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Boeing Readies For First Ever Conjoined Satellite Launch

Posted by samzenpus on from the two-by-two dept.

Zothecula writes Boeing has successfully joined two of its 702SP satellites in a stacked configuration in preparation for a launch scheduled for early 2015. Aside from being the first involving conjoined satellites, the launch will also put the first satellites to enter service boasting an all-electric propulsion system into orbit. "Designed by Boeing Network & Space Systems and its defense and security advanced prototyping arm, Phantom Works, the 702SP (small platform) satellites are an evolution of the company's 702 satellite. Operating in the low- to mid-power ranges of 3 to 9 kW, instead of chemical propulsion, the satellites boast an all-electric propulsion system that Boeing says minimizes the mass of the spacecraft and maximizes payload capacity."

67 comments

  1. Sensitive, I like it. by RyuuzakiTetsuya · · Score: 1, Funny

    "Conjoined?" Good.

    TBF, given globalization, part of it, even marginally, was probably actually built in Siam. So it wouldn't be a stretch to call it Siamese...

    --
    Non impediti ratione cogitationus.
    1. Re:Sensitive, I like it. by russotto · · Score: 1

      Not sensitive, just pedantic. The first Siamese satellite launched in December 1993.

  2. So, ion drive or something??? by gstoddart · · Score: 1

    I'll be the first to admit "I'm no rocket scientist", but I'm curious how this works.

    I assume this is a very limited amount of thrust, and can be powered by solar ... but just how much can they do with this?

    Always cool to see they're still doing new stuff, even if I don't know what it means. :-P

    --
    Lost at C:>. Found at C.
    1. Re:So, ion drive or something??? by jehan60188 · · Score: 1

      ion drives, probably
      but those still require ions to work, so there will probably be a tank of hydrogen onboard

    2. Re:So, ion drive or something??? by jehan60188 · · Score: 1

      although, i suppose you could use a PEM fuel cell, and have it eject water vapor

    3. Re:So, ion drive or something??? by gstoddart · · Score: 1

      Why am I picturing Wall-E with a fire extinguisher all of a sudden?

      --
      Lost at C:>. Found at C.
    4. Re:So, ion drive or something??? by ubergeek2009 · · Score: 4, Informative

      According to wikipedia the 702SP uses xenon.

    5. Re:So, ion drive or something??? by asolidvoid · · Score: 1

      IANARS (as is obvious from this question), but If it requires a tank of H, how is this ion engine more efficient than just squirting a small amount of pressurized gas out of the tank instead?

    6. Re:So, ion drive or something??? by tomhath · · Score: 4, Informative

      Yes, ion thrusters. Used to adjust from the original elliptical orbit to the final circular one (and yea, it takes a long time to do that compared to a conventional booster). They've been using these to maintain position for almost 20 years.

    7. Re:So, ion drive or something??? by iggymanz · · Score: 3, Insightful

      Ion engines fire ions at tens of thousands of meters per second, your squirt would have a few meters per second. The momentum change of the ion rocket firing same mass of gas is thus greater by factor of ten thousand or more

    8. Re:So, ion drive or something??? by jehan60188 · · Score: 4, Informative

      good question, the efficiency comes from the speeds achievable
      squirting pressurized gas out of a nozzle into space results in an exit velocity of ve = sqrt(C), where C is some clever arrangement of specific heat, R, T, etc (it's been a while since i've study nozzle design)
      Basically, the exit velocity is limited by mostly the chemical's temperature; quadrupling the absolute temperature would only double the speed, so a lot of energy would be needed

      ions are different (bare with me, I'm not an electrical engineer), because you just need to create them (chemical reaction, heat, etc), and then control them (static field, magnetic field). it's a lot lower power, and a lot greater impulse (over a lot longer time) than what ejecting molecules in to space can provide

    9. Re:So, ion drive or something??? by K.+S.+Kyosuke · · Score: 4, Informative

      And it seems to have a 4.5 kW power input, a specific impulse of 34 kNs/kg (insert an anti-Imperial rant here), and gives a thrust of up to 165 mN, which is fairly decent, Dawn has to do with about a half of that.

