ELT pretty much would require space manufacturing base - for the mass involved, you could probably furnish a small moon town.
The problem is that the ones making the mess aren't going to pay for that, and I shudder at the costs involved in just space assembly of something the size of ELT...
Edit to the slow reply ;) - the 400 tons is just the estimate zerodur mirror segments for the main mirror, nothing of the support structures... and didn't include ~65 tons of spare segments (ELT plans to replace two daily or something like that).
Starship will be an incredible game changer for space economics. Look at this progression:
- $50,000/kilogram for 27,500kg of payload (Space Shuttle, 1981-2011)
- $2,500/kg for 22,800kg of payload (SpaceX Falcon 9, 2010-present)
- $20/kg* for 100,000kg of payload (SpaceX Starship, 2022??)
*: This is the estimated operational cost, not the price of a launch
For a ballpark launch cost estimate, assuming that the mirror segments would be mass constrained rather than volume, it would cost $8M (plus however far off the cost estimates are, plus profit) just to get the mass into space. Maybe say $20M just to pad it a bit? There would almost certainly need to be more money spent on designing the whole thing to work in space, of course. But these projects have long planning horizons, there's no way anyone would have considered building something large in space before Starship was announced (other than nation-state level prestige projects).
I suspect we'll see a flood of small to medium sized projects announced once Starship completes its first commercial LEO launch, then larger projects tentatively announced in the following couple of years.
The problem is that the ones making the mess aren't going to pay for that, and I shudder at the costs involved in just space assembly of something the size of ELT...
Edit to the slow reply ;) - the 400 tons is just the estimate zerodur mirror segments for the main mirror, nothing of the support structures... and didn't include ~65 tons of spare segments (ELT plans to replace two daily or something like that).