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Anyone know if this would be capable of carrying a weapon that could hit targets on earth? I assume all you'd need is a smart aerodynamic projectile and gravit

• csmithuk 13y ago
  Yes it is capable. There's a 2.1m x 1.2m payload bay[1]. Various nefarious things that go boom on a large scale will fit in that hole. [1] http://en.wikipedia.org/wiki/Boeing_X-37#X-37B_2 http://en.wikipedia.org/wiki/Boeing_X-37#X-37B_2
  • deletes 13y ago
    Projectiles have to survive atmospheric reentry. Wiki says that modern icbms have a reentry speed of 4km/s, vs 28km/s for x-37.
    • csmithuk 13y ago
      Who said the X-37 has to survive though? That can do a 180 and decelerate using the main AR2-3 at the cost of a decaying orbit then drop the payload at 4km/s.
      • deletes 13y ago
        I'm not an expert but I will state that x-37 in orbit doesn't have 23km/s delta-v. I think wiki for similar vehicles can confirm that: http://en.wikipedia.org/wiki/Delta-v_budget http://en.wikipedia.org/wiki/Delta-v_budget
        • csmithuk 13y ago
          Don't forget aerobraking which can knock a big chunk off that delta-v.
        • VLM 13y ago
          Its a hydrazine monopropellent, or so they say, so an Isp of 250 or so would be impressive. Someone with a lot more time on their hands can tell you the mass fraction required to get 23 KM/s outta a 250 second Isp and its going to have about as many 9's as reliability marketing material. So yeah, thats not happening.
      • VLM 13y ago
        That would be about Mach 10 weapon launch. I don't think that's been seriously studied or tried in practice. That would be quite a technological achievement all by itself, aside from everything else the thing can do. Of course the vehicle is going to be destroyed anyway, so just carry the payload all the way down till it goes boom or whatever, unless you were hoping to launch multiple warheads. The problem is the whole vehicle is very light, so you're not going to fit a B-52 worth of payloads in a vehicle who's launch weight is, I believe, lighter than a GBU-43. My point being that if vehicle plus payload at launch is lighter than a GBU-43, there's not much point in being concerned with how many GBU-43 it can be dropped if it can only carry a fraction of one anyway. The main problem is its hard to think up a mission profile where a cruise missile wouldn't be cheaper and more effective.
    • JulianMorrison 13y ago
      X-37 is an ICBM (with a guided glide mode). Airplane go boom.
      • deletes 13y ago
        Didn't think of that. In that case a specialized icbm would be better. As space-x shows you don't need wings to be accurate from orbit. Nasa should really drop this winged approach. They can't because they have experience and scientists on that field, and change is hard.
        • mcguire 13y ago
          NASA has. The shuttle program is deceased. This isn't NASA's. http://www.nasa.gov/exploration/systems/index.html#.UvE53R_Evv4 http://www.nasa.gov/exploration/systems/index.html#.UvE53R_E...
    • chiph 13y ago
      Doesn't have to be an ICBM or some type of rocket - a kinetic energy weapon (giant lawn darts from space) could be effective, but without nasty radioactivity afterwards.
      • backprojection 13y ago
        Are there materials dense enough to be useful for this, and thermally non-conductive/stable enough to withstand the heat of reentry?
        • nicholassmith 13y ago
          If I remember rightly (it's been a while since I read up on them), they proposed using tungsten rods initially. Not sure if they'd still go down that route, or whether they'd use something a bit more exotic (carbon nanotubes is always the go to answer for exotic-scifi style things).
        • sp332 13y ago
          Tungsten carbide and uranium cement have been postulated. https://en.wikipedia.org/wiki/Space_weapon#Orbital_bombardment https://en.wikipedia.org/wiki/Space_weapon#Orbital_bombardme... Interestingly, these are not prohibited by any treaties. The US Air Force estimated a 1-foot (.3 meter) diameter tungsten pole would impact ~Mach 10. It would weight 9 tons and have the same destructive force as 7.5 tons of dynamite, but it would only take 15 minutes to get anywhere in the world and there would be no ICBM launch warning. https://en.wikipedia.org/wiki/Kinetic_bombardment#Project_Thor https://en.wikipedia.org/wiki/Kinetic_bombardment#Project_Th...
          • deleted 13y ago
            [deleted]
    • Gravityloss 13y ago
      28 km/s? It would be more than escape velocity (11.2 km/s), where did you get that? Low earth orbit is around 8 km/s. Still not totally the same as and ICBM, but could be done. But why would you stuff the rods in an X-37B? You could just launch a light satellite without all this re-entry stuff and you'd get many more rods for the same mass... or then you could use a smaller launcher. The X-37B is basically a reusable payload fairing, a very heavy one at that. Oh well, it isn't even that because the rocket requires another outer expendable payload fairing.
      • deletes 13y ago
        I was completely wrong on the velocity, mixed the types and didn't even think about the weird number. I should rely on wiki less.
• naz 13y ago
  You'd also need some retrograde thrust on the payload, and for your orbit to be inclined over the target.
• arethuza 13y ago
  The Soviets had a system that was based on putting warheads into a fractional orbit, rather than on a ballistic path - Fractional Orbital Bombardment System (FOBS). http://en.wikipedia.org/wiki/Fractional_Orbital_Bombardment_System http://en.wikipedia.org/wiki/Fractional_Orbital_Bombardment_... I can't find any details, but most descriptions seem to imply that they needed to have a rocket engine on the warhead to come out of orbit (which is what I would expect).
