<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:14pt"><div><span>Tom Nowell wrote:</span></div><div><span></span> <br>"One method mentioned was constructing a large plastic film </div><div>in a sphere around your asteroid, <span id="misspell-0"><span id="misspell-0" class="mark">metallising</span></span> half of it to form </div><div>a reflector which then heats up the asteroid. The most volatile </div><div>parts vaporise and form a shell on the inside of the film. You </div><div>cut this apart, then repeat the process for higher and higher </div><div>temperatures, each time getting a different set of </div><div>temperature-controlled vapor, until you are left with highly </div><div>refractory stuff in the <span id="misspell-1"><span id="misspell-1" class="mark">centre</span></span>."</div><div> </div><div>Each cycle would leave a certain amount of vapor in the
space</div><div>between the asteroid and the film which would be lost when</div><div>you cut away the film. This would be a larger amount for</div><div>vapor created at low temperatures and less when at high</div><div>temperatures.</div><div> </div><div>The idea is generally sound and resembles distillation of</div><div>hydrocarbons into different fractions but I would favor the</div><div>container <span id="misspell-2">remaining</span> intact the whole time and removing the</div><div>fractions as they are generated instead of starting and</div><div>stopping the process.</div><div> </div><div>Dennis May<br></div></div></body></html>