between a Boeing 747 and a Space Shuttle is that it takes an

    • Re:Long-feedback cycles and good design (Score:5, Insightful)

      by iggymanz ( 596061 ) on Friday February 06, 2004 @09:15PM (#8208684)
      Not true. To design something very complicated like an aircraft or Mars rover there are *many* models and experimentation done, because almost all textbook equations are only approximations of reality. Since you used example of missile, there is NO WAY to model the turbulence, forces, torques, etc. involved with a real missile in flight, though we are getting better at approximating them. Any missile design will have many man-years of "twiddling, tweaking, and hacking" in the evolution of its design.

      To use an even simpler exmple, what if one burns 2.00000 moles of hydrogn and 1.00000 moles of oxygen, how much water is produced? If you answer that question based on what you learned in freshman chemistry you'd be wrong. In the real world, reactions never go to 100%, reagents aren't pure, and other chemicals besides water (like hydrogen peroxide) would be produced. And the ONLY way to know how much water would be produced under given conditions would be to actually do it. And then, you'd find for repeated experiments the amount wouldn't quite be the same!

      And finally, I'd point out that when systems fail aboard a Mars rover, they're very much back the realm of hacking, tweaking and fiddling.

      • Tweaking vs. robustness (Score:4, Informative)

        by G4from128k ( 686170 ) on Friday February 06, 2004 @09:50PM (#8208907)
        Not true. To design something very complicated like an aircraft or Mars rover there are *many* models and experimentation done, because almost all textbook equations are only approximations of reality.

        Excellent point. My heat transfer prof warned us that the equations in the textbook would get answers that had as much as 30% error (if you were lucky). And, IIRC, some theories in material science only yield answers that are within an order of magnitude (factor of 10) of the true value.

        But what I was alluding to was robustness -- designs that aren't affected by approximation errors (or the inevitable measurement errors when you build and test a prototype). Some of this is a matter of factors of safety (overdesign) but the truely great engineers create designs that are insensitive to encountered variations. At some level the ability of the Rover team to correct the recent faults represents this type of robustness. Yes, they are tweaking and hacking, but it was only because of a robust, remotely fixable design that let them do this.

  • how the communications are handled (Score:3, Interesting)

    by iminplaya ( 723125 ) on Friday February 06, 2004 @07:50PM (#8208025) Journal
    veerryy sloowwly. What is it? 20 minutes to mars and back? Light speed won't cut it when we talk about going anywhere farther than the moon. At our current level of comprehension, it's just not practical to go any father than Mars. We need to dream up something entirely different. Something that works like a very long tube filled with ping pong balls for example. Push one into one end and one pops out the other instantly, no matter how long the tube. I'm sure somebody has thought of this and has a name for it, but I sure don't know what it is.

  • Misleading title... (Score:5, Insightful)

    by pla ( 258480 ) on Friday February 06, 2004 @07:55PM (#8208062) Journal
    Humans have yet to perform any "Deep space" exploration.

    The Voyager missions come the closest, but still remain fairly near home, on any meaningful interstellar scale.

    The linked article discusses interplanetary exploration. Quite a bit of a difference.

  • Deep Space? (Score:5, Interesting)

    by glrotate ( 300695 ) on Friday February 06, 2004 @07:59PM (#8208093) Homepage
    Is Mars Deep Space? Shouldn't that term at least be reserved for regions outside the solar system? Or is that "Outer Space"?

    • Re:Deep Space? (Score:5, Informative)

      by Detritus ( 11846 ) on Friday February 06, 2004 @08:53PM (#8208527) Homepage
      Most NASA satellites are in low-Earth orbit. Some are in geosynchronous orbit, like TDRSS. Some, like satellites that study the solar wind, are in unusual orbits that take them far away from the Earth. JPL handles the satellites that leave the vicinity of the Earth and the Moon.

      NASA's satellite tracking and communication systems are adequate for spacecraft in the vicinity of the Earth and the Moon. They are not good enough to handle spacecraft at larger distances. That is why JPL's DSN (Deep Space Network) has much larger antennas, super low-noise preamps, and higher performance receivers and transmitters. Their systems are designed and optimized to work with very weak signals.

      The difference between near space and deep space is more a matter of operating conditions than of geography.

      • NASA's satellite tracking and communication systems are adequate for spacecraft in the vicinity of the Earth and the Moon. They are not good enough to handle spacecraft at larger distances. That is why JPL's DSN (Deep Space Network) has much larger antennas, super low-noise preamps, and higher performance receivers and transmitters.

        You do know that JPL is NASA?
        • It's a joint operation of NASA and CalTech. It's simplistic and incorrect to say that it is just another part of NASA. There are NASA standards and there are JPL standards. They cooperate and interoperate but they are distinct in many ways.

    • Like you, I thought that "deep space" meant between solar systems (or at least outside our own). People seem to be using it as "beyond low earth orbit."

