JohnBrownsDream

If you might ever need to be reached at the number being shared there's always the route of VoIP products like Google Voice (free), or Twilio or MySudo (not free), where one can create virtual numbers for different use cases. In general it's more secure to share a VoIP number anyway since it isn't vulnerable to the same SIM swapping attacks that cell numbers are. I don't know that it's possible to create a Google Voice account without providing a real cell #. One could probably get around that with a burner phone.

Where there is only a short-term need for a reachable number for SMS verification or communication purposes there are services that provide temporary SMS numbers, like mobilesms.io. Because these numbers are recycled frequently, definitely don't use them to register anything important like a bank account or email address.

Fair point. It's still striking to me how much public money is being thrown at a project that will benefit just a handful of private citizens.

A quarter billion dollars to build just a prototype and retread the Concorde fiasco with all its attendant environmental destruction. What does this have to do with exploring space, which is what I thought was NASA's mission?