Space Shuttle to the Moon

Discussion in 'Astronomy, Exobiology, & Cosmology' started by thecollage, Nov 21, 2007.

  1. thecollage Registered Senior Member

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    How would a space shuttle land on the moon? It would need a runway right?
     
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  3. snake river rufus Registered Senior Member

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    The shuttle was designed for low earth orbit only. It was never intended to go to the moon.
     
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  5. snake river rufus Registered Senior Member

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  7. phlogistician Banned Banned

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    Q. How does a space shuttle land?
    A. Like an aeroplane, using wings for lift, control surfaces for direction, and swerving manouvers to lose speed via reaction with the atmosphere. Oh bugger, atmosphere!

    Q. How do we get an atmosphere around the Moon?
    A. er, well, umm, er, ah well how about lots of hot air from pseudoscientists?
     
  8. snake river rufus Registered Senior Member

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    Or hoax believers! Send bart siebrel and let him rant to my hearts content.
     
  9. Vega Banned Banned

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    The shuttle would use the same principle as the older lunar modules!
     
  10. Nasor Valued Senior Member

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    The shuttle itself couldn’t land on the moon, but it could carry some sort of lunar lander in its cargo bay that the astronauts could use to land on the moon’s surface and then return to the shuttle. The space shuttle's cargo bay is almost large enough to carry 3 of the Apollo lunar laders (the shuttle's cargo bay is 60x15 feet, while an Apollo LEM was only 21x14 feet. The shuttle would have to remain in orbit around the moon.

    The only problem is that the shuttle doesn’t have enough fuel to make it to the moon, so it would have to refuel in orbit (presumably with fuel that was launched on a separate, unmanned rocket).

    The shuttle can get a few thousand kg of cargo to geosynchronous transfer orbit, which requires about 12.2 km/sec of delta-v. Going from there to a low lunar orbit and back would only take about anouther 2.1 km/sec of delta-v; so interestingly, it looks like the shuttle is only about 20% short of the fuel it would need to get to the moon.

    The shuttle can't land on its tail.
     
    Last edited: Dec 2, 2007
  11. orcot Valued Senior Member

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    I doubt the space shuttle ever reaches GEO altough I would have to look it up. My best gues is that it only reaches low earth orbit (the height of the ISS) and then launches something with a little ion engine. For what I care they chould place a couple of shuttles in the museum and send one up stript of it's heath shield and wings and instal a nuclair reactor (subclass or something) in it creating the option of a VASIMR engine so future probes should only get to low earth orbit refuel use the much more efficient VASIMR to near escape earths gravity well and then set of for further. Then again it might be more simple to yust retire them
     
  12. superluminal I am MalcomR Valued Senior Member

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    The shuttle can not and does NOT reach GSO. GSO satellites may be deployed from the shuttle cargo bay and have their own boosters to get them into GSO.
     
  13. Nasor Valued Senior Member

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    The shuttle can get to GTO with a few tons of cargo, but can't get to GSO. Although actually the delta-v requirements for going from LEO to GSO are almost exactly the same as going from LEO to a low lunar orbit. The shuttle is about 20% short on fuel for either one.

    Edit: 20% short on delta-v, anyway...I'm not sure how the math would work out for how much actual fuel it would need. Probably a lot less than 20% of its initial launch fuel.
     
  14. superluminal I am MalcomR Valued Senior Member

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    Just a note: The shuttle uses a combination of thrusters and control surfaces on reentry, transitioning from purely thruster-based maneuvering at the beginning to purely cotrol surface maneuvering when the atmosphere becomes dense enough.

    Otherwise, you're right. Shuttles to the moon is not what they were designed for or are remotely capable of.
     
  15. superluminal I am MalcomR Valued Senior Member

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    Err... really? I've never known of a shuttle being placed into a geostationary transfer orbit. Any references for this?
     
  16. Nasor Valued Senior Member

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    According to wikipedia the shuttle can get a few thousand kg of cargo to GTO, but I agree that I don’t think it can go to GSO.

    I did the math, and it looks like it would take about 75 metric tons of fuel (about 3 space shuttle or Delta 4 rocket loads worth of mass) to get the orbiter + 30 tons of LEM from GTO to a low lunar orbit and back to earth. So assuming you can work out some way to refuel the shuttle in orbit, it looks like you need three launches to haul up enough fuel to get the orbiter+LEM to the moon and back.

    Not really a very good deal…
     
  17. superluminal I am MalcomR Valued Senior Member

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    Hi Nasor.

    I just did some checking too and every reference I can find talks about the shuttle deploying the cargo, and the cargo boosting itself into GTO or GEO.

    I'm pretty certain that the shuttle itself has no ability to go into either of these more energetic orbits. Right?
     
  18. Nasor Valued Senior Member

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    Wikipedia says it has a payload capacity of 3800 kg to GTO. I don't know if that's accurate, or if anyone has ever done it.
     
  19. superluminal I am MalcomR Valued Senior Member

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    I think what that means is that the combined weight of the payload and fuel (needed to get it into a GTO) is 3800kg. In other words, given the ISP of the booster, the shuttle can deploy a payload with a maximum combined mass of 3800kg, that could boost itself into a Hohmann transfer orbit.
     
  20. D H Some other guy Valued Senior Member

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    You can't just that. While the delta-v to get something from LEO to GEO obviously doesn't depend on the mass of that something, the amount of fuel needed most certainly does depend on the mass. The delta-V to get a little satellite to GEO pertains to the satellite. It does not pertain to the Shuttle.

    A back of the envelope calculation here. The Shuttle can bring 24,400 kilograms of payload to low earth orbit. Make 95% of that mass fuel -- the same monomethylhydrazine and nitrogen tetroxide fuel with a specific impulse of 313 seconds used by the OMS. (That 95% is very generous. That includes tanks and extra plumbing to route the fuel to the OMS.) The Orbiter itself has a dry mass of 104,000 kilograms. What kind of delta-V would that buy?

    That 313 second specific impulse corresponds to an effective exhaust velocity of 3.07 kilometers/second. Applying the rocket equation \(\Delta v = v_e \ln\left(m_0/m_1)\) with \( v_e=313\mathrm{s}*9.80665 \mathrm{m}/\mathrm{s}^2\), \(m_0=104000+24400=128400 \mathrm{kg}\), \(m_1=104000+24400*0.05=105220\mathrm{kg}\) yields a delta-V of 611 meters/second. That's not even close to the 4 kilometers/second needed to get from LEO to GEO.
     
  21. D H Some other guy Valued Senior Member

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    The Shuttle gets a few thousand kilos of cargo to GEO by carrying that few thousand kilos plus an Inertial Upper Stage as cargo to LEO. The IUS+cargo are released from the Shuttle in LEO. The IUS, not the Shuttle, is what gets the cargo from LEO to GEO. The Shuttle does not go along for the ride. The Shuttle has a paltry 100 m/s or so of delta-V itself on-orbit -- just enough to perform a deorbit burn.
     
  22. superluminal I am MalcomR Valued Senior Member

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    There ya go.
     
  23. Nasor Valued Senior Member

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    Thanks for the clarification on the shuttle goingto to GSO/GTO. I redid the calculations for the shuttle getting to low lunar orbit and back from LEO (instead of GSO), and it came out to 200 tons of fuel assuming you get to use the 440 sec. main engines.
     

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