Speaking of lead balloons, Lowell Wood once computed that you could harvest a metallic asteroid by slicing it into 20 triangular slabs, welding it into an icosahedral vacuum balloon, easing it into atmospheric reentry, and bringing it to rest floating above the ground. Without internal pressurization with Moravec's niobium cannon balls. --rwg On Fri, Aug 24, 2018 at 4:21 PM Bill Gosper <billgosper@gmail.com> wrote:
(Re-sent due to xmission.com braindamage.)---------- Forwarded message --------- From: Bill Gosper <billgosper@gmail.com> Date: Sat, Aug 18, 2018 at 9:36 AM Subject: a huge boon to the dirigible industry To: Wolfram Technical Support <support@wolfram.com>
In[31]:= ChemicalData["Nitrogen", "MolecularMass"]
Out[31]= Quantity[28.014, "AtomicMassUnit"]
(A mole of nitrogen gas weighs ~one ounce.)
In[32]:= ChemicalData["Air", "MolecularMass"]
Out[32]= Quantity[794.9, "AtomicMassUnit"]
Takes my breath away. --Bill