From: Henry Baker <hbaker1@pipeline.com> https://www.youtube.com/watch?t=2&v=BIy5g4bvskM This is a visualization of the trajectory designed by the ACT-ISAS team that won 1st place in the GTOC8. The theme chosen by NASA / JPL for the 8th edition of the GTOC was “high-resolution mapping of radio sources in the universe using space-based Very-Long-Baseline Interferometry (VLBI)”. Three spacecraft had to depart from the Earth and needed to perform several interferometric measurements of one of 420 radio sources. An interferometric measurement could be made when the three spacecraft lay on a plane whose normal pointed towards the radio source. Moon gravity assists and low-thrust propulsion had to be used to target each interferometric measurement.
--I don't understand. OK, first of all, if a bunch of radio telescopes receive a signal (and let me assume they each record the signal along with ultra-accurate record of the time), then cannot they do "interferometry" algorithmically later REGARDLESS of whether they lie in a plane normal to the line to the source, they can do it in pretty much any geometry at all. No? And there is no need for the telescopes to be in real time communication with each other, which in any event would be rather problematic if they were a million miles apart, under that assumption. [The best atomic clocks have accuracies of order 1 part in 10^17 or 10^18 now, which seems fully adequate for all this.] So, either I'm confused, or NASA is.
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