Really excited about Jaxa's work off late, they seem to be very forward thinking. Just out of interest, is anyone aware of how much power is expected from the sail?

Quote from: Robson68 on 05/02/2010 01:39 pmReally excited about Jaxa's work off late, they seem to be very forward thinking. Just out of interest, is anyone aware of how much power is expected from the sail? If you have a reasonable math skills then try this equation to help yourself get the answer: a = 2Isr/ma = acceleration I = solar radiation intensity (watts/meter squared) i.e. 1400 W/m^2s = surface area of sailr = reflection efficiency m = mass

Quote from: DiggyCoxwell on 05/04/2010 06:15 pmQuote from: Robson68 on 05/02/2010 01:39 pmReally excited about Jaxa's work off late, they seem to be very forward thinking. Just out of interest, is anyone aware of how much power is expected from the sail? If you have a reasonable math skills then try this equation to help yourself get the answer: a = 2Isr/cma = acceleration I = solar radiation intensity (watts/meter squared) i.e. 1400 W/m^2s = surface area of sailr = reflection efficiency m = massc = speed of lightI believe he's talking about electrical power. The sail is going to only be partially covered in solar panels (just a tiny fraction of the total sail's area), it's going to be closer to the Sun than the Earth is (if it's near Venus, that means the 1370W/m^2 is doubled), and will use thin-film solar cells, which are usually only 10% efficient at best. It will be hard to guess how much power is to be expected, since the insolation is unknown, the surface area of the solar arrays is unknown, and the efficiency of the cells is unknown. Unknown to us, that is. We can make educated guesses at these quantities, but that's about it, unless someone fills us in.

Quote from: Robson68 on 05/02/2010 01:39 pmReally excited about Jaxa's work off late, they seem to be very forward thinking. Just out of interest, is anyone aware of how much power is expected from the sail? If you have a reasonable math skills then try this equation to help yourself get the answer: a = 2Isr/cma = acceleration I = solar radiation intensity (watts/meter squared) i.e. 1400 W/m^2s = surface area of sailr = reflection efficiency m = massc = speed of light

Actually, I think only 3 of the 6 spacecraft (Akatsuki, IKAROS and UNITEC-1) will be on an interplanetary trajectory. The 3 minisats (Negai, WASEDA and KSAT) will be released before Akatsuki separates from the upper stage

How long after launch until Ikaros is deployed?