  • drakeandrews 13y ago
    Correction: FOBS put warheads in low earth polar orbit.
    • arethuza 13y ago
      Out of interest - what part of what I said are you correcting? :-)
• ckozlowski 13y ago
  Think beyond hitting targets on earth, and even in orbit. Something like the X-37 allows the Air Force to go up and capture another satellite, perform modifications to it, or even bring it back down to Earth for analysis. No need to blast enemy satellites out of orbit, just rocket up and snatch it.
• aaronem 13y ago
  Yes, but: nuclear weapons in space are prohibited by at least two treaties to which the US is a signatory; any point on the globe worth hitting with conventional weapons would be far easier and cheaper to hit with, say, a cruise missile or a drone-launched Hellfire; last but not least, you'd first have to build a weapon to fit in this thing's cargo bay, which almost certainly has not been done because, given the first two mentioned points, it's not worth anyone's time or money to bother. To understand the X-37, you need a reasonable knowledge of the origins of the Space Shuttle program. The only reason that program came to even the bastardized fruition it did was because the Air Force signed on, and they did so only because they needed a means of servicing and maintaining their orbital equipment. In theory, and occasionally in practice, this means involved actual human astronauts going up and doing spanner work on satellites in orbit, but this was expensive and fraught with undue difficulty; cheaper and easier was simply to stuff the whole satellite into the Shuttle's payload bay and haul it back down the gravity well for repair, refit, and relaunch, and indeed many Space Shuttle missions involved precisely this evolution. (It's probable, if uncertain due to the Air Force's bent for secrecy with regard to their payloads, that the Shuttle was used to return some or most of these satellites to orbit; on the other hand, a Titan-IV's probably cheaper, and the Air Force has used plenty of those, too. I don't know much about what goes into that sort of decision.) The X-37, then, far from being some kind of conspiracy-theory FOBS, is just a Space-Shuttle-style "space truck". The major difference is that technology has now reached a point where it's possible for such a vehicle to satisfy the Air Force's mission parameters without having to involve all the complex, costly, and potentially disastrous encumbrances required to carry living humans into space. Edit! I've finally just recalled the name of the book from which I gained my understanding of the politicking which took the Space Shuttle program from initial conception to final operational "Space Transportation System". That book is The Space Shuttle Decision, published by NASA as part of the NASA History Series, and you can read it online at http://www.nss.org/resources/library/shuttledecision/ http://www.nss.org/resources/library/shuttledecision/ and, oh, probably lots of other places as well. A bit dry, but marvelously detailed and surprisingly objective given its origins; I recommend it unreservedly to anyone with an interest in the history of its subject matter.
  • jrockway 13y ago
    I love your phrasing in this comment, specifically "stuff the whole satellite into the Shuttle's payload bay and haul it back down the gravity well".
• sdfjkl 13y ago
  Yes. Read about Project Thor: http://en.wikipedia.org/wiki/Kinetic_bombardment#Project_Thor http://en.wikipedia.org/wiki/Kinetic_bombardment#Project_Tho... A payload of slightly smaller than described tungsten rods would fit on a craft of this size, and according to the article this type of weapon is not prohibited by any current treaty. It could hit anywhere with practically no warning and no need to enter airspace. It's almost impossible to defend against. Scary shit.
• InclinedPlane 13y ago
  Orbital based weapons aren't really an advantage, as it turns out. A weapon in orbit has to wait until it's over the target before it can attack, which could be a long wait. It also has all of the problems of putting anything in orbit, maintenance, station keeping, longevity, etc. In contrast, a weapon designed to fly through space on a ballistic trajectory can be much simpler and cheaper. Moreover, because they start on the Earth ICBMs can always hit their targets within a single sub-orbital hop, they don't have to wait for attack windows to line up.
• ihsw 13y ago
  The concept isn't new -- it's called kinetic bombardment[1]. Generally speaking, the amount of damage for a tungsten rod the size of a telephone pole would match low-yield atomic detonations. [1] http://en.wikipedia.org/wiki/Kinetic_bombardment http://en.wikipedia.org/wiki/Kinetic_bombardment
  • peeters 13y ago
    Interesting concept, but I wonder about the economics. A telephone pole has a volume of about 3 million cubic centimetres. Tungsten's density is ~20 g/cm^3, so we're talking about 60 000 kilograms of tungsten. At around $40/kg, that's ~2.5 million dollars per rod just in raw materials. But that's ignoring the cost of bringing a 60 metric ton rod into orbit, of course. You'd need a Falcon Heavy launch per rod, ignoring the problematic dimensions (let's assume you can cold weld a few pieces together in space). That's at least another $60 million per rod for the launch costs.
    • jimktrains2 13y ago
      Just toss some "small" asteroids down then. (More an issue once we get to the point of interplanetary war, but still cheaper than manufacturing pure tungsten rods).
    • morsch 13y ago
      60t of lead, on the other hand, will go for a mere 120k USD, at about double the volume. Not sure if the effect will be the same (it certainly sounds like a good way to poison vast swathes of land).
• a8da6b0c91d 13y ago
  Some people say the "rods from god" idea is really deployed on satellites. The USAF could make tungsten metal spears fall out of space and hit precise targets with the force of a small nuclear blast.