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| . 1.5 GW from a 0.25 km² antenna is 6 kW/m² at the WAG transmitter, tens of kW/m² in the upper atmosphere below the vehicle. Power levels less than 1 kW/m² can cause thermal blooming and defocusing of the beam. | . 1.5 GW from a 0.25 km² antenna is 6 kW/m² at the WAG transmitter, tens of kW/m² in the upper atmosphere below the vehicle. Power levels less than 1 kW/m² can cause thermal blooming in air, and defocusing of the beam. |
Explore / Create
My Life in Pursuit of New Frontiers, Hidden Worlds. and the Creative Spark
Richard Garriott with David Fisher, Central Biography 794.8 GARRIOTT 2017
Richard Garriott created video games, earning enough to be a tourist. Son of astronaut Owen Garriott.
- p270 Peter Diamandis, Byron Lichtenberg, and Ray Cronise start Zero Gravity Corporation in 1994, 727 in parabolic flight to 32 kft.
p279 Wife Laetitia is granddaughter of André de Cayeux de Senarpont, for whom Cailleux crater on the lunar farside is named.
Briefly president and COO of Escape Dynamics attempting microwave-powered launch.
- WTF? A 6 gee (WAG) trajectory to LEO (8 km/s) requires a 500 km acceleration path, perhaps 80 km up. Even with multiple transmitters, that is a lot of 120 km (WAG) beam paths; assuming 25 GHz, 12 mm wavelength, focusing on a collector "the size of a minivan" (3 meters) requires a 500 meter scale phased array. Assuming a 5 tonne vehicle (including propellant), thrust is 300 kN. Assuming an exhaust velocity of 10 km/s, that is 30 kg/s of helium (which does not grow on trees) with a power level of 1.5 GW. Yikes!
WAG payload fraction < 0.4
- 1.5 GW from a 0.25 km² antenna is 6 kW/m² at the WAG transmitter, tens of kW/m² in the upper atmosphere below the vehicle. Power levels less than 1 kW/m² can cause thermal blooming in air, and defocusing of the beam.