From: vince@offshore.ai (Vincent Cate) Newsgroups: sci.space.policy,sci.physics,sci.astro,alt.planets.venus,sci.skeptic Subject: Re: Lunar/Moon Space Elevator, plus another ISS within the CM References: <5d28ff28.0308180816.1340ef3f@posting.google.com> <9f50a7c5.0310220606.2e3b7632@posting.google.com> <9186edb5.0310271958.2e13ea4d@posting.google.com> NNTP-Posting-Host: 209.88.68.230 Message-ID: <9186edb5.0310291349.14bb62b8@posting.google.com> economic_refugee@yahoo.com (E.R.) wrote in message news:... > The Space Elevator Final report to NIAC > [...] > Chapter 4 - Power Beaming > http://www.isr.us/Downloads/niac_pdf/chapter4.html These guys are talking "54 watt/cm2 power densities". This is 540,000 watts/meter^2. This is a reentry heating type number. I think the solar cells would ablate in a few seconds. :-) So I think there is a mistake someplace. They say they got this from a reference: D'Amato, F.X., Berak, J.M., and Shuskus, A.J.. 1992. Fabrication and Test of an Efficient Photovoltaic Cell for Laser Optical Power Transmission. IEEEPhotonics Technology Letters 4, No. 3: 258. I don't have this reference and so can not check, but I strongly suspect it is really supposed to be 0.54 watts/cm^2. This would be better than 10 times regular sun powered solar cells. -- Vince