      --
      Ezekiel 23:20
    10. Re:So, ion drive or something??? by recharged95 · · Score: 1

      Could be a new ion design considering the originals were developed by Hughes Space back in the 90's.

      1st time: no
      New: maybe.

    11. Re:So, ion drive or something??? by khallow · · Score: 1

      I think the new part is the "conjoined satellite" part. I think one engine places the two satellites, one after the other.

    12. Re:So, ion drive or something??? by K.+S.+Kyosuke · · Score: 1

      Well, more like about a thousand meters per second at room temperature or so? Don't forget that hydrogen has very low molecular weight. But a (comparatively) high-thrust thermal hydrogen thruster would surely interesting for unmanned lunar missions.

      --
      Ezekiel 23:20
    13. Re:So, ion drive or something??? by necro81 · · Score: 4, Insightful

      how is this ion engine more efficient than just squirting a small amount of pressurized gas out of the tank instead

      It has to do with how quickly you can throw the propellant - how much momentum you can impart to it, which in return imparts a certain change in momentum to the rest of the satellite (delta-v). With conventional satellite propulsion, like fuel+oxidizer rockets or monopropellant thrusters, the energy available to impart that momentum is chemically based. That is, the propellants undergo a chemical reaction, get hot and/or change phase into a gas, and nozzles force that gas to exit at some velocity. Details vary with engine and nozzle design, but there are limits on how much thrust you can get each fuel type. Mass in, reaction energy, mass*velocity (momentum) out. Rocket designers measure this "efficiency" with a quantity called specific impulse (measured in units of seconds) For a given mass of fuel, you can pretty quickly calculate what the total delta-v the satellite has available to it.

      Ion engines can impart much higher velocities to the "fuel" than chemical rockets, in part because they are using electrical energy (of which there is an arbitrarily large supply) rather than whatever you can get from chemical reactions. Again, the details vary based on the design, but ion engines tend to have specific impulses much higher than chemical rockets. The actual thrust (i.e., total force) from an ion engine tends to be miniscule, but is provided very efficiently, and can be produced for days or weeks at a time.

    14. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      Fucking all-electric propulsion systems, how do they work?

    15. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      I'm sure you meant to say bear instead of bare, unless you are a nudist.

      As verbs:
      Bare = expose.
      Bear = to accept, endure, or allow.

    16. Re:So, ion drive or something??? by iggymanz · · Score: 1

      They usually use xenon gas, assuming room temp in spacecraft by whatever means that's about 250 m/s.

    17. Re:So, ion drive or something??? by Dunbal · · Score: 2

      Uses far less fuel mass for the same amount of thrust. Like the other poster said, an important component of a rocket engine is not only the amount of mass you can throw out of an engine but also the velocity at which that mass leaves the engine. In fact velocity is far more important (KE = 1/2m v SQUARED). So an ion engine uses tiny, tiny masses at amazingly high speeds. You don't get much kick out of one, but if you're not in a hurry and run it for weeks and months, then you'll get where you need to go eventually. What you do get is a massive savings in fuel, because the mass of fuel you're using per unit time is tiny. Also - GO KERBALS!

      --
      Seven puppies were harmed during the making of this post.
    18. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      They don't, primarily because they aren't "all electric". It's a bullshit marketing term.

      They still consume xenon gas, albeit at much lower quantities than chemical propellant. It's far and away a better system, but it's certainly not the "slap a solar panel on there and forget it forever" solution they imply it is.

    19. Re:So, ion drive or something??? by Dunbal · · Score: 1

      Wait till you see VASIMR...