      Sigh. Another technical term gets co-opted and perverted.

  • Broken Quiz? (Score:3)

    by grantdh ( 72401 ) on Friday February 06, 2004 @08:44PM (#8208445) Homepage Journal
    Maybe it's my browser but I got kinda disappointed with the first quiz - it keeps saying "Wrong, no selection made." on each of the checkbox responses - no matter which ones I check.

    I couldn't imagine JPL putting up a web quiz that didn't work - I mean, that'd be like having different modules in a probe using different units of measurement.... oh, yeah, oops... :)
    • Yes.

      Here are my results:

      Your score: 57%

      There were 15 possible choices. Results for each choice you selected are shown below. Use your browser's BACK function to return to the quiz.

      Question 1.01:
      Right

      Question 1.02:
      Right

      Question 1.03:
      Wrong, no selection made.

      Question 1.04:
      Right

      Question 1.05:
      Wrong, no selection made.

      Question 1.06:
      Right

      I went back to the quiz and sure enough 3 and 5 were answered then I tried to reset the quiz several times to no avail. More troubling is the fact that with 4 of 6 cor

  • not quite deep space (Score:4, Interesting)

    by ryanw ( 131814 ) on Friday February 06, 2004 @09:10PM (#8208643)
    I would see people telneting into satalites from time to time while I worked at Motorola as a unix admin. I was at the plant that built & maintained the hardware and software for the satalites for Iridium. It was interesting to hear engineers talk about the expensive mass of satalites which was at the time (2000) an already outdated network with not enough bandwidth.

    The iridium network has only one location on the planet where communications actually uplinks and downlinks to land communications. Of course they have the ability to communicate to any one of the three or four sites if one were to fail, but it would only use one at any given time.

    So if you made a call in antartica on a iridium sat phone to someone on a land line it would back haul the traffic using line of sight communications leap frogging each satalite before having the uplink/downlink to the ground. So I think it was a total of like 6 hops or something max unless there were of course other issues with the network, it could reroute through any visible satalites.

    So the bandwidth of the entire network is limited to that one uplink/downlink which rotates satalites on an almost hourly basis. So it's not like they could make 1 satalite that could support more bandwidth communication to the ground than the others, they're all built the same. Any iridium sataliate can take the place of any other.

    I know it's way off topic, but interesting to me none the less..

  • Comment removed based on user account deletion

  • The now defunct Breakthrough Propulsion Project (Score:5, Interesting)

    by Pausanias ( 681077 ) <pausaniasx@NOspAm.gmail.com> on Friday February 06, 2004 @11:02PM (#8209273)
    Some of us like solar system exploration just fine, but already have our imaginations fixed on what it would take to get to the other stars. Rocks from Mars may be exciting, but getting to Alpha Centauri would be even more exciting, to say the least.

    NASA used to have a project devoted to seriously studying what it would take to achieve interstellar travel. Unfortunately, funding for it got cut off in 2002. However, they did manage to publish several papers and still have their results online at the BPP site. [nasa.gov]

    Here is a quote from the abstract of one of their papers:
    To travel to our neighboring stars as practically as envisioned by science fiction, breakthroughs in science are required. One of these breakthroughs is to discover a self-contained means of propulsion that requires no propellant. To chart a path toward such a discovery, seven hypothetical space drives are presented to illustrate the specific unsolved challenges and associated research objectives toward this ambition. One research objective is to discover a means to asymmetrically interact with the electromagnetic fluctuations of the vacuum. Another is to develop a physics that describes inertia, gravity, or the properties of spacetime as a function of electromagnetics that leads to using electromagnetic technology for inducing propulsive forces. Another is to determine if negative mass exists or if its properties can be synthesized. An alternative approach that covers the possibility that negative mass might not exist is to develop a formalism of Mach's Principle or reformulate ether concepts to lay a foundation for addressing reaction forces and conservation of momentum with space drives.

  • Ghey (Score:2)

    by TexVex ( 669445 )
    The first quiz is broken. It says I didn't give answers to two questions (3 and 5) when I gave the correct answers. Looks like it was thrown together in a hurry to begin with. Some of the multiple-guess questions use radio buttons and others just use check boxes. Maybe it's cause I'm using a non-IE browser?

  • "Deep"? (Score:3, Insightful)

    by Simon Garlick ( 104721 ) on Saturday February 07, 2004 @12:29AM (#8209700)
    Calling the almost insignificant distance between Earth and Mars "deep space" is like calling ankle-deep water at your local becah "deep ocean".
  • It's too bad that tutorial has been on that site for couple of years. That's probably why the quiz doesn't work. Not to mention that half the links are already dead! :(
  • Is this stuff taught in Evil Medical School anyway, or did NASA just enable a whole bunch of aspiring super-villains to launch their own death star?

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