I don't get it?
*) Satellites, even CubeSats, need to be above a certain volume, to ensure the electronics stays at a reasonably constant temperature. The temperature of a thin FlimsySat would very quickly plummet to that of liquid Nitrogen when in the shade of the Earth or the Moon, and toast at around 150 degrees C when exposed to the Sun. What COTS components do they expect will survive this temperature cycle?
*) Space junk is a serious concern with the relevant authorities due to the potential problem of the
Kessler syndrome. CubeSats are intentionally launched (kicked off by a spring) at fairly low altitudes. This way their orbit will naturally degrade fairly quickly, after which they re-enters the atmosphere and burns up. The Moon has no atmosphere, so an object, which doesn't hit the surface on the first orbit, will effectively stay in orbit forever. I cannot see this group getting permission to launch thosands on FlimsySats in low Moon orbit. That would be insane.
*) S-band is about 3 GHz, while X is around 10 GHz. A parabolic dish reflector needs to have a surface, where deviations are within a quarter wavelength, for it to have a gain close to the theoretical value, given by its diameter. At 3 GHz a quarter wavelength is about 2.5 cm. Building a fully steerable dish for 3 GHz of 5 meter in diameter is hard to do in your back yard. Sure, amateurs do sometimes have dishes of that size, but they are usually only used up to 1.3 GHz for this very reason, if even that. At higher frequencies hams tend to use smaller, off the shelf units.
*) A fully steerable, commercial dish of 5+ m diameter, useable at 3 GHz or above, is very expensive. Very few will be in the hands of individuals, and the commercial/science antennas are all booked solid with 'paying' work, just to keep up with the growing needs of just the regular, scientific community.
*) These people will no get access to facilities like the DSN for something like this, that is just plain delusional. The DSN cannot even keep up with the work NASA throws at it.
*) Cameras are of very little use, unless your spacecraft at the very least has spin stabilization. A FlimsySat would just be randomly tumbling through space.
*) Same issue with solar cells and the communication link to Earth, unless you have batteries (or super capacitors) on board. Without either the FlimsySat would reset every time an edge is pointing in the general direction of the Sun. Which will be very frequently for a small, disc shaped object in hard vacuum, not equipped with any guidance systems.
*) A solar sail requires very accurate guidance plus a stable orientation of the spacecraft in order to do anything at all. Tumbling spacecraft plus solar sail equals fail. Might work for the CubeSat carrier trip to the Moon, but steering the individual FlimsySats would be impossible after launch from the carrier.
*) The free space path loss between the Moon and the Earth is more than 200 dB at 3 GHz. What kind of receivers do they expect people to have, if the TX power from a FlimsySat is, say, 10 mW (+10dBm)? What kind of downlink bandwidth is shared by the 50 people on a single FlimsySat?
*) Nobody outside the commercial/education/military sector will get permission to operate the thousands of Earth bound S- and X-band
transmitters required to establish an uplink, assuming people were willing to pay for those in the first place.
Could probably go on for a while, but think I'd better stop here...
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