      --
      Seven puppies were harmed during the making of this post.
    20. Re:So, ion drive or something??? by CrimsonAvenger · · Score: 3, Insightful

      Ion engines [wikipedia.org] can impart much higher velocities to the "fuel" than chemical rockets

      Pedant Mode...ON.

      "Fuel" is what produces the energy. "Reaction Mass" is what you push out the back to make thrust. In chemical rockets, they're the same thing, but in ion engines (or NERVA engines), they're not.

      --

      "I do not agree with what you say, but I will defend to the death your right to say it"
    21. Re:So, ion drive or something??? by sconeu · · Score: 1

      Would removing the propulsion unit from a VASIMR drive be a VASectomy?

      --
      General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
    22. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      Actually Xenon. I forget why the use Xenon but most ion drives use it. I have this hypothesis that with a nuclear (LTFR) reactor, you could use reactor heat to heat water to the point where it not only expands (thermal propulsion) but also disassociates into ions / plasma, use electric/magnetic fields to accelerate them to extreme velocities, then let them recombine (burn) as the final boost. This combines thermal and ion drive, for those times when you need maximum thrust. But IANA rocket scientist, and I'm too lazy to actually work the numbers.

    23. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      I'll just add This from Wikipedia. Electric drive includes other types besides ion thrusters. Also, this is the part that sucks: "ion thrusters carry a fundamental price: the power imparted to the exhaust increases with the square of its velocity while the thrust increases only linearly"

    24. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      ManBearPig = biggest threat to our planet.

    25. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      Xenon actually.

    26. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      a specific impulse of 34 kNs/kg (insert an anti-Imperial rant here)

      You aren't being anti-Imperial. You're being a turd. The standard unit for specific impulse is divided by standard gravity, yielding just seconds, a unit that is common across all unit systems. This is done specifically because it is a common unit across all unit systems, and thus produces absolutely zero possible confusion regardless of your unit system of choice.

      How about you go develop a decimal time standard instead of using those garish base60 seconds.

    27. Re:So, ion drive or something??? by wagnerrp · · Score: 1

      You would need a nuclear reactor to provide enough power to land on the Moon using an arcjet.

    28. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      ManBarePig = biggest threat to our willingness to remain sighted

    29. Re:So, ion drive or something??? by K.+S.+Kyosuke · · Score: 1

      The standard unit for specific impulse is divided by standard gravity.

      Sorry, not where I live. :-p Nobody around here has ever used this unit like this. Why would you include "standard gravity" in it? Is there any "standard gravity" in deep space? That just doesn't make sense, you're just making a silly excuse for a unit that happens to exist only because some countries measure force in pounds. Your argument that "it's common across all unit systems" is hypocritical because that's a wildly implausible reason for why it arose in the first place.

      --
      Ezekiel 23:20
    30. Re:So, ion drive or something??? by Anonymous Coward · · Score: 0

      Why would you include "standard gravity" in it?

      Because non-dimensionalization is an extremely common thing we do in engineering.

    31. Re:So, ion drive or something??? by K.+S.+Kyosuke · · Score: 1

      ...where dimensions can be removed. Unfortunately, force is measured in newtons and mass is measured in kilograms. There's no room for removing units here.

      --
      Ezekiel 23:20
    32. Re:So, ion drive or something??? by K.+S.+Kyosuke · · Score: 1

      Not for landing, for maximizing the mass after TLI if you have a fixed LEO mass budget.

      --
      Ezekiel 23:20
    33. Re:So, ion drive or something??? by K.+S.+Kyosuke · · Score: 1

      Of course they do. I was referring purely to the "squirting H out of a tank" idea since nobody sane would use xenon for that.

      --
      Ezekiel 23:20
  3. First 'conjoined' satellites? by pushing-robot · · Score: 1

    So these don't count?

    --
    How can I believe you when you tell me what I don't want to hear?
    1. Re:First 'conjoined' satellites? by bitingduck · · Score: 2

      Or Herschel & Planck?

      http://orbitalhub.com/?p=475

      They don't stay together, but they're large satellites launched in a stack. The Herschel load doesn't go through the Planck structure, so maybe it doesn't count.

