https://wccftech.com/spacex-building-giant-tower-to-catch-230-feet-tall-rocket-during-landing/

SpaceX's first stage Starship spacecraft rendered as it enters the Martian atmosphere. Image: SpaceX

New details for Space Exploration Technologies Corp.'s (SpaceX) plans for the first-stage rocket booster of its Starship interplanetary launch vehicle system have come to light. SpaceX is currently testing the second stage of its net-generation rocket system in Boca Chica, Texas, as it builds the  Starship first stage, which will be responsible for propelling payloads beyond Earth's atmosphere.