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Radar reveals two moons orbiting asteroid Florence

astronomynow.com

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Re: Radar reveals two moons orbiting asteroid Florence

#51

Post by DrScump »

SCAQTony wrote: post #12
DrScump wrote: post #11

Earlier quoted context omitted.

The trick is getting it through the atmosphere intact.

The Apollo module was 20,000-kg. We could do it in 50,000-lbs chunks but we would have to process it on the moon first so it wouldn't crater when it landed. If the commodities market tanks, well, we'll value add it by selling it as "all weather platinum or gold siding" at Home Depot. ;-) Apollo weight info: https://www.google.com/search?q=apollo+commad+module+weight&...

Your link says 5,500 kg for the Command module, which is the only part that re-entered.

And of that 5,500kg, maybe 300-400kg was actual payload (astronauts and samples).

Re: Radar reveals two moons orbiting asteroid Florence

#52

Post by labster »

russdill wrote: post #34
labster wrote: post #16

Earlier quoted context omitted.

That much gold would still be worth it for electronic and spaceflight applications. Gold's like a better copper or silver there. And let's not forget the most important application, stereo plug connectors. For platinum or iridium, making it cheaper there would enable all sorts of catalytic chemical processes that are prohibitively expensive now. If abundant enough, new demand will keep the bottom of the market from f…

They actually just plate connectors typically, I think with around 7µm of gold. And no, gold is not a better copper or silver. Both silver and copper are more conductive than gold (then followed by aluminum). Gold is excellent for contact points though as it does not tarnish. Silver conducts heat and electricity the best of the three, but tarnishes the most easily, so it can have issues with high frequency signals as…

The stereo plug thing was a joke, but thanks for educating me on the Calutron. Very cool.

Re: Radar reveals two moons orbiting asteroid Florence

#53

Post by labster »

dnautics wrote: post #23
labster wrote: post #16

Earlier quoted context omitted.

That much gold would still be worth it for electronic and spaceflight applications. Gold's like a better copper or silver there. And let's not forget the most important application, stereo plug connectors. For platinum or iridium, making it cheaper there would enable all sorts of catalytic chemical processes that are prohibitively expensive now. If abundant enough, new demand will keep the bottom of the market from f…

Gold is already not a major expense in electronics. Platinum is currently cheaper than gold. Most pgm catalysts are capable of ~< .1% catalyst loading (e.g. monsanto and cativa processes), and the catalytic metals are easily recovered.

I'd like to believe you about Pt and Ir catalysts, but I just had a chemistry PhD student complaining to me that some paper's processes were too uneconomical because of needing too many platinum atoms in the catalyst. The point was about new processes being viable, not existing techniques.

Re: Radar reveals two moons orbiting asteroid Florence

#54

Post by jaquers »

wiredfool wrote: post #38
jaquers wrote: post #2

Is the 'light' reflecting off the asteroid emitted from the sun? I had never seen or even knew radar could distinguish value like what is shown here. I suppose terrestrial radar looks at much smaller objects and what it sees is emitted from the tower and bounced back in a straight line so that sort of makes sense. More info on the observatory: https://en.wikipedia.org/wiki/Goldstone_Solar_System_Radar

Here's a good explainer on what you're actually seeing in the radar image: http://www.planetary.org/blogs/emily-lakdawalla/2011/3248.ht... * The signal is emitted from a radar installation on the earth, and reflected back to another dish. * Brightness is reflected signal strength. So surfaces that are perpendicular to us will reflect better. The less the surface normal points to us, the less reflection we see. * Up/D…

Thank you very much! Awesome explanation.
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