    2. Re:First 'conjoined' satellites? by K.+S.+Kyosuke · · Score: 1

      That was my first thought, too. ;-)

      --
      Ezekiel 23:20
    3. Re:First 'conjoined' satellites? by voidptr · · Score: 3, Informative

      Or GRAIL.

      Or the Orbcomm OG2 constellation that went up in July...

      Launching multiple payloads on a single launch isn't exactly new. It sounds like the innovation here is using the satellites themselves as load structures for each other during launch rather than something like an ESPA ring to save weight and payload volume, but launching more than one satellite per mission is pretty common.

      --
      This .sig for unofficial government use only. Official use subject to $500 fine.
    4. Re:First 'conjoined' satellites? by timeOday · · Score: 2
      Ah, I was wondering, since MIRV ICBMs were developed in the late 1960's.

      Also, bundles of cubesats launched in a P-POD.

    5. Re:First 'conjoined' satellites? by ClickOnThis · · Score: 1

      Nor the Cluster mission?

      The first Cluster launch attempt had four identical conjoined satellites on the first test-flight of Ariane 5. Yes, that one didn't make it to space but four rebuilt satellites were launched two-at-a-time in 2000 from the Baikonur Cosmodrome.

      --
      If it weren't for deadlines, nothing would be late.
  4. Great by PPH · · Score: 1

    Now they can lose two satellites at once when their surplus Russian rocket engine blows up.

    --
    Have gnu, will travel.
    1. Re:Great by ubergeek2009 · · Score: 2

      That was a different company all together. Orbital Sciences had a launch failure shortly after it left the pad. This launch is going to performed by Boeing.

    2. Re:Great by MightyYar · · Score: 1

      Half as many launches means half as many chances to blow up.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    3. Re:Great by MightyYar · · Score: 1

      In addition, this is just the payload package - not the launch vehicle. Apparently this is compatible with the Delta IV, Atlas V, Ariane 5, Proton, and Sea Launch.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
    4. Re:Great by Anonymous Coward · · Score: 0

      How many 777s have had trouble/disappeared lately? :)

    5. Re:Great by Dunbal · · Score: 1

      This is why you buy insurance. Rockets are tricky remember?

      --
      Seven puppies were harmed during the making of this post.
    6. Re:Great by hernick · · Score: 2

      Wrong. These satellites will not be launched by Lockheed-Martin's russian-powered Atlas V rocket, nor by Orbital Sciences soviet-powered Antares.

      These two american-built satellites will launch on the Falcon 9, an all-american rocket, which is powered by 10 american engines.

      Also, if any of the 9 first stage engines were to blow up in a mild fashion that didn't cause too much damage, the Falcon 9 would in fact be able to complete the mission using the remaining engines.

    7. Re:Great by ClickOnThis · · Score: 1

      Half as many launches means half as many chances to blow up.

      And twice the loss if it does.

      --
      If it weren't for deadlines, nothing would be late.
    8. Re:Great by MightyYar · · Score: 1

      That was the original point that PPH made. My counter-point was meant to show that it's not so simple as "oh, no, twice the loss" when there are other variables to consider.

      To be explicit, doubling the payload adds no additional risk if all other things are equal. Assuming a 1 in 10 launch failure, 10 launches of a single payload rocket would give you 9 satellites boosted and 1 destroyed vs 18 boosted and 2 destroyed. The ratio is exactly the same.

      So if the success ratio is the same and you roughly halve your launch costs, it becomes a no-brainer.

      --
      W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
  5. We are Thai if you don't please by tepples · · Score: 2

    TBF, given globalization, part of it, even marginally, was probably actually built in Siam.

    Especially because that's where all the hard drive plants were when it flooded three years ago. Or did they set up shop in different countries after the flood? Either way, obligatory We are Siamese if you please.

