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"{{w|CubeSat}}-based design" refers to a type of miniaturized satellites that is made up of 10-centimeter cube units (here seemingly consisting of 3 units) and enables cost-effective means for getting a payload into orbit.
 
"{{w|CubeSat}}-based design" refers to a type of miniaturized satellites that is made up of 10-centimeter cube units (here seemingly consisting of 3 units) and enables cost-effective means for getting a payload into orbit.
  
The title-text refers to {{w|Russell's paradox}}, also formulated by Bertrand Russell. Russell's paradox was a flaw found in  {{w|naïve set theory}} where one could consider "the set of all sets that do not contain themselves" (a "set" is a mathematical term for a "group of things" -- "things" in this case including a set itself). The paradox arises with whether this set, in turn, contains itself: if it does, then it cannot; if it doesn't, then it must. Similarly, like in the {{w|barber paradox}}, the vehicle which launches only vehicles which do not launch themselves is impossible: if the vehicle takes off, it must launch itself as well as the teapot, and thus can never be launched (without violating alleged NASA regulations, at least). That said, he might get around those regulations by using an initial first stage with an offboard power source for the moment of launch, for example a laser striking a parabolic mirror and massively heating air beneath the craft, causing expansion, or a compressed gas cold launch system such as used to clear submarine launched missiles from their tubes before the real rocket motor ignites.
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The title-text refers to {{w|Russell's paradox}}, also formulated by Bertrand Russell. Russell's paradox was a flaw found in  {{w|naïve set theory}} where one could consider "the set of all sets that do not contain themselves" (a "set" is a mathematical term for a "group of things" -- "things" in this case including a set itself). The paradox arises with whether this set, in turn, contains itself: if it does, then it cannot; if it doesn't, then it must. Similarly, like in the {{w|barber paradox}}, the vehicle which launches only vehicles which do not launch themselves is impossible: if the vehicle takes off, it must launch itself as well as the teapot, and thus can never be launched (without violating alleged NASA regulations, at least).
  
 
The barber paradox can be stated as follows: "Consider a town in which a man, the barber, shaves precisely those men who do not shave themselves. Does the barber shave himself?" Either answer, yes or no, leads to a contradiction. Sometimes the paradox is incorrectly stated, replacing "precisely those" with "only". Under that scenario, there is no paradox; the barber is merely unkempt.
 
The barber paradox can be stated as follows: "Consider a town in which a man, the barber, shaves precisely those men who do not shave themselves. Does the barber shave himself?" Either answer, yes or no, leads to a contradiction. Sometimes the paradox is incorrectly stated, replacing "precisely those" with "only". Under that scenario, there is no paradox; the barber is merely unkempt.

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