I have been thinking about satellites and I come to two main objections:
1) Instability. The fact that we do not observe other natural satellites except Moon implies that all other orbits in this system maybe unstable—not sure, but why we can’t see even a smallest boulder?
2) Cost. The rate of natural erosion in around 1 mm in 1 mln years, or 1 meter in 1 billion years, not counting for larger collisions. This implies that the size of the satellite should be at least a 4 meters in diameter, and assuming that it is made from lead, it will weight 350 tons. Putting a ton on GEO costs now at least 10 mln USD, so only launch will cost 3.5 billions dollar, and as launch is typically only a fraction of cost of the payload, the whole project will cost more than 10 billion USD. For such price there many more useful things could be done. For example, opportunistic payloads on planned landers at Moon cold craters will cost only a fraction of this cost.
I also sceptical for any long-term working machinery before full blown molecular manufacturing, which could be used as eternal nest of ants for the messaging.
Where did you get your numbers? Falcon Heavy brings up 26 tons to GEO for 90 million (by the price on the website without additional deals).
Also given the time-spans that are involved it would make sense to wait for BFR to bring down the prices. It also would be a good payload for a maiden mission.
I used earlier prices for Falcon, not prices of the larger ones. The longer we could wait, the cheaper would be such mission, but the chance that some existential catastrope will happen before it is growing.
I have been thinking about satellites and I come to two main objections:
1) Instability. The fact that we do not observe other natural satellites except Moon implies that all other orbits in this system maybe unstable—not sure, but why we can’t see even a smallest boulder?
2) Cost. The rate of natural erosion in around 1 mm in 1 mln years, or 1 meter in 1 billion years, not counting for larger collisions. This implies that the size of the satellite should be at least a 4 meters in diameter, and assuming that it is made from lead, it will weight 350 tons. Putting a ton on GEO costs now at least 10 mln USD, so only launch will cost 3.5 billions dollar, and as launch is typically only a fraction of cost of the payload, the whole project will cost more than 10 billion USD. For such price there many more useful things could be done. For example, opportunistic payloads on planned landers at Moon cold craters will cost only a fraction of this cost.
I also sceptical for any long-term working machinery before full blown molecular manufacturing, which could be used as eternal nest of ants for the messaging.
Where did you get your numbers? Falcon Heavy brings up 26 tons to GEO for 90 million (by the price on the website without additional deals).
Also given the time-spans that are involved it would make sense to wait for BFR to bring down the prices. It also would be a good payload for a maiden mission.
I used earlier prices for Falcon, not prices of the larger ones. The longer we could wait, the cheaper would be such mission, but the chance that some existential catastrope will happen before it is growing.