  6. I've seen this before by MHz-Man · · Score: 1

    Conjoined satellites with solar panels and two ion engines? I've seen that somewhere before...

    http://img3.wikia.nocookie.net...

  7. East equals out, West equal in, out equals West... by Thud457 · · Score: 1

    Are they using the tether to generate electricity to run the ion engines? Man, that would be wacky to try to drive.

    --

    the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff

  8. That's very nice by Anonymous Coward · · Score: 0

    I like to see cluster bomb technology used for peaceful purposes.

  9. Lots here... by Zoxed · · Score: 2

    Do none of these count as "conjoined" http://en.m.wikipedia.org/wiki...? Does SMART1 not count as electric propulsion? Or is that all too European ;-)

    1. Re:Lots here... by Anonymous Coward · · Score: 1

      conjoined, meaning that the space vehicles htemselvs are connected, instead of using an adapter. SMART1 used chemical propulsion for the transfer burn; this is planned to use only electric propulsion, including the transfer burn. (actually, with it's low total thrust, it's several "burns" for these.

    2. Re:Lots here... by nojayuk · · Score: 2

      The Ariane V has been launching two geosync large satellites simultaneously for quite some time but the upper satellite is carried on a frame/shield called SYLDA that fits around the lower satellite. Usually the two satellites being launched are different sizes and shapes. In this case it appears the Boeing satellites are roughly identical and docked together in their launch fairing saving on the weight and volume of the carrier. However the lower satellite has to cope with the mass of the upper satellite during launch. There is probably a strongback frame of some sort running through the lower satellite to handle that increased load.

    3. Re:Lots here... by Viadd · · Score: 1

      How about two identical Vela satellites stacked together without a frame.

  10. East equals out, West equal in, out equals West... by Anonymous Coward · · Score: 0

    Nice Anathem reference

  11. V.ger by kencurry · · Score: 1

    we are V.ger

    --
    sigs are for losers (except to point out that sigs are for losers)
  12. "First Ever Conjoined Satellite Launch" ? by oneiros27 · · Score: 1

    Um ... so then what was STEREO? (launched in 2006)

    There are pictures of them stacked together

    It was even launched from a Boeing Delta II, so they can't claim it was their first conjoined launch. (which caused major launch delays ... due to the Boeing strike, then the batteries in the second stage being de-certified ... then once the strike was over, the Air Force kept cutting in line for launch pads)

    Disclaimer : I work for the Solar Data Analysis Center. which operates the STEREO Science Center.

    --
    Build it, and they will come^Hplain.
    1. Re:"First Ever Conjoined Satellite Launch" ? by Digicrat · · Score: 2

      Um ... so then what was STEREO? (launched in 2006)

      There are pictures of them stacked together

      It was even launched from a Boeing Delta II, so they can't claim it was their first conjoined launch. (which caused major launch delays ... due to the Boeing strike, then the batteries in the second stage being de-certified ... then once the strike was over, the Air Force kept cutting in line for launch pads)

      Disclaimer : I work for the Solar Data Analysis Center. which operates the STEREO Science Center.

      The same is true for the Van Allen Probes (formerly RBSP): http://en.wikipedia.org/wiki/V...

      Perhaps this is just the first time that Boeing has stacked two satellites?

  13. Unless the explanation is totally wrong ... by Anonymous Coward · · Score: 0

    .... I have no idea how the author can claim that it is "the first"

    Each time a rocket flies, it usually caries MULTIPLE payloads, stacked on top of each other or side by side (depends on the size & rocket configuration). Rarely does a rocket fly just one payload. So the claim that this is the very first stacked mission is just plain ignorance of how satellites are put into space.

    1. Re:Unless the explanation is totally wrong ... by Anonymous Coward · · Score: 0

      Except they're typically not stacked on top of each other, but onto a disposable frame.